_ . E> RAR.Y OF THE UNIVERSITY Of ILLINOIS 590.5 FI v. 35 coo- 3 NATURAL HISTORY SURVEY 35 7 3 P- BIRDS OF THE PHILIPPINE ISLANDS SIQUIJOR, MOUNT MALINDANG, BOHOL, AND SAMAR AUSTIN L. RAND AND DIOSCORO S. RABOR FIELDIANA: ZOOLOGY VOLUME 35, NUMBER 7 Pu&Jisted by CHICAGO NATURAL HISTORY MUSEUM OCTOBER 26, 1960 BIRDS OF THE PHILIPPINE ISLANDS SIQUIJOR, MOUNT MALINDANG, BOHOL, AND SAMAR AUSTIN L. RAND Chief Curator, Department of Zoology AND DIOSCORO S. RABOR Field Associate, Department of Zoology Department of Biology, Silliman University FIELDIANA: ZOOLOGY VOLUME 35, NUMBER 7 Published by CHICAGO NATURAL HISTORY MUSEUM OCTOBER 26, 1960 Edited by LILLIAN A. Ross Library of Congress Catalog Card Number: 60-5S212 PRINTED IN THE UNITED STATES OF AMERICA BY CHICAGO NATURAL HISTORY MUSEUM PRESS Nat Hist f' : CONTENTS PAGE Introduction 225 Acknowledgments 225 Birds of Siquijor Island 228 Birds of Mount Malindang, western Mindanao 260 Birds of Bohol Island 310 Birds of Samar Island 363 Comments on special species 414 References. . . 440 223 Birds of Siquijor, Mount Malindang, Bohol, and Samar INTRODUCTION The 7100 Philippine Islands have been an interesting and attrac- tive field for the study of tropical birds for many ornithologists. As a result of their efforts, our knowledge of Philippine birds has gradu- ally grown with the years, although many problems in Philippine ornithology remain unanswered. Professor Dioscoro S. Rabor of the Biology Department of Silli- man University, in collaboration with Dr. Austin L. Rand of Chicago Natural History Museum and Dr. S. Dillon Ripley of the Peabody Museum of Natural History, has carried on, since 1947, studies of Philippine birds, and with the joint support, in terms of funds, equip- ment and supplies, of Chicago Natural History Museum, Peabody Museum of Natural History, and Silliman University, has explored numerous islands, especially in the highlands, which in the past were often inaccessible to collectors. The present paper sets forth the ornithological results of the explorations carried on by Rabor and his colleagues, assistants and students, on the islands of Siquijor, Bohol, Samar and Mindanao. New species keep cropping up in Philippine ornithology, even from islands or particular regions on certain islands, which have been supposedly thoroughly worked in the past; and there are still many regions in the Philippines that are virgin fields for the student and collector. ACKNOWLEDGMENTS The results set forth in this paper have been made possible only through the invaluable aid of many people, only a few of whom it is possible to mention below. We are grateful to Messrs. Ananias Kinilitan, Filomeno Empeso, and Domingo Empeso, Laboratory Assistants in the Biology Depart- ment of Silliman University, for their very efficient help as field collectors on these zoological explorations; without their untiring 225 226 FIELDIANA: ZOOLOGY, VOLUME 35 efforts, our bird lists for the various islands would not have been as extensive. We also thank many Silliman students, former students, and colleagues in the Biology Department, for their efficient aid in zoological explorations on various islands; among them are Messrs. Rodrigo Pepito, Avelino Torres, Rodolfo Gonzales, Jesus Sumangil, and Valfredo Rabor, all of whom, at one time or another, took charge of camps and collecting parties. We are grateful to Mrs. Lina Florendo-Rabor, who, on several occasions, was an important mem- ber of the expedition party and took charge of the camp activities other than those of collecting, thus allowing the collecting members of the party all the time to do their work. We also express our gratitude to various people on several islands, who gave us of their time and services, and even the use of their properties, to make possible the success of our work. Among them are Mr. William Anderson, Comp- troller of Silliman University, who, on two occasions, enabled Profes- sor Rabor to make preliminary surveys of various prospective collect- ing regions, with the use of his personal plane, which he himself flew. To the late Mr. Ismael Fortich and Mrs. Juliana Fortich of Sierra Bullones, we owe much for the help that they gave us when the collecting party was working in the interior of Bohol. To Mr. Lao Hian Beng and his family, of Catbalogan, the capital of Samar, we owe a great deal for the aid that they gave the party when we were in that town. By lending us their jeeps they made it possible for us to save most of our field equipment and supplies during the great 1957 fire that burned three-fourths of this capital town, includ- ing the entire business section. The Lao family helped us save our property during this unfortunate happening when the party had just arrived from Dumaguete City, Negros Oriental, and had stopped in Catbalogan temporarily, on the way to the interior of Samar. In the Mount Malindang work, on Mindanao, the officials of the Bureau of Forestry were extremely kind in supplying information and help to the field party. The District Forester's office in Dipolog attached Mr. Vincent Torres, the Forest Ranger in charge of the area, to the party, and our best thanks are due him and his office. We are indebted to Messrs. H. Deignan and T. Gilliard, and Dr. Charles Vaurie, and their respective institutions, the United States National Museum and the American Museum of Natural History, for the loan of comparative materials that were used in the present study. Professor Rabor expresses his great indebtedness to the John Simon Guggenheim Memorial Foundation, Chicago Natural History Museum, Yale University, and the United Board for Christian RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 227 Higher Education in Asia, for the research fellowships and travel grants that made it possible for him to come to the United States and work on the bird collections from various islands of the Philippines, at present in Chicago Natural History Museum and Peabody Mu- seum, with the advice of or in collaboration with Dr. Rand and Dr. Ripley. Birds of Siquijor Island Introduction and History of Collecting This is a study of a small, badly deforested central Philippine is- land, with special reference to the possible faunal effects of the small size of this island. Most of the studies on distribution of Philippine birds have approached the question from the viewpoint of classical zoogeography; relationships and proximity; changes in land masses; and faunal areas. However, a number of students in various parts of the world have pointed out ecological differences between faunas and populations of small islands and those of near-by larger land masses. These differ- ences appear to be correlated with small islands and can well be called "small island effects." The Philippines provide a wonderful field for such studies; no understanding of the avifauna can be reached without an evaluation of small island effects as well as the more usual zoogeographical aspects. We hope that the few observations recorded here will soon be augmented by others from other islands. The earliest collection of birds on Siquijor Island was made by the Steere Expedition to the Philippines in 1887-88, when the collecting party worked on this island in February, 1888. Thirty-seven bird forms were recorded, including three endemics: Loriculus pkilippensis siquijorensis, Hypsipetes s. siquijorensis and Dicaeum trigonostigma besti. F. S. Bourns and D. C. Worcester of the Menage Expedition to the Philippines (1890-93) next collected on Siquijor. They recorded 81 forms of which 44 were additions to the island's avifaunal list, in- cluding one more endemic, Zosterops everetti siquijorensis, the fourth on the island. This collection raised the total known bird forms on Siquijor to 87. Andres Celestino next collected on the island in September, 1907, and in April and May, 1908, for the Philippine Bureau of Science. He collected a total of 62 bird forms of which 9 were additions to the island's avifaunal list, making a total of 96 bird forms known from Siquijor as of 1907. 228 RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 229 Recently collections have been made on the island on several occasions by parties from Silliman University, headed by Professor Rabor and sponsored mainly by Chicago Natural History Museum. The island was visited in December, 1952, May-June, 1953, Decem- ber-January, 1953, and December, 1954. Dr. Rand was with the collecting party in December-January, 1953. Collecting was done chiefly at Lilo-an and Tag-ibo, in and near patches of forest, but col- lections were also made along the Po-o River (Lazi municipality) from near the coast up to Barrio Cangumantang in the interior, close to the center of the island. These most recent collecting activities yielded 67 bird forms collected and 5 sight records. Of the number collected, 13 forms have been added to the avifaunal list of the island 9 resident and 4 migrant. A new subspecies of the yellow-bellied thickhead, Pachycephala philippinensis siquijorensis, was described, representing a fifth endemic subspecies. After deleting several doubtful records such as Cuculus canorus and Cacomantis merulinus the Siquijor list stands as 107 forms (106 species plus 1 subspecies) ; of these 83 are Philippine forms and 24 are migrants. The list of migrants may be considerably extended by future work, but the list of resident species is probably fairly complete. The only separate paper on the birds of Siquijor is that of McGregor (1908, Notes on a collection of birds from Siquijor, Philip- pine Islands, Phil. Jour. Sci., 3: 275-281), based on the collection of Celestino, but a discussion of the island is contained in a number of papers, especially that of Worcester and Bourns (1898, Proc. U. S. Nat. Mus., 20: 551-566, 581), and the earlier Siquijor records were all incorporated into McGregor's A Manual of Philippine Birds (1909). Geography Siquijor is a small coral island, about 235 square kilometers in area, situated just within the entrance of an arm of the Sulu Sea. The island lies about 19 kilometers east of the nearest point on south- ern Negros, 25 kilometers southeast of Cebu, 30 kilometers southwest of Bohol, and 45 kilometers north of Zamboanga Peninsula of Mindanao. Siquijor is predominantly hilly and in many places the hills reach the sea, producing precipitous cliffs. At the center Mount Malabahoc (locally known as Bandila) reaches about 628 meters in elevation, the highest point on the island. Three marine terraces can be roughly traced especially in the vicinity of Tag-ibo on the southwestern part 230 FIELDIANA: ZOOLOGY, VOLUME 35 of the island, a barrio of San Juan municipality from the seacoast up into the central part. Siquijor is definitely coralline, and in the plowed fields fossils of the giant clam, Tridacna, are often encountered. On the hilltops there are numerous shells of molluscan species that are at present living in the seas around the island. Siquijor must have been formed quite recently, geologically speaking. Vegetation Siquijor is a common type of island in the Philippines: well cleared of forest and with a population too large to be supported by the island under the present system of farming, in which most of the people are engaged. However, a small manganese mine is operated in the central hilly part of the island. Recently there has been a steady migration of hill farmers to the government land settlement projects on the near-by islands of Negros and Mindanao. At the present time the greater part of the island, from coast to hilltop, is covered with cultivated fields, patches of second growth, and grasslands. The second growth patches, of various ages, repre- sent a stage in cultivation cultivated fields that have been left fallow to grow up to brush which will in time be cleared again while more cultivated fields will be left to grow up to brush for a time. The country of mixed grassland, second growth and cultivated areas, the parang type of vegetation, is especially common on the level places and on the bases of the hills. The soil is generally impoverished and in many places in the hills erosion has left only thin layers. In Tag-ibo and vicinity many hill- sides are bare rock. Streams are few and short, and most of them are dry for much of the year except after rains. These streams must have been better supplied with water when the island was covered with forest, as it probably was. Locally, pools persist in the Tag-ibo River near the wooded patches on its upper reaches. Second growth is well developed along the dry watercourses. Corn is the staple crop, although limited areas, mostly near the coast, are planted to lowland rice. The fields are terraced, to use water from the rainy season. In the hills camote (sweet potatoes), camoteng-cahoy (cassava), and a very little tobacco are planted. Coconuts are planted locally throughout. Carabaos, cattle, horses, and goats of the farmers graze on grasslands. Remnants of the original forest exist at only two places: Lilo-an, municipality of Maria, and Tag-ibo, municipality of San Juan; in both of these the forest has been much modified by cutting. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 231 At Lilo-an, close to the sea and about 50 meters above it (to the edge of the sea cliff), are about 400 hectares of forest. This is growing on what is presumably the newest marine terrace, which extends, with minor breaks, about 2 kilometers inland here. This forest is dwindling, as it is the source for local building material. Though the area is protected as a government reserve, cutting continues. Most of the taller, more valuable trees have been cut. Sometimes logs are dropped over the cliff into the water whence they are re- covered and transported by sea, making the task of the government guard very difficult. The other forest patch, in the hills of Tag-ibo about 5 kilometers from the coast, covers about 500 hectares on hillsides at about 300 meters altitude. As in the Lilo-an reserve, the better trees have been cut. Sawing places were found in well-hidden nooks in the hills just outside the reservation. Both of these patches of original forest belong to the modified dipterocarp-molave type of closed, evergreen forest. Originally there must have been extensive forest growth of one type or another, from the seacoast up to the mountain tops. From the remnants now, one can postulate that there probably were narrow strips of the mangrove type of forest in some places along the coast, and patches of the beach type of forest in places where the land slopes gently into the sea. The hills and the mountains, especially on their sides, must have been occupied by the molave type of forest, and in the rather level places and on the gentle slopes of the hills and mountains there must have been the modified dipterocarp-molave type of forest that did not quite become real dipterocarp forest. Compared with other islands the habitats on Siquijor are much like those on Bohol and on Samar, though on both of these larger is- lands there are more forest and more swamps and water, actually and probably proportionately. However, Cebu is perhaps poorer in hab- itats than Siquijor, and it is doubtful if any forest is now existing there. By comparison Negros and Mindanao are much richer and more varied. Besides second growth, cultivated fields, water and marsh there are still large areas of original dipterocarp forest in the lowlands and up the mountain slopes to an altitude of about 600-700 meters. Above that are mid-mountain forests that extend up to about 1700- 1900 meters, and above that is mossy forest, where the mountains rise higher. 232 FIELDIANA: ZOOLOGY, VOLUME 35 Zoogeography The division of the Philippines into faunal areas serves two pur- poses: it indicates areas whose faunas have had at least somewhat different histories, and it is a convenience in discussing distribution. Of course it has the merits (and demerits) of any classification, with difference of opinion as to how many categories to use in interpreting the varying patterns of different groups of animals. A certain degree of endemism in the birds occurs in many Philip- pine islands. Some of these can be grouped together when their birds are more closely related than are those of another group of is- lands. Inger (1954, Systematics and Zoogeography of Philippine Amphibia, pp. 468^471) would recognize only two faunal areas for amphibians: (1) the Balabac-Palawan-Calamian chain, and (2) the rest of the Philippine archipelago. Delacour and Mayr (1946, Birds of the Philippines, pp. 9-15) recognized three main faunal areas: (1) the Palawan group; (2) the eastern Philippine group, and (3) the central or Visayan provinces, with certain marginal areas Mindoro, Luzon Strait and Sulu Archipelago as districts. The latter classifi- cation we feel is a useful concept, though the units included in each area are not uniform. However, when we deal with an island such as Siquijor, with an impoverished fauna, its allocation is not clear. Siquijor as an island has probably had an independent existence since before the Pleistocene at least, for Pliocene limestone and Miocene limestone and shales are known. There is no evidence that the island has been connected with Negros or Cebu, though the 100- fathom line includes Siquijor with them. The depths between Siqui- jor and Bohol and Mindanao are in the neighborhood of 350 fathoms, indicating less possibility of land connections. Certainly no land connections were necessary to account for the avifauna of Siquijor. It would seem that Siquijor's avifauna could have colonized it from the surrounding islands, but prevailing winds could have been influential though the distances are short. The winds of the north- east monsoon prevail from December to May; those of the southwest monsoon from June to November. The typhoons in the Philippines usually originate over the Pacific Ocean east of the Ladrone Islands and pass over the Philippines in a west-northwest or west by north path. The course of the winds would favor a colonization of Siquijor from the west and northwest (i.e., the direction of Bohol). The following data apply to Siquijor. It has a small avifauna 82 resident species, as known. There are no endemic genera or species. There are five fairiy well-defined endemic subspecies: Loriculus RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 233 philippensis siquijorensis (extinct?), Hypsipetes s. siquijorensis, Pachycephala philippinensis siquijorensis, Dicaeum trigonostigma besti, and Zosterops everetti siquijorensis. The relationships of these Siquijor endemics point in various directions. Loriculus philippensis is a widespread species, with the Siquijor form most like the distant Mindoro form; Hypsipetes siqui- jorensis has only two other races, one on Cebu (a little known bird) and another on Romblon and Tablas, all of the Visayan group; Zosterops everetti ranges in the Philippines from Sulu and Mindanao north only to Samar and west only to Cebu and Siquijor (replaced on Negros by another species). Dicaeum trigonostigma is a widespread species, but the Siquijor race is closest to the Bohol-Samar-Mindanao race, not the Negros-Cebu forms. Pachycephala philippinensis is an eastern Philippine species, replaced on Negros by another species. The race P. p. siquijorensis is most closely related to the Samar- Bohol-Mindanao bird. The relationships of a few other, non-endemic subspecies are pertinent. The rail Rallus torquatus sanfordi, of Siquijor, is the same as that of Mindanao, not R. t. torquatus, of Negros, Bohol and north- ward. However, this allocation is based on longer bill size, possibly a small island effect not indicating real relationship. The Siquijor race of the owl Ninox philippensis is centralis, very similar to the Negros-Bohol bird and quite different from the Mindanao spilo- cephala. The Siquijor race of the brown fruit dove Phapitreron leucotis is albifrons, which also occurs on Samar, Leyte, and Bohol and is closest to the races on Luzon and Mindanao and quite different from the Negros subspecies. For the rest, the resident bird avifauna is of widespread Philippine species that give little guide to the origin or relationship of the fauna. The many strongly characteristic birds of Mindanao, Samar-Leyte- Bohol (eastern province) and Negros (Visayan province) are lacking. Presumably some may be lacking because of lack of suitable habitats (seep. 234). We can best conclude that Siquijor is a small island with an im- poverished fauna. Its avifauna probably came to it over seas and from various directions. The slight preponderance of eastern Philip- pine relationship (via Bohol) in the few pertinent data might cause one to include it in the eastern province. However, it probably should be considered a marginal island, between the eastern and central provinces. 234 FIELDIANA: ZOOLOGY, VOLUME 35 Ecological Aspects Zoogeography proper is not the only aspect of bird distribution to consider in studying the avifauna of a small island like that of Siquijor. While its avifauna undoubtedly was derived from that of the adjacent larger land masses and was influenced by ease of colo- nization from them, the ecology of a small island, probably in part an effect of its small size, also has something to do with the nature of its avifauna. Size of the Avifauna In general, small islands have smaller avifaunas than larger is- lands. That this is true of Siquijor is well shown by the following table: Area Breeding Birds sq. km. No. of species Siquijor 235 83 Bohol 3,973 138 Cebu 4,390 130 Negros 12,699 183 Mindanao 95,587 259 Distance from Larger Land Masses In general, the farther an island is from its "source of supply" the smaller its avifauna, but because of their geographical arrangement our islands cannot be compared in this respect. However, if we are correct in assuming that much of the colonization of Siquijor came from Bohol we should note that it is not the nearest island. The dis- tance from Siquijor to Negros is 19 kilometers; to Cebu, 25 kilo- meters; to Bohol, 30 kilometers; to Zamboanga Peninsula of Min- danao, 45 kilometers. Evidently factors other than distance affect colonization. In this case it seems to be prevailing winds (see p. 232). First Arrivals Excluding Other Colonists The manner in which quite distinct-looking but obviously related forms replace each other on island after island is a conspicuous fea- ture of Philippine avifauna. Steere (1894, Ibis, p. 420) was impressed with this phenomenon to the extent of putting forward the generaliza- that "no two species structurally adapted to the same conditions will occupy the same area." Of course Steere recognized only species, and many of his "species" are now considered subspecies. However, this idea has been elaborated since, especially in various publications by David Lack. It often appears now as follows: Two species of the RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 235 same genus can not occupy the same area unless their habitat require- ments are different. Otherwise they act as barriers to each other's spread. . There are two species reaching Siquijor which have representative species common on Negros: Pachycephala philippinensis (with P. plateni on Negros) and Zosterops everetti (with Z.nigrorum on Negros) . Both sets of species colonize small islands and occupy similar habi- tats elsewhere in the Philippines. It is possible that the early pres- ence of the eastern Philippine species on Siquijor, colonists from Bohol, has prevented the colonization of Siquijor by the Negros species. The bulbul Hypsipetes siquijorensis on Siquijor has habits very similar to those of the similar but somewhat smaller H. philippinus of Negros, etc. The similarity of the two species in life is striking. Their ranges do not overlap. Possibly the same mutually exclusive factor has kept H. philippinus, which has colonized many small is- lands, from colonizing Siquijor. It should be pointed out that a number of largely representative forms, such as Hypsipetes rufigularis and H. everetti, and Phapitreron amethystina and P. brunneiceps, once thought to be only well-marked subspecies, have since been found to live together on Mindanao and accordingly are definitely species. One species of each pair of birds, evolved in isolation, has been able to re-invade the range of its near- est relative. Difference in habitat may be found when the birds are studied. Occurrence of Two Species in a Genus There are some instances of two species in a genus living on the same island, but each with a different way of living; for example, the pigeons of the genus Treron. T. pompadora on Negros is a bird of the original forest, T. vernans of the second growth and cultivated land. On Siquijor both species live with considerable overlaps in habitat due to the degeneration of the forest habitat. Of the two rails, Rallus striatus and R. torquatus, the former prefers damper habitats, and of the two slaty rails, Amaurornis phoenicurus and A. olivacea, the same is true, the former favoring wetter places. The pittas, Pitta eryth- rogaster of the forest, and P. sordida of the second growth, present a similar case. The kingfishers of the genus Hakyon present on Siquijor a picture of three habitats, each occupied by a species: H. chloris lives along the seashore or in clearings and fields, often far from water; H. 236 FIELDIANA: ZOOLOGY, VOLUME 35 smyrnensis lives along streams and in open country near water; H. winchelli is a forest bird. A fourth, H. coromanda, is a winter visitor and lives in the forest, where it has an unusual diet of snails. However, there are a few pairs of species in which habitat differ- ences were not apparent: for example, the grassland mannikins in Lonchura (leucogaster and malacca). Birds of Higher Altitudes Living at Lower Ones on Small Islands This is a surprising but apparently a very real phenomenon in the Philippines. The fruit pigeon Ptilinopus merrilli is a mountain bird on the large island of Luzon, but it occurs unchanged on adjacent, small Polillo Island, where it lives at sea level; Columba vitiensis seems to be a high mountain bird in most of the Philippines but it lives at low altitudes on the small islands north of Luzon. The flycatcher Muscicapa hyperythra in general is a mountain bird but lives at low altitudes on Calayan. Pachycephala plateni has a similar type of distribution. In Zamboanga the brush cuckoo, Cacomantis variolosus, is a bird of the mountains, while below it lives another species, C. merulinus; on Siquijor only C. variolosus is known, living far below its normal range. The pigeon Columba vitiensis is a mountain bird in Negros and Mindanao; on Siquijor it occurs near sea level. To speculate, one could postulate that the range of mountain birds in the Philippines is really a series of small islands (in mountain habitats) surrounded by lowlands (of other habitats) and that it bears a similarity to small islands surrounded by the sea. Perhaps when C. variolosus occupied Siquijor it prevented C. merulinus from estab- lishing a foothold. This then would be another case of first arrivals one species excluding other colonists (see p. 234). However, the fruit pigeons of the genus Ducula present a different picture. Both the lowland forest Ducula aenea and the mountain forest D. carola occur. Species of Small Islands There are a number of species which have a very wide range from India to New Guinea but live only on small islands. Even the larger islands of the Philippines seem unsuitable as breeding places, though they may visit the coasts of some to feed. The nutmeg pigeon Ducula bicolor and the Nicobar pigeon Caloenas nicobarica are the most obvious Philippine examples of this. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 237 Though both have been taken on Siquijor, but only occasionally, they also are taken occasionally on larger islands. Evidently Siquijor is not small enough, or has no suitable habitat for them to be permanent residents. Another small island Philippine species is the gray imperial pigeon Ducula pickeringi that lives only on small islands off Borneo and Mindanao. It might have been expected on Siquijor but does not occur. Change of Habitat on Small Islands When a species lives on a small island it may live in a habitat somewhat different from that in which it ordinarily makes its home on larger land masses. In Siquijor the following such differences were noted (see p. 235) : Treron p. axillaris, Pitta erythrogaster , Columba viti- ensis, and Cacomantis variolosus lived in broken forest and near-by brush; on Negros the first two species lived in forest and the others were found in deep mountain forest. It is possible that the change from living in forest to living in broken forest and brushland has taken place in the last two or three hundred years, since the Filipinos have begun to raise corn and denude the island of forest. Absences of Certain Groups of Birds The non-occurrence of certain groups of birds on Siquijor is very noticeable. There are no records of such forest birds as hornbills (Bucerotidae), barbet (Capitonidae), woodpeckers (Picidae), titmice (Paridae), nuthatch (Sittidae), or drongo (Dicruridae). All of these might be expected in the small patches of forest that are left on Siquijor, as all are found on Negros and on Mindanao. Perhaps some or all of them did occur formerly and have disappeared as the forest decreased in size. Perhaps they never inhabited the island. However, there are certain grassland species that might be ex- pected to occur but have never been found, for example, the button quail (Turnix) and the lark (Mirafra). While the first is often scarce and difficult to find, the second is common and conspicuous on many islands but seems to be actually absent from Siquijor. Perhaps the two genera may yet colonize it, for the extensive grasslands are probably in the order of 200 years old only. Patterns of Variation Ordinarily, within a genus, similarity in color, pattern, and meas- urements is taken to indicate relationships. This is probably usually 238 FIELDIANA: ZOOLOGY, VOLUME 35 true, but there are indications that it may not always be so. Par- ticularly within a species, characters may repeat themselves in widely separated parts of the range. LARGE BILL OF ISLAND FORMS: This is a common phenomenon in many parts of the world. Why it should be, we don't know. In Siquijor only one of the endemic races, that of Pachycephala philip- pinensis, is characterized by a large bill, though the local population of NiUava rufigastra tends also to have a larger bill a difference of less than subspecific value. The Siquijor specimens of Rallus torquatus have long bills, like R. t. sanfordi of Mindanao. Hence they are referred to that race, though the longer bill may have arisen independently as a small is- land effect. OTHER CHARACTERS: The main characters shown by the other Siquijor endemics seem to point in no special direction : less yellow in upper parts (Loriculus) ; darker, blacker-headed (Hypsipetes) ; grayer, less yellow throat (Dicaeum) ; paler (Zosterops) . It is interesting to point out, however, that the endemic race of flower-pecker (Dicaeum) is more unlike the Negros form (the nearest geographically) than is the Bohol-Mindanao bird, which is somewhat intermediate in color between the other two despite the range. The endemic race of hanging parakeet (lacking yellow on the hind crown) is more like the Mindoro race than it is like its nearest neighbors. On Siquijor there occur two other species whose populations would be recognizable as subspecies if they were compared only with their nearest neighboring populations: Kakatoe haematuropygia and Tanygnathus lucionensis. However, elsewhere in the Philippines, on more distant islands, the characters of the Siquijor populations re- appear. The geographical pattern given by characters is thus a checkerboard one, and the usefulness of naming subspecies that can be recognized only by geography seems doubtful. In another Siquijor species, Oriolus chinensis, what seems to be a small island effect is not apparent. The species shows an increase in size in Fuga and Calayan islands, in Busuanga and Cuyo islands, and in the Sulu islands. Each population seems to have acquired larger size independently. Variation in other characters permits recogni- tion of two races (see Rand, 1951, Fieldiana, Zool., 31: 591), and in these characters the Siquijor Oriolus fit into the general pattern that RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 239 seems to represent a north-south cline in being less yellow to the south. Migrants The list of migrants known from Siquijor is small, and all of them come from Asia. They are: Gorsachius goisagi, Butastur indicus, Squatorola squatorola, Pluvialis dominica fulva, Charadrius alexandri- nus dealbatus, C. leschenaultii, Numenius phaeopus variegatus, Tringa totanus eurhinus, T. glareola, Actitis hypoleucos, Heteroscelus brevipes, Arenaria i. interpres, Gallinago megala, Clamator coromandus, Cuculus saturatus horsfieldi, Ninox scutulata japonica, Halcyon coromanda bangsi, Hirundo rustica gutturalis, Motacilla cinerea melanope, Anthus gustavi, Lanius cristatus lucionensis, Monticola solitaria philippensis, Phylloscopus b. borealis, and Muscicapa griseisticta. Probably this list could be much lengthened, especially in regard to migrant shore birds. An interesting point arises in regard to several species that occur. Several migrants from Asia were found more commonly on Siquijor than would be expected, judging by Rabor's experience on other is- lands. Four specimens of Gorsachius goisagi were taken in the limited work on Siquijor, compared with only two other specimens in the Chicago Museum collection from all the other Philippine field work. Even more striking is the case of Halcyon coromanda bangsi, of which we have eight specimens from Siquijor, taken in two months. It is otherwise known only from two Negros specimens taken by Rabor recently. The other race, major, has been recorded from many stations. Can this indicate that certain species or subspecies have restricted winter ranges in the Philippines? Post-Breeding, Wandering Sea Birds Sea birds are not common in most of the Philippines, though big colonies of terns, boobies, and frigate birds do nest in the islets in the Sulu Sea or north of Luzon. The only such species listed as visitors to Siquijor are the terns, Thalasseus bergii and Sterna fuscata. LIST OF SPECIES The specimens in the following list are in Chicago Natural History Museum except those labeled S.U., which are in the Silliman Uni- versity collection. 240 FIELDIANA: ZOOLOGY, VOLUME 35 The habitat preferences are based not only on Rabor's Siquijor work, but on a composite of his experience with the species on various islands. The data on previous collections have been taken from McGregor (1909, Manual of Philippine Birds) and are listed first, in parentheses, followed by Rabor's observations and a list of specimens collected by him. It seems unnecessary to give the precise locality and date for the individual specimens unless for some special reason. Hence they are recorded in condensed form. In a few cases, more discussion of a species is pertinent than was advisable to insert in the list of species. This material has been assembled into a separate section at the end of the report, and the relevant species are marked with asterisks indicating such additional data. The list of 106 species and 1 subspecies recorded for Siquijor is as follows: Family ARDEIDAE Egretta garzetta garzetta (Linn.) (Coll.: Bourns and Worcester). Habitat: in marshes or along shallow rivers, and on tide flats. Demigretta sacra sacra (Gm.) (Coll.: Bourns and Worcester). Habitat: along exposed, rocky beaches. Bubulcus ibis coromandus (Boddaert) (Coll.: Celestino). Rabor: 1 '*' ( norther ?P eak ) '/ Mt. 'Dapiak \ ,,^ "' Mf Malindof ^ / '"-""' y // / ./> Salog Peak? / : /' \ (main peak) Clarin i V yV /' Map Showing Routes of Expeditions of Major Mearns and Chicago Natural History Museum. 263 264 FIELDI ANA: ZOOLOGY, VOLUME 35 plenty of running water we went into camp. At 8:00 A.M., May 10, we broke camp, and after following the trail for about 2> miles more we crossed the Magguiaguay River near Tangob and arrived at the President's house at 10 A.M. There 8 cara- baos were secured to carry the largest portion of the rations, which had arrived by boat from Misamis, and after engaging a new guide the party left at noon for Catagan, passing through Tangob, which is a town of about 3000 inhabitants, mostly Filipinos, and followed a trail much used by Subanos, which was mostly northwest for 4 miles. The ground is almost level, rising hardly noticeably to an elevation of 200 feet. On both sides of the trail are large clearings covered with grass, and up to this point, which is actually the foot of the Malindang group, travelling is very easy. Here we crossed the Malabug River, which at this point is about 50 feet wide and has running water. About one mile east of this point, the water of the Malabug River disappears between the rocks underground. From here the trail is rocky, over rolling ground and through dry ravines, timber, and underbrush on both sides. Just before reaching Catagan we passed through a large hemp grove. At 3 P.M. our party reached Catagan, a small Subano settle- ment, altitude 1100 feet. The casas are built on the slope of the mountain and surrounded by hemp groves. The largest casa in the settlement, about 100X40 feet, belongs to Datto Anib, the chief of the settlement. This Subano tribe, and especially the Datto, an old man, did everything in their power to make it com- fortable for the party; the Datto even moved his family into another shack and gave us possession of his own casa. Later on, he provided the party with rice, chickens and eggs, which were very cheap. The religion of this tribe is sun wor- ship; and one of their customs is to vacate a casa after its master has died, which accounted for several empty shacks which we found in the neighborhood. On May 15, Major Mearns, Captain Jervey, and Lieutenant Earle made a reconnaissance north of Catagan and reached the peak of Mount Lebo, elevation 5750 feet. This is the mountain which Captain C. C. Smith ascended in 1904. On the same day, Major Mearns, descending west of Mount Lebo, found a narrow ridge leading west; this the party followed the next morning for about two miles and came to the foot of another mountain which they ascended. This peak has the same elevation as Mount Lebo (5750 feet); barometer readings one hour apart. This very prominent conical peak was named Mount Bliss. From it a very good view is offered of Grand Malindang Peak; but as a canyon 2500 feet deep made any further progress impossible, after taking readings on the different mountain peaks and sizing up the general locality, Mearns camped on Mount Bliss, returning to Catagan May 17, 1906. On May 18, 1906, Privates West and Mott left Catagan for the purpose of find- ing a passage through the canyon north of Mount Lebo. They ascended this moun- tain, and after camping there they descended the northern slope of Mount Lebo on May 19; after a perilous climb down the canyon about 2500 feet, they arrived at an unknown river which came from the northwest. This river they followed for about two miles east, and on finding it not passable for cargadores they camped there. On May 20, West and Mott followed the river to its source and found it leading up to a high divide between Mount Bliss and Mount Bentad. Here they ascended Mount Bliss over the divide, which they found comparatively easy, and having thus successfully explored the gorge, and found plenty of water, they re- turned to Catagan, May 22, 1906. On the advice of Datto Anib, Lieutenant Wood, with a detachment of con- stabulary, started May 18 for the Moro town of Balinsang to find a guide for RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 265 Grand Malindang, but found none. He then explored several rivers entering into Misamis Bay, but found all impracticable for cargadores with the exception of the Malabug. This river Lieutenant Wood followed north on May 20. At the eleva- tion of 2400 feet he came to a Subano settlement of 4 or 5 casas, but the inhabitants knew of no trail to Grand Malindang. From here he followed the river to 3000 feet elevation, where a small tributary came from the north into the Malabug. From here Lieutenant Wood climbed to the peak of Mount Lebo to take observations, as it was almost impossible to determine the locality from the gorge of the Malabug. On May 21 he again descended to the river and followed it up to an elevation of 3350 feet, where it divided, one branch going north, the other northwest. He fol- lowed the larger one to an elevation of 3810 feet and found it impossible to go further, on account of the roughness of the country. So he decided to ascend Mount Bliss, which he found to be very difficult. Here he camped, returning to Catagan, May 22, 1906. On May 23, Hutchinson and Private West started out to find a way of getting to the summit of Grand Malindang by following the lower course of the Bliss River (so we named the river which West and Mott discovered). A Subano guide led them northeast from Catagan through the Subano settlements Binot and Kapata- gan across several rivers (which are located on the new map). No trail leading any further north, they followed through the forest, going mostly 20 west of north. This course they kept for nearly 3 hours, when the rim of the gorge was reached; elevation 3200 feet. A thousand feet below, they beheld the Bliss River, impossible to reach, as the slopes were almost perpendicular. The party camped here, and on the next day tried in vain to find a way to go down to the river; so they followed the gorge for some distance south and then by a compass route returned until they struck the Naculan Trail, where they camped, returning the next day by way of Binat to Catagan, arriving May 25, 1906. On May 19 Captain Jervey and Lieutenant Earle, with Privates Bentley, Cragan and Egbert, returned to Misamis, and here Captain Jervey engaged a guide for Jimenez, a town northeast of Misamis, to inquire about a trail, which, the Subanos said, led from that town to the foothills of Grand Malindang. But on arriving at Jimenez, Captain Jervey and Lieutenant Earle received telegraphic instructions from Department Headquarters to return to Zamboanga. Before leaving Misamis, Lieutenant Earle and Private Bentley laid off a base line on the beach and took readings by transit for triangulation on the peak of Grand Malindang. Captain Jervey and party returned then by vinla to Camp Overton, leaving Misamis May 22. On May 25, Lieutenant Wood had been ordered to Iligan, and he left Catagan the same day. The party having thus been reduced to almost one half of its original strength, Major Mearns decided to reach Grand Malindang by crossing the Great Gorge north of Mount Bliss. Therefore, on May 26, the party started from Catagan at 8:15 A.M. and followed a trail mostly 340, with high grass on both sides for about a mile, then woods and underbrush. Finally we struck the Balinsang Trail; this we followed for some distance, and then found the bed of a dry river; after follow- ing this for some time we crossed another small ridge and struck the bed of the Malabug River. This we followed for 300 yards. The river is about 60 feet wide, but the amount of water would not make more than a 6-inch stream. After leaving the river, we followed the long ridge, which led at an almost continuous slope of from 15-20 for 8 miles, to the top of Mount Lebo. It was here fairly good travel- 266 FIELDIANA: ZOOLOGY, VOLUME 35 ling, as underbrush was not very dense but there was more high timber, with trees from 100-200 feet tall and from 2-5 feet in diameter. At 2:15 P.M. we reached Mount Lebo, and from here followed over a narrow ridge about 20 feet wide, for two miles west until we reached the foot of the peak of Mount Bliss, reaching its summit at 3:45 P.M. May 26. Here the party went into camp, and as the vegetation was very bountiful and mountain birds abundant, Major Mearns decided to stay there for several days. On May 28 Private Daniel W. West, with Sergeant Pasandalan, constabulary, and 4 cargadores, started to reconnoiter the gorge and if possible to find a trail to the summit of Grand Malindang. He went down to the Bliss River, north of Mount Bliss, and after following it for several miles, ascended the ridge to the north, sup- posing that it was a foothill of Grand Malindang. He followed this ridge until he got to a peak from where he could get some bearings, and found that Grand Malindang was almost due north. Therefore he continued along the ridge, climb- ing higher and higher until he reached the very peak on May 29; there he found to his disappointment that he had climbed the wrong peak, although it was only about 800 feet lower than Grand Malindang, and that mountain was only a mile away. Seeing that he could not reach this one peak, which had become the mecca of our hopes by this time, as there was a gorge about 5000 feet deep separating the two mountains, and not being able to continue any further, West and Pasandalan camped that night on top. Sergeant Pasandalan shot a deer which replenished their stores somewhat and turned out, later on, to be a new species of its kind, as West saved the skin and skull and brought them back to camp. The next day, the party started on the return trip and descended the mountain to the left; at an ele- vation of 5000 feet they found several springs, and they followed the small creek which led from one of them. As it was the easiest way of travel they kept follow- ing the river it entered into for about 6 miles, when, at a lucky moment, they got a view of Mount Bliss; following then the compass, they climbed over a ridge and reached the Bliss River and hence returned to the camp on Mount Bliss in the afternoon, May 31. On June 1 the main party started from Mount Bliss and followed over a hog- back down the north slope to the ridge which connects Mount Bentad partly with Mount Bliss. This ridge we followed until the water was plainly heard from below, and here we descended to the Bliss River. This river we followed for about 2 miles. It was from 50 to 70 feet wide, with water enough to make a 10-inch stream. The grandeur of the foliage on the banks of this river was very striking. Palms, ferns and vines constituted the undergrowth, while mighty narra and numerous soft wood trees rose to a height of more than 100 feet. At a point blazed by West on his expedition, the party turned to the north and from 3200 feet elevation at the Bliss River we climbed to the peak of this ridge at an elevation of 4900 feet. From here, instead of following the ridge as West had done, we descended on the north side, which was very steep, and at an elevation of 3800 feet, struck the Malin- dang River at 6:15 P.M. There we camped and became very closely acquainted with quite a few land leeches, which inhabited this river gorge as thickly as mos- quitoes at Zamboanga. These leeches are so peculiarly constructed as to be able to grow, at your expense, to about % inch in diameter, without being discovered. At 8:40 A.M. June 2, we started to ascend the Malindang River. It was from 50 to 60 feet wide, and contained from 6 inches to 2 feet of water. The river-bed was continually rising at a 5-8 incline. The water came down in continual rapids. The scenery of this river was very beautiful, especially in some places where the RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 267 river came through narrow canyons with perpendicular rock walls on both sides, from 100-200 feet high, covered with moss of varied descriptions and flowers wher- ever your eyes might turn. In some places, mighty trees, growing on opposite sides of the river, joined their branches, and vines and orchids, which were everywhere, completed the most gorgeous of arches. From the right, as also from the left, several small tributaries entered the Malindang River, over falls from 40 to 60 feet high. Thus we continued for about 6 miles, when, at 1:45 P.M., we reached the place where the Malindang River branched into two forks, one coming from the north, the other from the west. We followed the one from the north, the smaller of the two, and named it Raspberry Creek because we had to chop our way with bolos through a mass of raspberry bushes, which grew on both sides of the creek and had joined hands across it. We climbed over several falls. Here, also, we found species of violets the same as in the United States growing on the banks of the creek from 20 to 30 feet high, and then came to one about 50 feet high which we could not reach. Here we branched off to the right and climbed up to a main ridge. We found, at 6100 feet, a level spot, and went into camp at 3:15 P.M., June 2; we named it McMurray Flats after Jackson C. McMurray, Hospital Corps, U.S.A. The next morning we got a fine view of Malindang Peak from a high tree at McMurray Flats, and as the rest of the climb looked favorable, decided to start for the peak the next day. At 9 A.M., June 4, Major Mearns, W. C. Hutchinson and myself started for the top. We followed a narrow ridge at an angle from 40 to 50, first going north- west and then north. It proved to be the hardest climb of the whole expedition, as, in many places, we had to climb hand over hand almost straight up. The last 1 500 feet from the summit was covered by a heavy tundra. Moss covered every- thing, in some places a foot and more thick; and branches 2 inches in diameter, looking like the trunk of a tree, or immense roots, made climbing dangerous. Among these moss-covered branches grew the most beautiful white and red orchids and many other kinds of small white, yellow and blue flowers. In some places on the side of the mountain and on the ridge were large patches of cogon grass. At 11:30 A.M. we reached the peak of Grand Malindang; but it was so foggy that we couldn't see 50 yards anywhere; but as the ridge did not lead any further, we concluded that we had reached our goal. Mr. Hutchinson, in scouting around on top, discovered a small spring not more than 100 yards from the peak; and by digging a hole as a reservoir, we were pro- vided with ice-water, as the temperature never went above 58 and not below 50, air temperature. We next proceeded to build a big fire, as it was bitter cold and damp from the thick fog, and established the camp. Major Mearns returned to McMurray Flats that day, for the purpose of bringing up more provisions and mammal traps. Mr. Hutchinson and myself stayed on top to take observations, when the atmosphere should become clear. The clouds disappeared about 4 :00 P.M. and the atmosphere became very clear. We climbed a large tree, which had fallen partly over the edge of the peak and gave us therefrom a view to all sides, a view too grand for description. Down before our eyes lay Mindanao, like one great miniature, mountains 3000 feet high looking like small hills, and beyond them, from the coast, very clearly defined, stretched the ocean in its calm magnificence to the very horizon, many hundred miles away. I took readings on all the prom- inent points, compass, and clinometer. After supper, we watched for sunset; it came later than usual. The atmosphere was as clear as crystal; only a few clouds 268 FIELDIANA: ZOOLOGY, VOLUME 35 were floating far beneath. The sight alone was worth the climbing of grand old Malindang. The following day Major Mearns returned. Privates Mott and McMurray and Senor Estrellas also climbed to the top that day, but returned in the afternoon. That day we erected on top a stone monument 3 feet high; and on top, in the monument, was put a bottle with the itinerary of the expedition. Major Mearns stayed on the summit for 3 days, and collected a good many birds, animals, and botanical specimens. June 7 we descended to McMurray Flats. On June 8 the whole party returned to the camp on Mount Bliss, and June 9 marched from there to Catagan, where we rested for one day. June 11 we bade farewell to our friend Datto Anib, who had so hospitably received and entertained us, and went down to Tangob. From there we returned to Misamis by vinta, arriving at 4:00 P.M., June 11. Field Work, 1956, by D. S. Rabor The aerial survey that Rabor conducted in March, thanks to Mr. Anderson, showed that the lower slopes of Mount Malindang had been extensively deforested, especially on the south and southeastern sides of the mountain, where the slopes are cleared and planted, with well-marked trails, up to 4000-4500 feet. Thus the difficult foothills that Mearns found forested and which caused him so much trouble in finding a way up this approach from the southeast, would now be comparatively easy to cross. However, two aspects of the west and northwest slopes of Mount Malindang led Rabor to select that approach. First, the greatest extent of virgin forest was there, the original forest having been cleared up to only about 2700 feet (in 1956) . Thus the fauna of this lower forest belt, already gone, with the forests, from the southeast- ern face, could be investigated. Secondly, a national road, under construction for the last five years, now extended from the town of New Pinan to the northwestern base of Mount Malindang and made this route practical. Ten years ago, where this road now runs was un- broken virgin forest, and this approach would have been impractical. The Expedition party of fifteen members, headed by Rabor, in- cluded an Instructor of the Biology Department, Rodolfo Gonzales, as Assistant Head of the party, and students and assistants of the Biology Department of Silliman University. The party left Dumaguete City, Negros Oriental, March 25, 1956, by boat and arrived at Pulawan Port, Zamboanga del Norte, the same day. A specially chartered truck took the party and equip- ment to the Office of the District Forester of the Bureau of Forestry, at Dipolog, to secure information on the area in which to collect. As a guide for the party the District Forester's Office assigned Mr. Vincent Torres, the Forest Ranger in charge of the Mount Malin- RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 269 dang area that fell under the jurisdiction of Zamboanga del Norte. Mr. Torres became a very important member of the Expedition party from then on. The truck brought the party to Salvacion that same night. On March 26, the party proceeded to Barrio Buena-Suerte, which is about 9 kilometers from Salvacion, and from which Mount Malin- dang can be seen in the distance. The main part of the load now was taken in carts and on carabao-back, and the personal packs were car- ried on the backs of the members of the party, who went on foot. The national road was passable by truck only to Salvacion, and from the latter to Buena-Suerte; here it was being constructed, and was not yet fit for use by heavy vehicles. On March 27 the party proceeded to Sitio Gumay, 2700 feet alti- tude and about 6 kilometers from Buena-Suerte, at the very edge of the forest of Mount Malindang. Below Gumay the countryside was well cleared and planted to corn or sweet potatoes, or left to tall grasses, cogon (Imperata cylindrica) and talahib (Saccharum spon- taneum) . The country was rolling and the climb proceeded gradually upward from hill to hill. The load was now carried on the backs of carabaos and people. A camp was set up in Gumay where the equip- ment and supplies, which could not be transferred in one trip from Buena-Suerte, were temporarily stored. An advance party of five expedition members and five porters, went ahead and established the main camp at Sitio Masawan, about 4300 feet elevation, in a small abandoned clearing not far from the Dapitan River gorge, and on its western side. The gorge at this point was easily more than 1500 feet deep and sheer in most places. A small house in an abandoned clear- ing in dense forest was repaired and was used as sleeping quarters by some members of the party. It took several days to transfer all the loads to Masawan from Gumay, a distance of about 18 kilometers. It was mostly a grad- ual climb, but two abandoned clearings were filled with the fallen tree trunks and dense second growth. Here we had to walk on the fallen crisscrossed tree trunks. On March 30 the party and all the load finally reached Masawan. Collecting activities began this day, and continued until April 14. Collecting covered Masawan and sur- rounding localities for about 10 kilometers around, both on the west- ern and eastern sides of the Dapitan River gorge, including Penacio, Canon, and Bulongkot. On April 14, the main party established a sub-camp at Gandawan, 4500 feet elevation, about 8 up-and-down kilometers from Masawan 270 FIELDIANA: ZOOLOGY, VOLUME 35 and still farther southeast in the direction of the main peak. Two people were left in the Masawan camp to take care of the equipment and supplies and to continue collecting. The camp at Gandawan was a small Subano hut, one of three in a beautiful valley surrounded by towering mountains with elevations from 5500 to 6200 feet. Here the Subanos grew their sweet potatoes. This valley contained about 200 hectares of plain and gradually slop- ing land but at the time only about 10 hectares were cultivated and the Subanos lived permanently in Canon, a barrio near Buena-Suerte, in cleared areas, at the base of Mount Malindang. They came peri- odically to plant, clean their fields, and harvest their sweet potatoes. There was a family of five who lived in the valley most of the time, because the father was mainly a hunter and he depended more on the wild game that he got with the aid of his dogs than on the sweet potato crop that his wife and children looked after mostly. All around this valley was virgin forest except close to the cultivated areas where new clearings were being made; here the fallen giant for- est trees, many freshly cut, were still on the ground. Sitio Gandawan was at the boundary between Zamboanga del Norte and Misamis Occidental Provinces, but it belonged to the former. Collections were carried on in Gandawan and the surrounding localities for about 5 kilometers radius, including Sitios Bulongkot and Napangan. Both the eastern and western sides of the Dapitan River gorge were collected in. On April 20, the party divided. One half stayed in Gandawan to continue the work there, and the other half proceeded towards the main peak, the source of the headwaters of the Dapitan River. A sub-camp was established in a small valley that nestled among very high peaks; one of them, the highest, toward the east, was one of the two main peaks of Mount Malindang, the northern peak or Dapitan Peak, 7450 feet in elevation. The camp, about 5100 feet in elevation, was right at the base of the abrupt climb toward the north- ern peak. At this point, the Dapitan River was a small, shallow mountain brook about 4 feet across, with its bank about 4 feet above the water surface. About 200 meters farther up, the same river be- came a smaller and shallower brook, about 3 feet wide and with banks hardly a foot above the water surface. The gorge of the river was about 2 kilometers below our camp site. Here the river, still small, descended close to 1000 feet and here the gorge began and extended down to the very base of the Mount Malindang moun- tain range. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 271 The distance between the northern peak and our sub-camp at 5100 feet was too great for effective collecting, so a small camp was made on the ridge of the main slope toward the summit of the north- ern peak, at an elevation of about 6500 feet. Water had to be carried up, in a five-gallon can, from the Dapitan River headwaters, about 1400 feet below. From this small camp, it took about 2% hours of difficult climbing to reach the flat top of the northern peak. From the summit we could see a canyon, easily about 2500 feet deep, that separated the lower northern peak from the much higher southern one, locally known as Salog Peak, where the south-flowing Salog River begins. From April 20 to May 5, collections were made in Dapitan River headwaters localities, including the areas around Lake Duminagat, a mountain lake about 8 hectares in area, nestling among high peaks. (Incidentally, this mountain lake is not on maps of the Mount Mal- indang localities and is not known except by Subano hunters.) On May 5, in the afternoon, this party broke camp and went back to rejoin the others in Gandawan. On May 6, the whole party went back to the main camp in Masa- wan. Here collections were made in the surrounding localities of Penacio and Canon, and in the areas between Gumay and Masawan, about 3500 feet in elevation. On May 10 the party came down to Gumay and established camp. Collections were carried on from Gumay up to about 3500 feet ele- vation, in the original forest areas, in the localities that were hardly touched from the Masawan camp, and below, in the cleared areas down to about 2000 feet, for a radius of about 5 kilometers. On May 18 the party left Gumay for Buena-Suerte, where we stayed overnight. On May 19 we proceeded on foot, the loads in carabao carts, to Salvacion, where a specially chartered truck took both loads and men to Dipolog, then to Pulawan Port to wait for the steamer. The steamer was delayed one day, so it was not until May 20 that we left Pulawan Port for Dumaguete City. The rains were almost continuous throughout the entire stay of the Expedition party in the high Mount Malindang localities, except for four days when the sun stayed bright from early morning to sun- set; even then it rained at night. At lower altitudes during the last few days of March up to about April 15, the sun was always bright from early morning until about 1 or 2 o'clock; then rain clouds would develop, soon followed by strong rain for about 2 hours. Immediately before sunset, the rain 272 FIELDIANA: ZOOLOGY, VOLUME 35 would stop and the sun would shine again through a cloudless sky. From about April 15 until April 30, the sun would shine from early morning until about 11 o'clock; then heavy dark clouds would de- velop, soon followed by rain until about 4 o'clock. The sunset was most often sunshiny but only for a short time. Usually there was no rain during the night until about 3 or 4 o'clock, at dawn, when the showers, from light to heavy to a real rain, would start. Usually they ended about 6 o'clock, and the sun would come up bright. From about May 1 to May 10, the sun as usual would come up bright and stay so for about 1 or 2 hours; then dark clouds would develop and rain would soon follow, continuing until about 4 o'clock. Again, there was often no rain until dawn. From about May 10 until May 17, when we had to go down to Buena-Suerte, there was already almost continuous rain not very hard, but continuous that made collecting very difficult. From May 10 until May 18, when the party was working in Gumay, we could see that there was still continuous sunshine in the lowlands in distant Dipolog and New Pifian. In fact, when we were forced to wait for the steamer in Pulawan Port, we passed a very hot day at the wharf. People in the lowlands told me that the rains would begin about the end of June in the lowlands, but that Mount Malindang would always be covered with dense mists as early as May. Description of Collecting Localities 1. Buena-Suerte (2000-2700 feet elevation). A well-settled bar- rio of Christians and Subanos, in rolling country (actually the foot- hills of Malindang), with numerous cultivated farms and houses. The houses were mainly located along the route of the prospective national road. There was no more original forest within 4 or 5 kilom- eters of it. At the time that we were there, the newly constructed national road stopped about 3 kilometers from the barrio proper, in the direction of the west coast, but a very well-developed trail for both men and carabao carts led to it. Many clearings were left to tall grass, and here and there were dense patches of second growth- clearings that had been neglected during the last five years or so. 2. Gumay (2700-3000 feet elevation). A very tiny sitio with about five Subano houses that formed a cluster on top of a well- cultivated hill, close to the edge of the original forest of Malindang. Gumay was about 5 or 6 kilometers from Buena-Suerte. Like the latter, it was already well cleared and cultivated on the side toward the lowlands, but with virgin forest toward the mountain of Malindang. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 273 The forest in this area, up to about 3500 feet, was dipterocarp rain forest type, with the typical three-storied character of the trees very well shown. There were extensive patches of dense second growth immediately adjoining the forest edge. 3. Penacio (3000-3500 feet elevation) . This was the largest bar- rio of the Subanos that we saw. The main group of houses was at the very edge of the forest, with some houses scattered in the cleared areas below, which were mostly planted to crops of corn and sweet potatoes. Interspersed among the untouched forest there were also patches of cleared areas which undoubtedly were new clearings that had only been planted once or twice, because the half-burned trunks were still in evidence. In addition, there were newly cleared areas with the felled trees still unburned, for they were not dry enough to burn. Then there were patches deep inside the dipterocarp forest and rather far up the slope, where the underbrush was already being cut so that the forest was very clean below. This was in preparation for the cutting of the taller growth, including the giant, dominant dipterocarp trees. Some of the hills near the group of houses were covered with tall grass and patches of second growth very difficult to penetrate. 4. Masawan (3500-4500 feet elevation). On the way to Masa- wan from Gumay, the trail passed through unbroken dipterocarp rain forest, up to about 3500 feet elevation (after about 10 kilometers gradual climb), beyond which the three-storied character of the tree growth began to be indistinct. Also, this was the beginning of the appearance of the Manila copal tree (Agathis alba} which the Subanos called Dingan. The forest was what might be called a transition type between real dipterocarp rain forest and real mid- mountain forest. Nearer Masawan, we traversed two clearings, each about four or five hectares in area. Apparently, these clearings had never been planted, because the felled giant trees, lying in all directions, had not been burned. The main camp was located in a small abandoned clearing and here again many large trees were still standing while the lower tree growths had already been cut down. The camp site was surrounded with transition dipterocarp-mid-mountain type of forest. The terrain was very rough, as at lower elevations, with numerous draws, deep creeks, and steep mountain sides, all densely covered with original forest. 5. Gandawan (4500-5500 feet elevation). The way to Ganda- wan from Masawan was very rough; for the greater part the trail 274 FIELDIANA: ZOOLOGY, VOLUME 35 passed under virgin forest of the transition type, except for a small abandoned clearing on top of the ridge of the main elevation (6000 feet) that we had to cross before going down rather abruptly to the valley where Gandawan was located. Gandawan itself, just a small cleared place surrounded by forest, was on level land and on land that gradually sloped upward to the surrounding mountains. The Dapitan River gorge, on the northeast of the clearing, was no longer very deep at this point. The forests in the valley and up the lower parts of the mountain slopes were transition dipterocarp-mid-mountain type, but about half way up the mountains and on the ridges the forest was mid-mountain type, with the characteristic two-storied tree growth and no very tall trees. Also, a luxuriant growth of epiphytes and mosses began to appear on the trunks and branches of the trees. 6. Napangan (5500-6200 feet elevation). The trail leading to Salog Peak, the main peak of Mount Malindang, passed through this place. This was along the chain of peaks that started from Masawan and connected with one another by ridges that dipped into shallow draws between peaks. The forest was typical mid-mountain type. 7. Bulongkot (5500-6500 feet elevation). We crossed the Dapi- tan River gorge and exactly opposite Napangan was Bulongkot. The area was very rough and the peaks were all covered with mid- mountain forest. 8. Dapitan River headwaters (5100-7450 feet elevation). The whole area from 5100 up to about 6500 feet was covered with mid- mountain forest. From 6500 feet up to the top of the peak, the ridge and the steep sides were all covered with mossy forest. The trail sometimes passed over very crooked trunks of trees that had inclined or had been blown down by the strong winds and which connected with the trunks of other blown-down trees. On both sides were sheer drops: on one side was a deep canyon 2000-2500 feet deep and on the other a small valley about 1000-1500 feet deep, the source of the Dapitan River. The ground and the dwarfed and twisted trees were heavily covered with moss. On the top of the peak was a narrow level area about 50 feet wide in some places and densely covered with dwarfed trees. Again, on both sides were sheer drops. 9. Duminagat (5300-5500 feet elevation). There was a small lake by this name in this region. Its area was easily about 6 to 8 hectares (1 hectare is 10,000 square meters), and the water was muddy and deep. The sides were sheer and gave the impression of RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 275 an old water-filled crater. Except for a small creek that was very much filled up with debris there seemed to be no outlet of this small mountain lake. The forests on the mountain sides all around were mid-mountain type, becoming mossy type on the high ridges. The area was very rough. On one side there was a narrow area of sloping land, and on it was an abandoned wooden house that had been built by the Subanos. The steep roof was made of palm leaves. Once upon a time this had been a worship house, but at the time that we were there it was no longer used as such, so anybody who happened to be in the vicinity of the lake could sleep there. The lake was rich in a species of eel, most likely the common Anguilla pacifica that habitually goes up fresh-water streams, deep in the interior of the various islands, and even high up in the moun- tains. There were several Subano fish traps of the basket type that were placed in the water close to the house and baited with the in- testines of birds. The owner came all the way from Gandawan to set these traps. The Habitats on Mount Malindang The area considered here is the northwestern aspect of the moun- tains, from Barrios Salvacion and Buena-Suerte to the summit. Grassland and second growth. From Dipolog, at sea level, to the Buena-Suerte area, about 2500 feet, most of the country is already cultivated and a large part is covered with tall grass or second growth, though perhaps only ten years ago, before the construction of the national road, much of this was lowland forest. Tongues of original forest extend down below these altitudes, and new patches of clear- ing extend into the forest commonly to 3500 feet, so that precise delineation is impossible. Above 3500 feet, clearings are few and of limited extent. Lowland forest. This originally covered the slowly rising plain to 1500 feet and the gently rolling country to 2500 feet, but that area is now second growth and grass. Above this the country becomes rough, and original lowland forest still exists as a solid band at about 3000-3500 feet altitude, though it is much cut up by clearings at its lower edge. This is three-story dipterocarp forest. Transition forest (3500-5000 feet). This is transition diptero- carp-mid-mountain forest, where the three-story character of the forest is no longer very distinct. 276 FIELDIANA: ZOOLOGY, VOLUME 35 Mid-mountain forest (5000-6500 feet). This is two-storied for- est, lacking tall trees that give the third upper story of the lowland forests. Luxuriant epiphytes and mosses begin to grow on the tree trunks and branches. Actually, the type of forest at about 6200- 6500 feet represents a sort of transition mid-mountain-mossy forest type, and the two-story character of the forest is no longer clearly shown. Mossy forest (6500 to near the summit, 7965 feet). This ridge top forest is of low twisted trees, heavily covered with moss. Habitats and Altitudinal Distribution of Birds The grasslands and the second growth, so extensive in the low- lands and already encroaching on the Mount Malindang forests, carry a bird fauna so different from that of the forests that it is ad- visable to consider them separately. The forest birds, judged by their altitudinal distribution, fall into three main groups: Birds of lowlands: sea level to 3000 feet. Birds of hills: 3000 to 6200 feet. Birds of mountains: 3500 feet to near summit (7965 feet). It must, of course, be understood that these altitudes are average and approximate. Local terrain affects this; higher altitude condi- tions descend on ridges; lower altitude conditions ascend in valleys. It must be remembered also that this is a pioneer work on Malin- dang and further work may modify altitudinal limits in some cases. Refinement of groupings is also probable. The single most important dividing line between altitudinal dis- tributions seems to be between 3000 and 3500 feet; a great many lowland-ranging species do not go higher. Above this are two groups of birds: one of the hills and lower mountains and one occurring only where high mountains exist, though both overlap widely on the lower slopes of high mountains. Birds of the Grasslands: Sea Level to 2700 Feet Excalfactoria chinensis, Lanius schach, Megalurus palustris, M. timoriensis, Lonchura leucogaster. Most of the birds of the grassland also enter or perch in second growth shrubbery or isolated shrubs, but only incidentally. One spe- cies, Lanius schach, while living almost entirely in the grasslands, RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 277 where it gets its food, needs shrubs or small trees for perches and for nesting. Many second growth birds range more or less commonly into the shrubbery-grassland. As most of the grasslands of the Philippines are secondary the result of forest destruction, burning, and cultivation the present extent of their habitat is obviously recent. Since there are endemic Philippine subspecies of some of these grassland birds, it is equally obvious that they have lived a long time in the Philippines in small, scattered bits of open habitat such as occur under primitive condi- tions (see discussion below). There is no Mount Malindang endemism in this group. Birds of the Second Growth: Sea Level to about 2500 Feet The following species are typical of the second growth and are not found commonly in the forests except on its margins; naturally most of them go out into hedgerows, scattered shrubs and isolated trees: Centropus viridis (also grasslands), Eurystomus orientalis, Lalage nigra, Pycnonotus goiavier, Oriolus chinensis (sight record). A longer list of forest species commonly go into the shrubbery, such as Phapitreron leucotis, Macropygia phasianella, Chakophaps in- dica, Loriculus philippensis, Dendrocopos maculatus, Coracina striata, Orthotomus atrogularis, Hypothymis azurea, Dicaeum hypoleucum, D. trigonostigma, Dicrurus hottentottus, Zosterops everetti, Sarcops calvus. When forest has been cut down, and the land has been used as corn fields and then abandoned, there is usually a series of changes from grassland to shrubbery; finally, the forest slowly reclaims the area. This may be complicated by impoverished soil that makes forest regrowth difficult; hedgerows may be left between the fields, or solitary trees, or groves. In this confused habitat, most species of the adjacent forest and those of the grassland may occur occasionally. This transition stage between grassland and forest has only a few species common in it. Some actually live in the thick second growth cover, while others such as Eurystomus occupy conspicuous perches from which to hawk for insects; Oriolus chinensis is a clearing and, at most, a forest edge species. Second growth, often of a semi-permanent nature, like the grass- lands, is becoming an increasingly common type of habitat in the Philippines. Some second growth, along beaches, along the winding courses of streams, on erosion gullies, and about marshes, has prob- ably always existed. The birds restricted to this type of habitat are 278 FIELDIANA: ZOOLOGY, VOLUME 35 few, but a certain amount of endemism exists. With the increased area of second growth, a few adaptable forest species also live in it. Birds of the Lowlands and the Mountain Forests: Sea Level to 6200 Feet at Least A few species seem to range widely from the lowlands and up through the mountains, with little regard to habitat: Gallus gallus, Spilornis cheela, Macropygia phasianella, Loriculus philippensis. Birds of the Lowland Forest: Sea Level to about 3000 Feet Accipiter virgatus, Phapitreron leucotis, Chalcophaps indica, Lori- culus philippensis, Surniculus lugubris, Centropus melanops, Otus bak- kamoena, Ninox philippensis, Harpactes ardens, Aceros leucocephalus, Penelopides panini, Dendrocopos maculatus, Mulleripicus funebris, Dryocopus javensis, Coracina striata, C. morio, Irena cyanogaster, Pycnonotus urostictus, Macronus striaticeps, Stachyris plateni, S. capitalis, Phylloscopus olivaceus, Orthotomus atrogularis, 0. cinerei- ceps, Rhipidura superciliaris, Ficedula basilanica, Rhinomyias rufi- cauda, Hypothymis azurea, Prionochilus olivaceus, Dicaeum hypo- leucum, D. trigonostigma, Zosterops everetti, Sarcops calvus, Dicrurus hottentottus, Oriolus xanthonotus. Much of the lowland forest has disappeared in the Philippines generally, and the area about the base of Mount Malindang is no exception. Presumably it was three-storied dipterocarp forest. In 1956 Rabor visited it only from 2700 feet upward. Consequently this list of lowland birds, as far as their lower limit is concerned, is filled in from Rabor's earlier work in the lowlands of Zamboanga Peninsula. Hill Birds: Those Restricted to the Lower and Mid-Mountain Slopes, 3000 to 6200 Feet Pithecophaga jefferyi, Phapitreron cinereiceps, P. amethystina, Ptilinopus occipitalis, *?Columba vitiensis, Hemiprocne comata, *Tri- choglossus johnstoniae, *Prioniturus montanus, Cuculus fugax, Hal- cyon hombroni, Buceros hydrocorax, Chrysocolaptes lucidus, Hypsipetes philippinus, Pachycephala philippinensis, Sitta frontalis, Rhabdornis inornatus, *Dicaeum anthonyi, *?D. nigrilore, D. ignipectus, Arachno- thera clarae. The species marked with an asterisk have the general distribution of true mountain birds. It is interesting that only a few of the birds on this list are more or less true mountain birds and occur only where RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 279 mountains rise to 7000 feet or higher, with a corresponding charac- teristic pattern of distribution (Mindanao, east and west; Negros, Mindoro, Luzon). Most of these birds do not require mountain forest, though here they range well up into it. Elsewhere in the Philippines they live where there are no high mountains, and though they seem to favor some altitude they often occur near sea level elsewhere. Birds Restricted to Mid- and High-Mountain Slopes: 3500-7000 Feet Cacomantis variolosus, *Coracina mcgregori, Lanius validirostris, Brachypteryx montana, *Turdus poliocephalus, Zoothera andromedae, Bradypterus caudatus, *Phylloscopus trivirgatus, *Rhipidura nigro- cinnamomea, *Muscicapa panayensis, *Ficedula westermanni, F. hy- perythra, Aethopyga boltoni, *Zosterops montana, *Apoia goodfellowi, *Hypocryptadius cinnamomeus, *Pyrrhula leucogenys. Species marked with an asterisk are most often met with in the higher elevations, especially on the ridges of the higher peaks. Only one species on this list, Cacomantis variolosus, is a hill bird, rather than a true mountain bird. The rest occur only where high moun- tains exist, even though the birds range down to 3500 feet. Paleogeography In the early Pleistocene, Mindanao was probably divided into five smaller islands that formed an island group comparable to that of the present-day Visayan group. The limits of these Pleistocene Mindanao islands coincided closely with the present elevated parts of Mindanao. The present lowlands correspond to the early Pleisto- cene seas and straits (Moody, in Dickerson, 1928, p. 86). Each of these early Pleistocene Mindanao islands occupied what today is an upland part of Mindanao and each contained a prominent peak; that of Zamboanga included Mount Malindang, then a dom- inant volcano which was belching both lava and ashes. The other early Pleistocene Mindanao islands also comprised prominent peaks that persist as such today. One, in present Agu- san and part of Davao provinces, contained Mount Apo, etc.; one in the present Surigao province included the Diuata Range; one in present Bukidnon and part of Lanao provinces comprised the high plateau and the peaks near Lake Lanao, and one the prominent peaks of Cotabato province. When the level of the ocean lowered, perhaps as much as 90 or 100 meters (Kuenen, 1950; Umbgrove, 1929), the seas and straits 280 FIELDIANA: ZOOLOGY, VOLUME 35 between these five islands became plains and lowlands. At the maxi- mum regression of the Pleistocene seas, Mindanao was larger than it is today; to the north, land connected it with southern Luzon, a land connection that included at least Samar, Leyte and Bohol, while to the south, land connected the then Mindanao via an enlarged Zamboanga Peninsula with Basilan and the Sulu Archipelago, at least. Subsequent raising of the sea level separated them as they are now. The mountains of Mindanao are thus old and have long existed as isolated masses. This has resulted in endemic mountain forms. Mount Malindang and the eastern Mindanao mountains are pre- sumably younger than the Luzon highlands. Possibly this accounts for the lack in Mindanao of north temperate zone elements of flora and fauna that occur in the highlands of northern Luzon; for example, the pine (Pinus) forests and the crossbills (Loxid). Endemism on Mount Malindang The few subspecies of hill birds now known from Mount Malin- dang only, probably will be found to range more widely when more is known about them. Such are Sittafrontalis zamboanga, Rhabdornis inornatus zamboanga, and Arachnothera clarae malindangensis. There is no genus of bird endemic to Mount Malindang, nor is there any endemic species. Thus it has less endemism than do either the Luzon mountains or the eastern Mindanao mountains. We rec- ognize 15 endemic subspecies of mountain birds, all found with other subspecies on other mountains: 1. Trichoglossus johnstoniae pistra Rand and Rabor 2. Prioniturus montanus malindangensis Mearns 3. Coracina mcgregori mcgregori Mearns 4. Lanius validirostris quartus Rand and Rabor 5. Brachypteryx montana malindangensis Mearns 6. Turdus poliocephalus malindangensis (Mearns) 7. Bradyplerus caudatus malindangensis (Mearns) 8. Phylloscopus trivirgatus malindangensis (Mearns) 9. Rhipidura nigrocinrtamomea hutchinsoni Mearns 10. Ficedula hyperythra malindangensis Rand and Rabor 11. Dicaeum anthonyi masawan Rand and Rabor 12. Aethopyga bottom malindangensis Rand and Rabor 13. Apoia goodfellouri malindangensis Mearns 14. Hypocryptadius cinnamomeus malindangensis Rand and Rabor 15. Pyrrhula leucogenys steerei Mearns RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 281 Thus Mount Malindang is an important part of the mountain pattern of bird distribution in the Philippines, but its fauna is appar- ently of less age than that of the mountains of Luzon or of eastern Mindanao, as endemism has proceeded only to the subspecies level. The species probably did not develop in situ in Mount Malin- dang. Probably they arrived as colonists over seas or over lowlands. Some may have evolved, as species, in the eastern Philippines, or they may have colonized from farther afield. This last possibility is suggested by seven species whose relationships lie in several direc- tions: some to the north, some to the southwest, some to the southeast. Mount Malindang may properly be considered a mountain island projecting above water and lowlands. It has received its mountain bird species as present-day species by colonizations from other moun- tains. The clue to their further origin lies in an analysis of the mountain birds of Luzon and eastern Mindanao, a study that one of us, Rabor, has in hand. In only a few cases the mountain birds of Mount Malindang do not show subspecific differentiation as compared with the nearest populations elsewhere in the Philippines. This is illustrated by Columba vitiensis, Zoothera andromedae, Muscicapa panayensis, Ficedula westermanni, and Dicaeum ignipectus. Relationships of the Mountain Birds There are about 20 species of mountain birds occurring on Mount Malindang, with a number more doubtfully classified as hill birds. Both the endemic and the non-endemic mountain birds have repre- sentatives on one or more of the other important high mountains in the Philippines (in eastern Mindanao, Negros, Mindoro, northern Luzon), and a few are found elsewhere. None of the mountain birds is closely enough related to lowland birds now living at the base of Mount Malindang to suggest the pos- sibility that any of them has arisen in situ from present-day lowland representatives. On the other hand, the occurrence of the endemic Philippine spe- cies on several Philippine mountains, none of which has been part of one mountain chain, the way most of them stay at their altitudinal range, and the range of the non-endemic species on mountains outside the Philippines strongly suggest that colonization of the mountain has provided Mount Malindang with its avifauna. Part of this could have come from eastern Mindanao, judging by the Mindanao en- 282 FIELDIANA: ZOOLOGY, VOLUME 35 demic species represented, such as Trichoglossus johnstoniae, Coracina mcgregori, Aethopyga boltoni, Apoia goodfellowi, and Hypocryptadius cinnamomeus. Though the rest could also have colonized by way of eastern Min- danao, their more distant relationships are obvious. Part could have come from the Sunda Islands, as indicated by the non-endemic Zoo- thera andromedae; part from the islands to the south and east, as indicated by Turdus poliocephalus and Phylloscopus trivirgatus; and part from the north, as indicated by Ficedula westermanni, which also ranges in southern Asia, where the inter-specific relatives of Lanius validirostris and Pyrrhula leucogenys also live. The several Philippine endemic species that range on the more northern islands could also have colonized Malindang directly from the northern islands. List of Species The collection made in 1956, containing 92 species represented by about 900 specimens, is now in Chicago Natural History Museum and is reported on here. A few duplicates (not listed here) were re- tained in the Silliman University collection. The lowland collection of birds that normally do not range above 3000 feet is incomplete, as most of the party's efforts were directed toward collecting the birds from 3000 feet up. Good series were secured of most of them, though a few continue as rarities, such as Bradypterus caudatus malindangensis, Pyrrhula leucogenys steerei, and Lanius validirostris quartus. Family ARDEIDAE. Herons. *Gorsachius goisagi (Temminck) Specimen: 1 cf adult; 3500-4500 feet altitude. Wing, 261; exposed culmen, 37 mm. Weight, 527.1 grams. This is an adult with the crown dull black. It has the measure- ments (long wing, short bill) and the black and rufous axillaries of this species. The specimen, the only one seen, was taken on the ground in dense forest, by a small stream. Family ACCIPITRIDAE. Hawks. Accipiter virgatus confusus Hartert Specimen: 1 9 subadult; 3500-4500 feet altitude. Wing, 170 mm. Weight, 131.3 grams. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 283 Pithecophaga jefferyi Ogilvie-Grant Specimen: 1 rf 1 adult; 4500-5500 feet altitude. Wing, 581 mm. Weight, 4041.2 grams. Shot from a high tree in original forest. Only one other was seen, a male collected at Masawan and now in Silliman University col- lection. It was being mobbed by a number of hornbills. Spilornis cheela holospilus (Vigors) Specimens: 1 o' / Hypocryptadius cinnamomeus vl U.~ Uct ................... \ -.-. j . . , . \ Rhipidura mgrocinnamomea Ka-lam-bang-ai ............ Parus elegans La-la-si ................... Macronus striaticeps Lam-bong-on .............. Centropus melanops Li-bod-li-bod .............. Sitta frontalis Li-mu-con ................ Phapitreron leucotis Lo-ki-lok ................. Pycnonotus goiavier Man-o-tot ................ Phapitreron amethystine Mang-git' ................. Accipiter species Pi_pjt' ! Dicaeum species \ Nectarinia species Pis-tra' ................... Trichoglossus johnstoniae Sa-ki-kap ................. Dicrurus hottentottus g}_ ao ' / Zoster ops species \ Phylloscopus species Si-wil' .................... Mulleripicus funebris Su-lak' ................... Megalurus species Ta-li-sa-i' ................. Coracina species Ta-li-sen' ................. Coracina species Ti-bay' ................... Hypsipetes species To-ko-wao' ................ Macropygia phasianella Tong-ga-ek' ............... Prioniturus species Tong-i-lao ................. Oriolus xanthonotus RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 309 SUBANO NAMES FOR MOUNT DAPIAK BIRDS Al-pi-sao' Dicrurus hottentottus A-lo' Bolbopsitlacus lunulatus Ba-ba-sa Ixobrychus cinnamomeus Be-ned' Microhierax erythrogenys Bu-wa-wa Pitta erythrogaster Da-lam-bung-an Centropus melanops Da-lang-gi-tan Arachnothera clarae Du-ma-lan Collocalia species Ma-ne' Orthotomus atrogularis p. - t , f Dicaeum species ' \ Nedarinia species Si-bu-kok Centroptis viridis Ta-gip-tip' Penelopides panini Ta'-men-tes Halcyon species Ung-ek' Aceros leucocephalus Birds of Bohol Island Introduction The 1955 Chicago Natural History Museum-Silliman University Bohol Zoological Expedition, headed by D. S. Rabor, worked in the field from March 28 to May 18. The hard rains which began in earnest about the middle of May cut short the collecting activities of the party. The members of the Expedition were mainly Silliman University Biology Department faculty, students and assistants. Itinerary of the Expedition March 27: Departure by steamer from Dumaguete City, Negros Oriental (Silliman University), for Tagbilaran, Bohol; arrival in Tag- bilaran in the afternoon; arrival by truck in Sierra Bullones late in the evening. March 28: Departure by truck for Sandayong (altitude 300-350 meters), about 5 kilometers from Sierra Bullones, where camp was established. March 28-April 13: Collecting conducted by party in Sandayong and surrounding localities within a radius of about 5-8 kilometers, including the sitios and barrios of Canlangit, Luyo-Wahig, Lataban, Danicop, Duwao, Pamaksalan, and Abakhanan. April 13: Main collecting party transferred on foot to a subcamp in Barrio Cantaub (altitude 700-750 meters), about 10 kilometers farther in the mountainous areas of Sierra Bullones. At Sandayong, in the main camp, three members were left behind to requisition sup- plies, continue collecting, and keep the flow of needed supplies to Cantaub subcamp. April 13-May 12: Collecting conducted by party in Cantaub and adjacent localities including the sitios and barrios of Danicop, Abak- hanan, Anislagan, all of Sierra Bullones; Badiang and Cogonon, of the municipality of Guindulman; and Mayana, of the municipality of Jagna. May 12: Departure of party on foot early in the morning for the main camp at Sandayong; arrival late in the afternoon. 310 RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 311 May 13-18: Collecting conducted by party in Sandayong and surrounding localities within a radius of 10 kilometers. May 19: Departure by truck for Sierra Bullones in the afternoon; arrival in the poblacion in the evening. May 20: Departure by truck for Tagbilaran early in the morning; arrival there at noon ; departure by steamer in the afternoon ; arrival in Dumaguete City, Negros Oriental, late in the evening. Description of Collecting Sites SANDAYONG CAMP (300-350 meters altitude). The main camp was established at Sitio Sandayong, about 5 road kilometers from the town of Sierra Bullones, among the hills. The tents were set under a large balete tree (Ficus sp.), beside the Jagna-Sierra Bullones road, which was under construction at the time. This tree was the only one of its kind that was left standing in the area, which other- wise was cleared and cultivated, or was overgrown by tall grass. Because of its interesting history and the numerous superstitions connected with it, this tree was never touched by the laborers of the road project. In fact, the road was made to swerve a little from its true course so the tree would be left unharmed. Fairies and spirits, both good and evil, were reputed to have lived in the tree. The people used to offer gifts every time that they passed it on their way to and from the town. Passersby said that they had heard beautiful music coming from it. Others claimed to have seen queer animals under it. The collecting party unintentionally put a stop to all these beliefs when without knowing the local stories the camp was established under the tree. Two hundred meters from the camp site, there was a patch of well-logged original forest, about 30 hectares in area, that covered the side and ridge of a high hill that rose about 50 meters above the level of the camp site. Immediately around the site was a small level area drained by a creek originating in the forest patch nearby. Part of this area contained rice fields about one hectare in size. The rice plants were growing luxuriantly at the time that we were there, in spite of the fact that it was very dry and hot in surrounding places that did not have the benefit of this small creek. The entire area had been originally a government forest preserve and had been much larger five years earlier. Gradually, the people had cut down the forest and prepared kaingin clearings and planted the cleared areas, at least for a few seasons, to sweet potato, cassava, corn and rice, in the favorable spots near water. 312 FIELDIANA: ZOOLOGY, VOLUME 35 The remaining forest patch was transition dipterocarp-molave type, and throughout the years the people had logged the valuable timber trees for use in the construction of their houses, in spite of the government regulations against cutting down any of the forest. The forest patch was the only one of some size in the locality, al- though there were other patches of original forest on the distant hilltops, but of very much smaller areas. All around were grass and clearings that were often left to grow to second growth or to grass. Collecting was carried on mainly in this forest patch and in other small forest patches for a radius of about 5 to 8 kilometers, at alti- tudes varying between 200 and 600 meters. CANTAUB SUBCAMP (700-750 meters altitude). Camp was estab- blished in the one-room schoolhouse, which was not occupied, since it was vacation time. This building was situated on a low hill, at the edge of the forest and was set apart from the rest of the barrio houses. Two hundred meters away, the forest began. This forest was also the transition dipterocarp-molave type. Cantaub is really located on a plateau which must be a part of the oldest marine terrace in the interior of the island. The forested hills represent the ridges of old hills which have been eroded, and the erosion material deposited between them has formed small, level valleys. All the places with enough water were cultivated into wet rice fields. The drier areas were covered with tall grass; both cogon (Imperata cylindrical and talahib (Saccharum spontaneum) were abun- dant. From time to time, the residents burned down these grass tracts and planted them to corn, sweet potato or cassava. Then, after two or three seasons, they abandoned the cleared areas again. On the ridges and sides of the low hills and mountains, original forests formed an elongated tract about 10 kilometers in length and about 1 kilometer or less in width. In places, clearings had been made in this forest. It is possible that the forest tract covered some five thousand hectares, but the area was rapidly getting smaller be- cause people were making clearings for kaingin cultivation. On the ridges of the higher hills and mountains, the forest ap- proached the mid-mountain type, but the altitude was not high enough for the development of a real mid-mountain forest. There were tracts of Casuarina sp. on the ridges and mountain sides, mixed with other species but dominant. The forest was nowhere distinctly three-storied as would be the case of real dipterocarp forest, but there was a very close approach to it. The area was limestone and the molave-dipterocarp forest type flourished best in this type of country. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 313 There were several caves and tunnels, as would be expected in limestone areas, and these were duly explored and collected in. The greater part of the forest tract belonged to the town of Sierra Bullones and small parts to Guindulman and Jagna. History of Bird Collections A. H. Everett and his brother were the first collectors who worked on Bohol Island. Everett himself collected in Talibon, in the north- ern part of Bohol, and in the adjacent localities for only about one week. Then he left for Palawan, leaving his brother to continue col- lecting in the interior during October and November, 1877. Here the brother "found a country covered with grass 12 feet high, and with no forest except on the tops of a few hills. Birds were scarce; and he had to return stricken with fever" (Tweeddale, 1878, p. 708). Representatives of 47 species were collected by the Everetts in north- ern Bohol. In March, 1888, some members of the Second Steere Expedition collected on Bohol. Fourteen species were taken, of which 7 were new records for the island. In March and April, 1906, Celestino and Canton collected on Bohol, and later on, in May, McGregor joined them. The party worked in the localities around Tagbilaran, where they found no more forest. They moved to Corella, Sevilla and Balilijan, where there were still small remnant patches of forest on some of the moun- tain tops. Finally they moved to Guindulman, on the southeastern part of the island, and collected in a remnant patch of original forest on top of a limestone ridge. Ninety-one species were collected, in- cluding 5 which were supposedly new; many new records for the island were established, raising the number of birds known on Bohol to 147 (McGregor, 1907). Of this number 117 were resident, 28 mi- grant, and 2 of doubtful status. The 1955 expedition party collected in the remnant forest patches on the hills and mountains of Sierra Bullones, especially around Sitio Sandayong and Barrio Cantaub and the adjacent localities, in an area that roughly approximated a triangle, formed by the municipal- ities of Sierra Bullones toward the interior and Guindulman and Jagna toward the coast, all in the southeastern part of Bohol Island. A total of 1250 bird specimens was collected, including 109 forms, of which 98 are resident and 11 migrant. Twenty-five forms are re- corded for the first time from Bohol; of these 21 are resident and 314 FIELDIANA: ZOOLOGY, VOLUME 35 4 migrant. The present collecting has increased the avifaunal list of Bohol to 172 forms, of which 137 are resident, 32 migrant, and 3 of doubtful status. Five new races have been described from Bohol in other papers (Rand and Rabor, 1957, 1959). Four of the species to which these races belong were included in the list of McGregor, and one was collected for the first time on the island by the 1955 collecting party. The following is a list of the resident forms which have been re- corded for the first time from Bohol Island: 1. Anas luzonica 12. 2. Perm's celebensis steer ei 13. 3. Accipiter virgatus confusus 14. 4. Falco severus 15. 5. Excalfactoria chinensis lineata 16. 6. Rallus torquatus torquatus 17. 7. Rallina eurizonoides eurizonoides 18. 8. Treron pompadora axillaris 19. 9. Ptilinopus occipitalis 20. 10. Cacomantis variolosus sepulcralis 21. 11. Surniculus lugubris velutinus Ninox philippensis centralis Batrachostomus Septimus septimus Eurostopodus macrotis macrotis Collocalia inexpectata amelis Hemiprocne comata comata Ceyx argentatus flumenicolus Eurylaimus steerii samarensis Irena cyanogaster ellae Ptilocichla mindanensis fortichi Oriolus xanthonotus samarensis The newly recorded migrant forms are the following: 1. Gallinago megala 2. Cuculus saturatus horsfieldi 3. Monticola solitaria philippensis 4. Locustella lanceolata Geography Bohol Island, lying directly east of the southern half of Cebu, is roughly ovate in form. It measures about 85 kilometers along its east-west axis and 60 kilometers along its north-south axis. It is tenth in size of the larger islands of the archipelago, with an area of about 3973 square kilometers (1534 square miles). Of the 30 to 40 larger and medium-sized islands, Bohol is one of three which have no high mountain peaks (Samar and Masbate are the other two). From a central height of about 800 meters altitude, the island is well drained on all sides. Because of the absence of any high mountain range, it receives a more or less well-distributed rain- fall throughout the year. Since it is sheltered from the full effects of the northeast monsoon by Leyte and from those of the southwest monsoon by Negros and Cebu, the resulting precipitation is much less than that of Samar. Bohol is one of three larger islands which have been excessively deforested and rendered barren throughout the past years (Cebu and Panay are the other two). At present a greater part of the land RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 315 area is covered with grass, the result of man's activities. Worcester and Bourns (1898, Proc. U. S. Nat. Mus., 20, no. 1134, p. 580) aptly express this deforested condition of Bohol when they write: "The relationship of the birds of Bohol is difficult to determine, as the last trace of virgin forest seems to have long since been swept from the island, and with its disappearance a considerable part of the record of Bohol's past, as furnished by its birds, has been forever blotted out." Up to the present, however, there are still two important areas of remnant original forest in the interior of Bohol and several small patches on scattered hills and mountain tops, also in the interior. None of these tracts is visible from the sea, thus making the island appear entirely deforested and barren when viewed from a ship, and very discouraging from the ornithological collecting point of view. This unpromising appearance may explain the small number of orni- thological collectors who were attracted to work on Bohol, and hence the lack of collected material from this island, even up to 1955. Geology and Paleogeography Bohol, together with Cebu, Negros, Panay and Mindoro rests on the Central Philippine Platform or Central Plateau (Bailey Willis, 1937, see map). Willis (1937, p. 34), commenting on the geology of Bohol, writes: "It has a central mass of plutonics, which is to a large extent covered by Pliocene and Recent coral. It is obviously raised. Fly- ing over its southwestern coast I observed the flatness of the plateau, which represents the level of the coral reef as it grew beneath the sea. It is not a peneplain. Erosion has produced the well known 'hay- cock hills' whose even summits represent hard masses in the original level, now isolated from one another by erosion of valleys between them. The valley floors were cut out to a common level that was controlled by sea level during a pause in the progress of the uplift. Hence the uniformity in height and general form of the 'haycocks.' "The apparent flatness of Bohol seems to indicate that the condi- tions of elevations have differed from those that have affected Cebu. Instead of arching the island the uplift seems to have been more uniform." Dickerson (1928, p. 36) writes: "In all probability Bohol, like Samar, has been rather recently elevated from the sea, and the streams have not yet been able to remove completely the traces of marine plains that border these islands." 316 FIELDIANA: ZOOLOGY, VOLUME 35 Terraces about 120 or 150 meters in elevation occur on Bohol. The abundance of coralline limestone and marl and the presence of a well-marked marine terrace over the southern half of Bohol indi- cate that only a small part of Bohol was above sea level during the Pleistocene. It is possible that most of Bohol was covered during the early Pleistocene by the shallow water of a sea (Dickerson, loc. cit.). After the succession of uplifts in the middle or late Pleistocene, Bohol began to assume its present form. In the mountainous regions of the eastern and southeastern parts of Bohol, in an area that is bounded on the west by an imagi- nary straight line that passes inland and extends between the towns of Ubay in the northeast and Valencia in the south, plutonic rocks occur that have been positively identified as serpentine (Irving, 1953). The same type of rock has been identified in the mountains between the towns of Jagna and Sierra Bullones. In the central parts, middle Miocene conglomerates, middle Mio- cene sandstones, and Pliocene limestone have been identified. The mountains of Sierra Bullones, the site of a greater part of the collect- ing in 1955, are upper Miocene limestone. In the coastal areas Plio- cene limestone and Pleistocene undifferentiated sediments occur (Irving, op. cit.). Dickerson (1928) visualizes the Philippine Islands some time dur- ing the Pleistocene as comprised of a few large islands, only four or five in number, among which was one which included what at present are northeastern Mindanao, Bohol, Leyte, Samar, and the entire southern part of Luzon, from the narrow neck of Quezon Province southward, including the islands of Marinduque and Catanduanes. It is, however, possible that at the maximum regression of the Pleistocene glaciations, when the level of the oceans was lowered in this part of the world by as much as 90-100 meters (Kuenen, 1950; Umbgrove, 1929), a much larger area was exposed than what is now occupied by present-day Mindanao and the nearby islands of Bohol, Leyte, Samar, and other much smaller ones. At about this time, land connections probably were existing between the Bohol-Leyte- Samar land mass (all connected at the time) and Luzon in the north (through southern Luzon), and Mindanao in the south. The connec- tions were with Samar, through northwestern Samar and southern Luzon in the north, and southeastern Samar and northeastern Min- danao in the south. At that time Bohol formed the terminal half of a peninsula that jutted out of a large eastern island consisting of part of Luzon, Samar, Leyte, Bohol, Mindanao, Basilan and the Sulu RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 317 Archipelago. This peninsula was formed of what is now the southern half of Leyte and the plain that was then occupying what is now the sea between present-day Leyte and Bohol, and Bohol itself, forming the end part. Also, Zamboanga Peninsula, then much broader and longer than it is at present, was continuous with Basilan and with Sulu Archipelago, which then was one continuous land mass. So this Pleistocene island extended from the present-day northern Luzon, to Samar-Leyte-Bohol, to northeastern Mindanao, to the present-day Mindanao Island, down to Zamboanga Peninsula, to Basilan, and to the Sulu Archipelago as one continuous land mass, located mainly on the eastern part of what is now the Philippines and curving south- westward and coming very close to Borneo. Subsequent develop- ments resulted in the separation of the various islands as they are today. With this paleogeographic picture in mind, the close relationships in the avifaunas of the different islands of the Eastern Province, which at present consists of Luzon, Samar, Leyte, Bohol, Mindanao and Basilan, and the small islands immediately adjoining Polillo, Catanduanes, Marinduque, Biliran, Panaon, Dinagat, Siargao and Camiguin South will be better understood. At about the time that Bohol, Leyte and Samar formed the mid- dle portion of the great eastern island, another large island existed in the central Visayas. This island consisted of Negros, Panay, Gui- maras, Masbate, Ticao, Tablas, Romblon, Sibuyan and Bantayan. Between these two large islands lay Cebu, which at the time was a string of small coral islands, remaining as such until late Pleistocene, when they united into present-day Cebu Island. Zoogeography McGregor (in Dickerson, 1928, pp. 198-213) considered the islands of Bohol, Leyte and Samar, and the small islands that are adjacent, such as Biliran and Panaon, as forming a distinct subprovince, based on the similarity of their avifaunas. Delacour and Mayr (1946, pp. 9-12) grouped several of the original subprovinces of McGregor, consisting of the islands along the eastern part of the Philippine archi- pelago from Luzon down to Mindanao and Basilan and the islands between them, and placed them under a larger category, the Eastern Province, as separated from the Central or Visayan Province, the Palawan Province and the Marginal Districts, comprised of the is- lands on the periphery of the Philippines that come in contact with the main faunal areas that comprise the provinces. 318 FIELDIANA: ZOOLOGY, VOLUME 35 Grouping the original hydrographic units comprising Samar, Leyte, Bohol, Camotes, Biliran and Panaon, with the rest of the islands of the Eastern Province, does not in any way detract from the fact that the above-mentioned islands show among themselves the closest relationship in their avifaunas, when compared to other islands nearby, such as Luzon and Mindanao and Basilan, which also belong to the same zoogeographic province. Based on the fact that Mindanao and Basilan used to be important components of the southern portion of the large Pleistocene island which also included Bohol, Leyte and Samar, and Luzon in the north, close relationships between the avifaunas of these three subdivisions are to be expected. Thus, bird forms should be closer among the Luzon unit (Luzon and nearby small islands of Polillo, Catanduanes, Marinduque), the Bohol-Leyte-Samar unit (and the small islands nearby), and the Mindanao-Basilan unit (and the small islands nearby), than between any one of these three units and any other province, either the Cen- tral Province or Palawan Province. Eleven forms are found only on Bohol, Leyte and Samar: Loric- ulus philippensis worcesteri, Harpactes ardens linae, Ceyx argentatus flumenicolus, Buceros hydrocorax semigaleatus, Penelopides panini samarensis, Dendrocopos maculatus leytensis, Eurylaimus steerii sama- rensis, Coracina striata boholensis, Irena cyanogaster ellae, Orthotomus samarensis, and Rhipidura superciliaris samarensis. Three forms are found on Bohol, Leyte, Samar, and the nearby islands of Biliran and Panaon, which by their present location are really part of the Bohol-Leyte-Samar hydrographic unit: Dryocopus javensis pectoralis, Chrysocolaptes lucidus rufopunctatus, and Dicaeum hypoleucum pontifex. Eight forms are found on Bohol, Leyte, Samar, Mindanao and Basilan and may also be found on the small islands between, such as Panaon and Dinagat: Centropus melanops, Otus bakkamoena ever- etti, Batrachostomus s. septimus, Orthotomus atrogularis frontalis, Pri- onochilus o. olivaceus, Dicaeum trigonostigma cinereigulare, Arach- nothera longirostris flammifera, and Dicrurus hottentottus striatus. Only one form is found on Bohol, Leyte, Samar, Luzon and the small islands near them, such as Polillo, Marinduque, Panaon and Dinagat: Phapitreron amethystina amethystina. Two forms are found on Bohol which are definitely Central Prov- ince in relationship: Spilornis cheela panayensis and Ninox philip- pensis centralis. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 319 One form is found on Bohol, Luzon, Mindoro, Panay and Minda- nao: Porphyrio pulverulentus. One form is found on Bohol, Leyte, Samar, Biliran and Siquijor: Phapitreron leucotis albifrons. The closely related form, P. I. brevirostris, is found on Mindanao. Only one form is found on Bohol and Luzon : Acrocephalus stento- reus harterti. Seven forms are recognized as endemic on Bohol : Turnix sylvatica celestinoi, Ptilocichla mindanensis fortichi, Macronus striaticeps boho- lensis, Stachyris nigrocapitata boholensis, Rhinomyias ruficauda boho- lensis, Aethopyga pulcherrima decorosa, and Zosterops everetii boholensis. All the endemic races on Bohol are represented by closely related forms on the nearby islands of Leyte, Samar, Mindanao and Basilan : Turnix sylvatica masaaki (Mindanao), Ptilocichla mindanensis minuta (Leyte, Samar), P. m. mindanensis (Mindanao), P. mindanensis basi- lanica (Basilan), Macronus striaticeps cumingi (Samar), M. striaticeps mearnsi (eastern Mindanao, west to Mount Malindang in Zambo- anga Peninsula), M. striaticeps mindanensis (southern part of Zam- boanga Peninsula of Mindanao), M. s. striaticeps (Basilan), Stachyris n. nigrocapitata (northern Leyte, Samar), Rhinomyias ruficauda sama- rensis (Samar, Leyte, eastern Mindanao), R. ruficauda, zamboanga (western Mindanao), R. r. ruficauda (Basilan), Aethopyga p. pul- cherrima (Leyte, Samar, Dinagat, Mindanao, Basilan), and Zosterops everetti basilanica (Leyte, Samar, Dinagat, Mindanao, Basilan). Since Bohol is at the tip of what was once a peninsula, it may have afforded a good place for subspeciation to take place relatively undis- turbed by the mixture of populations that occurred on what later became Leyte and Samar, which were in more direct contact with Mindanao on one end and Luzon on the other. Leyte and Samar must have separated later because even to the present day the very narrow San Juanico Strait that separates Leyte and Samar is not an effective barrier for bird exchange between the two islands. The absence of Parus and Sitta on Bohol is remarkable. Parus is also absent on the nearby islands of Leyte and Samar. Sitta, how- ever, has been recorded on both Leyte and Samar. It will not be strange if the genus is eventually found on Bohol. Rhabdornis inornatus has not been recorded so far from Bohol al- though it has been found on Leyte and Samar. It may eventually be found on Bohol. 320 FIELDIANA: ZOOLOGY, VOLUME 35 The Eastern Province, based on the affinities of the bird forms found on the various islands comprising the unit, may easily be shown to contain three subdivisions: 1. Luzon (together with Marinduque, Polillo, Catanduanes and other small islands nearby). 2. Bohol-Leyte-Samar (together with Biliran, Panaon, Dinagat). 3. Mindanao-Basilan (together with small islands nearby). List of Species The 172 forms recorded from Bohol are listed below. The earlier records are from McGregor (1909). Family PODICIPEDIDAE. Grebes. Podiceps ruficollis philippensis (Bonnaterre) Collected by McGregor. Family ARDEIDAE. Herons, Bitterns, etc. Ardea sumatrana Raffles Collected by McGregor. Ardea purpurea manilensis Meyen Collected by McGregor. Egretta intermedia intermedia (Wagler) Collected by Steere Exp. Egretta garzetta garzetta (Linnaeus) Collected by Everett and McGregor. Demigretta sacra sacra (Gmelin) Collected by Steere Exp. and McGregor. Bubulcus ibis coromandus (Boddaert) Collected by Everett and McGregor. Butorides striatus carcinophilus Oberholser Collected by McGregor. Nycticorax caledonicus manillensis Vigors Collected by McGregor. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 321 Ixobrychus cinnamomeus (Gmelin) Collected previously by McGregor. Cantaub, Sierra Bullones, 700-750 meters altitude; 1 d", 1 9 im- mature, May 5-10. Wing, d" 141; 9 immature 139. Culmen from frontal feather- ing, d" 46.5; 9 immature 48.5 mm. Weight, d" 106.2; 9 immature 116 grams. Family CICONIIDAE. Storks. Dissoura episcopus episcopus (Boddaert). Collected by Steere. Family ANATIDAE. Ducks. Dendrocygna arcuata arcuata (Horsfield) Collected by Everett and McGregor. Anas luzonica Fraser Cantaub, Sierra Bullones, 700-750 meters altitude; 1 d", 1 9 ; May 11. Wing, d 1 256; 9 240. Culmen from frontal feathering, d* 53; 9 49 mm. Weight, d" 803.5; 9 764 grams. First record of the species from Bohol. Bohol birds do not differ from Negros, Mindanao and Samar specimens. The female has the rectrices molting in May. The male has the testes enlarged in May. Family ACCIPITRIDAE. Hawks. Elanus caeruleus hypoleucus Gould Collected by McGregor. Pernis celebensis steerei Sclater Sandayong, Sierra Bullones, 300-350 meters altitude; 1 d" ; April 8. Wing, 363. Culmen from base, 37.5 mm. Weight, 696.5 grams. First record of the species from Bohol. The Bohol male does not differ significantly from Negros and Mindanao males. 322 FIELDIANA: ZOOLOGY, VOLUME 35 In a fully adult male from Ayuquitan, Negros Oriental, the entire under parts are white and the dark brown streaks on the forehead and forecrown have disappeared except for the dark brown on the feather shafts. Apparently the rufous parts of the feathers on the head gradually wear off, leaving only the blackish brown and black streaks on the shaft and part of the vanes on the terminal part of the feathers. These, too, gradually wear off, leaving only the dark brown shafts on the terminal parts, but the white parts of the feather on the basal parts are intact. The feathers on the throat and fore- breast gradually lose their dark brown or blackish brown streaks on the center of the terminal half, leaving only the white basal half and the blackish brown or dark brown feather shaft. The fully adult male does not have any brown barring on the flanks and thighs. The female has the well-pronounced black or blackish brown streaks on the head and on the breast; the younger the specimen the more pronounced these streaks. The flanks, thighs, and under tail coverts show clear barring of brown. In the series of six males and three females in Chicago Natural History Museum, three males and one female show molt only in the primaries in April, May and June; one female shows molt in the pri- maries in October; two males and one female show molt only in the rectrices in May and June, and one female shows molt in the rectrices in October. Color of unfeathered parts when fresh: iris bright yellow; legs and feet bright yellow; nails blackish brown; upper mandible dark brown, lower mandible dark brown, very pale brown at basal part. Haliastur Indus intermedius Blyth Collected by Steere Exp. and McGregor. Accipiter virgatus confusus Hartert Sandayong, Sierra Bullones, 300-350 meters altitude; 1 d" ; April 3. Cantaub, Sierra Bullones, 700-750 meters altitude; 1 of ; April 27. Wing, c? (2) 151.5, 157. Culmen from base, cf (2) 19, 19 mm. Weight, d" (2) 94.5, 93.6 grams. Recorded for the first time from Bohol. The two Bohol males are in fresh full adult plumage. The barring on the under parts is represented by very faint remnants on the abdo- men. The brownish line along the center of the chin and throat is very much reduced. Both Bohol birds were taken inside original forest patches. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 323 Butastur indicus (Gmelin) Collected by Everett and by Steere Exp. Haliaeetus leucogaster (Gmelin) Collected by McGregor. Circus melanoleucos (Pennant) Collected by McGregor. Spilornis cheela panayensis Steere Collected by McGregor. Sandayong, Sierra Bullones, 300-350 meters altitude; 1 d" ; April 1. Cantaub, Sierra Bullones, 700-750 meters altitude; 1 9 ; May 3. Lataban, Sierra Bullones, 700-750 meters altitude; 1 9 ; May 10. Wing, cf 325; 9 324, 329. Culmen from base, d" 36; 9 36, 36 mm. Weight, tf 522; 9 484.5, 564 grams. One male and one female from Bohol fall within a series of 14 specimens of S. c. panayensis from Negros and Romblon. Another female from Bohol is much darker and approaches a series of 13 specimens of the darker-colored S. c. holospilus from Mindanao. The measurements of the 3 Bohol birds most closely approach those of S. c. panayensis. Family FALCONIDAE. Falcons. Microhierax erythrogenys (Vigors) Collected by McGregor. Falco severus Horsfield Sandayong, Sierra Bullones, 300-350 meters altitude; 1 cf , 1 9 ; March 29. Wing, d 1 221; 9 238.5. Culmen from base, d" 23.5; 9 24.5mm. Weight, c? 183; 9 249.2 grams. First record for Bohol. Family PHASIANIDAE. Pheasants, Quail, and Jungle Fowl. Excalfactoria chinensis lineata (Scopoli) Cantaub, Sierra Bullones, 700-750 meters altitude; 1 9 ; April 19. Wing, 70. Culmen from base, 11.5 mm. Weight, 23.1 grams. First record of the species from Bohol. 324 FIELDIANA: ZOOLOGY, VOLUME 35 *Gallus gallus gallus Linnaeus Collected previously by McGregor. Canlangit, Sierra Bullones, 300-350 meters altitude; 1 cf imma- ture; May 16. Cantaub, Sierra Bullones, 700-750 meters altitude; 1 9 ; May 11. Wing, 9 188 mm. Weight, 9 666.2 grams. The half-grown male can easily be mistaken for the half-grown male of the native domestic breed. Family TURNICIDAE. Button-Quail. Turnix sylvatica celestinoi McGregor Collected by McGregor. Family RALLIDAE. Rails, etc. Rallus torquatus torquatus Linnaeus Sandayong, Sierra Bullones, 300-350 meters altitude; 1 9 ; May 17. Wing, 152. Culmen from base, 41.5 mm. Weight, 241 grams. Recorded for the first time from Bohol. The Bohol specimen is similar to specimens from Negros, even in measurements; hence it is placed in the race torquatus. The species was fairly common among the grassland areas in the localities in which we worked, but it was more often heard than seen. Rallina eurizonoides eurizonoides (Lafresnaye) Cantaub, Sierra Bullones, 700-750 meters altitude; 1 c? ; April 15. Wing, 137. Culmen from base, 27.5 mm. Weight, 111.7 grams. First record of the species from Bohol. The unfeathered parts when fresh have the following colors: iris reddish orange; bill blackish on upper portion of upper mandible to tip, olive green on lower portion and lower mandible; legs, feet and nails dark gray. *Poliolimnas cinereus ocularis (Sharpe) Collected by McGregor. Amaurornis olivacea olivacea (Meyen) Collected previously by McGregor. Sandayong, Sierra Bullones, 300-350 meters altitude; 2 cf , 1 9 , sex? immature; April 1-3. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 325 Wing, d" 166, 168; 9 154. Culmen from base, rf 1 41, 41; 9 37.5 mm. Weight, cT 292.5, 312.5; 9 250 grams. A young downy chick, at most a few days old, was collected on April 3 along the side of a new road that was made on the shoulder of a hill. Tall grass covered the whole area. The chick apparently fell down the steep side of the cut bordering the new road, and both parents in their concern came out into the road, where they were all captured. These birds seem to prefer the drier parts of grassland areas be- cause they have been taken far from any creek or water area. Amaurornis phoenicurus javanica (Horsfield) Collected previously by McGregor. Sandayong, Sierra Bullones, 300-350 meters altitude; 2 9 ; May 15-17. Wing, 134, 140. Culmen from base, 33, 34 mm. Weight, 166.5, 180.5 grams. The species prefers tall grass in swampy and marshy areas. Cogo- nales, where there are small creeks crisscrossing the area, are favorite habitats. Gallicrex cinerea (Gmelin) Collected previously by McGregor. Cantaub, Sierra Bullones, 700-750 meters altitude; 7 d\ 3 9 adults, 1 9 young adult; April 14-May 11. Wing, d" (7) 212-242 (av. 228.6); 9 (3) 199-225 (av. 208) mm. Weight, d* (7) 476-650 (av. 546.1); 9 (3) 297.5-434 (av. 355.5) grams. The male birds from Bohol are in different degrees of changing to summer plumage. One male taken on May 5 had the change to summer dress almost completed except for parts of the back, abdo- men, crissum, and under tail coverts. Male birds taken in Chekiang, China, were in complete breeding plumage in May and June. A fully adult male taken in Negros Island on August 2 has the breeding plumage mixed with the non-breeding plumage. It should be an interesting study to find out if the Philippine birds of this spe- cies ever attain a full breeding dress like that of the Chinese birds. Four males and one female had enlarged gonads in April and May. Gallinula chloropus orientalis Horsfield Collected by McGregor. 326 FIELDIANA: ZOOLOGY, VOLUME 35 Porphyrio pulverulentus Temminck Collected by McGregor. Family CHARADRIIDAE. Plovers. Squatarola squatarola (Linnaeus) Collected by McGregor. Pluvialis dominica fulva (Gmelin) Collected by Everett. Charadrius dubius dubius Scopoli Collected previously by Everett. Canlangit, Sierra Bullones, 300-350 meters altitude; 1 9 ; May 14. Wing, 109.5. Culmen from base, 20 mm. Weight, 31.7 grams. The species was met with occasionally in the gravelly beds of the shallow streams of the area. Charadrius alexandrinus dealbatus (Swinhoe) Collected by Everett and by Steere Exp. Charadrius peronii peronii Schlegel Collected by Everett. Charadrius mongolus mongolus Pallas Collected by Everett. Charadrius leschenaultii Lesson Collected by Everett and by McGregor. Family SCOLOPACIDAE. Snipe, Sandpipers, etc. Numenius phaeopus variegatus (Scopoli) Collected by McGregor. Numenius madagascariensis (Linnaeus) Collected by McGregor. Limosa lapponica baueri Naumann Collected by Everett and by McGregor. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 327 Tringa totanus eurhinus (Oberholser) Collected by Everett and by McGregor. Tringa nebularia (Gunnerus) Collected by McGregor. Tringa ochropus Linnaeus Collected by McGregor. Tringa glareola Linnaeus Collected previously by Everett. Sandayong, Sierra Bullones, 300-350 meters altitude; 1 9 ; April 2. Wing, 123.5. Culmen from base, 33.5 mm. Weight, 70 grams. This winter visitor was fairly common in the small valleys planted to rice and drained by a small creek with a small area of marsh beside it. Xenus cinereus (Guldenstaedt) Collected by Everett. Actitis hypoleucos (Linnaeus) Collected by Everett. Heteroscelus brevipes (Vieillot) Collected by Everett and by McGregor. Arenaria interpres interpres (Linnaeus) Collected by Everett. Gallinago megala Swinhoe Sandayong, Sierra Bullones, 300-350 meters altitude; 1 9 ; April 14. Wing, 141. Culmen from base, 71 mm. Weight, 149.2 grams. Recorded for the first time from Bohol. This species is easily the most common and widely spread of the three species of snipe that winter in the Philippines. It was often flushed from the marshy, grassy sides of creeks in the cultivated areas, and in the wet rice fields left fallow at the time. Gallinago gallinago gallinago (Linnaeus) Collected by Everett. 328 FIELDIANA: ZOOLOGY, VOLUME 35 Erolia ruficollis (Pallas) Collected by Everett and by McGregor. Limicola falcinellus sibirica Dresser Collected by Everett. Family LARIDAE. Gulls and Terns. Thalasseus bergii cristatus (Stephens) Collected by Everett and by McGregor. Family COLUMBIDAE. Pigeons and Doves. Treron pompadora axillaris (Bonaparte) Cantaub, Sierra Bullones, 700-750 meters altitude; 2 cf , 2 9 ; April 29. Wing, cf 158, 162; 9 160, 162. Culmen, & 23, 23; 9 23, 23.5 mm. Weight, cf 218.3, 244; 9 227.7, 257.1 grams. First record of the species from Bohol. Bohol birds do not differ from specimens from Negros, Siquijor, Samar and Mindanao. In original forest and at the edges the species went in flocks con- taining from six to a dozen members. Treron vernans vernans (Linnaeus) Collected by Everett and by McGregor. Phapitreron leucotis albifrons McGregor Collected previously by Steere Exp. and by McGregor. Luyo-Wahig, Sierra Bullones, 200 meters altitude; 1 nestling; May 16. Sandayong, Sierra Bullones, 300-350 meters altitude; 6 cf , 3 9 ; March 30-April 16. Cantaub, Sierra Bullones, 700-750 meters altitude; 6 cf , 9 9 ; April 7-May 8. Wing, cf (12) 123-133 (av. 127.2); 9 (12) 121-131 (av. 127.5) mm. Culmen, cf (12) 18-20 (av. 19); 9 (12) 18-20 (av. 19) mm. Weight, cf (10) 90-117 (av. 107.8); 9 (12) 103.9-135.6 (av. 114.2) grams. The Bohol specimens do not differ from Samar and Siquijor birds. The species was one of the most common forms on Bohol. It was found in second growth, original forest, and even in well-cultivated areas inside the mixed tree and shrub growths along the hedges. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 329 Many males and females had enlarged gonads in April and May. One nestling a few weeks old was taken on May 16. Phapitreron amethystina amethystina Bonaparte Collected previously by McGregor. Sandayong, Sierra Bullones, 300-350 meters altitude; 1 cf , 1 9 ; April 7-14. Cantaub, Sierra Bullones, 700-750 meters altitude; 9 cf , 6 9 ; April 14-May 4. Mayana, Jagna, 700-750 meters altitude; 1 cf ; May 5. Wing, cf (11) 143-156 (av. 150.5); 9 (7) 140-151 (av. 144.7). Culmen from base, cf (11) 26.5-29 (av. 27.8); 9 (7) 25-28 (av. 26.6) mm. Weight, cf (10) 131-149.4 (av. 141.1); 9 (6) 111.5-144.5 (av. 128.3) grams. Birds from Bohol average slightly darker on the under parts com- pared to Samar birds, but there is a great deal of overlap between the two populations. The Bohol birds were described by Manuel as P. a. celestinoi, which we consider a synonym. Ptilinopus occipitalis Gray Cantaub, Sierra Bullones, 700-750 meters altitude; 4 cf , 3 9 ; April 19-May 7. Wing, cf (4) 151-161 (av. 156); 9 (3) 143.5-159 (av. 151.8). Culmen from base, cf (4) 22-23 (av. 22.5); 9 (3) 22-23 (av. 22.3) mm. Weight, cf (4) 204-260.5 (av. 228.1); 9 (2) 209.4, 223.8 grams. First record of the species from Bohol. Ptilinopus leclancheri leclancheri (Bonaparte) Collected by McGregor. Ducula aenea glaucocauda Manuel Collected by McGregor. Sandayong, Sierra Bullones, 300-350 meters altitude; 2 cf; April 12-May 3. Wing, cf 234, 245. Culmen, cf 33, 33.5 mm. Weight, cf 545.8 grams. The species was rather scarce in the localities in which we col- lected but was reported to be quite common in the lower elevations. The birds were taken in tall trees at the edge of the well-logged rem- nant patch of original forest in an area otherwise grassland and cultivated. 330 FIELDIANA: ZOOLOGY, VOLUME 35 [Ducula tricolor (Scopoli) Included by Worcester and Bourns (1898, p. 551, species no. 29) in the Bohol list but McGregor (1907, p. 318) himself commented that "... this species is given as being found in Bohol but I find no original record of the species from this island and it was not observed by us."] Macropygia phasianella tenuirostris Bonaparte Collected previously by McGregor. Cantaub, Sierra Bullones, 700-750 meters altitude; 3 cT, 1 9 ; April 20-27. Wing, cf (3) 180-184 (av. 182); 9 177. Culmen, d 1 (3) 21-23 (av. 22.3); 9 21.5 mm. Weight, tf (3) 177.4-180.6 (av. 178.7); 9 170 grams. A female bird secured on April 25 had an egg with hard shell in the oviduct ready for laying. Streptopelia bitorquata dusumieri (Temminck) Collected previously by Everett, Steere Exp., and McGregor. Sandayong, Sierra Bullones, 300-350 meters altitude; 2 cf; May 12. Pawaksalan, Sierra Bullones, 300-350 meters altitude; 2 rf, 1 9 ; May 17. Wing, d 1 (4) 160-164 (161.7); 9 160. Culmen, tf (4) 22-22.5 (av. 22.1); 9 23 mm. Weight, d 1 (4) 145.5-173.7 (av. 158.5); 9 158.5 grams. Three males from Bohol show both wing and tail molt in May, and one shows only the wing molt in the same month. The single female had enlarged gonads in May. Chalcophaps indica indica (Linnaeus) Collected previously by McGregor. Luyo-Wahig, Sierra Bullones, 200 meters altitude; 1 cf ; May 16. Sandayong, Sierra Bullones, 300-350 meters altitude; 2 d" 1 , 4 9 ; April 2-May 15. Canlangit, Sierra Bullones, 300-350 meters alti- tude; 1 d 1 ; May 14. Abakhanan, Sierra Bullones, 300-350 meters altitude; 1 9 ; May 17. Wing, d" (4) 145-153 (av. 148); 9 (5) 132-146 (av. 140.8). Cul- men from base, d" (4) 23-24 (av. 23.5); 9 (5) 21.5-23 (av. 22.5) mm. Weight, d 1 (4) 119.5-133.7 (av. 126.5); 9 (4) 108.1-125.5 (av. 118.5) grams. RAND AND RABOR: BIRDS OF PHILIPPINE ISLANDS 331 One male and two females had enlarged gonads in May. One female showed wing molt in May. One young bird just out of the nest was taken on May 12. It must have come from an egg laid in the latter half of March. Family PSITTACIDAE. Parrots, Lories, Cockatoos, etc. "Kakatoe haematuropygia (Mliller) Collected by McGregor. Prioniturus discurus whiteheadi Salomonsen Collected previously by McGregor. Anislagan, Sierra Bullones, 300-350 meters altitude; 1