My own opportunity to study the bird life of Micronesia came as a member
of the scientific staff of the Laboratory of Mammalogy of United States
Naval Medical Research Unit No. 2 (NAMRU2) in the late war. The primary
duty of this laboratory was to obtain examples of the vertebrate fauna
for examination for ectoparasites by the Laboratory of Acarology and to
preserve specimens for identification. As a result sizeable collections
of mammals, birds, and other vertebrates were obtained. In addition,
ecological data were obtained (as time permitted), especially as an aid
in studying the distribution of ectoparasites which affected man. In
1945, I spent eleven months in Micronesia; for most of this time I was
stationed at Guam, the headquarters of the Unit, although one month was
spent in the Palau Islands, two weeks were spent at Ulithi Atoll, and
short stop-overs were made at Eniwetok and Kwajalein atolls. Other
members of the laboratory staff visited Rota and Truk islands.
Subsequent to the field studies in the Pacific, I was sent to Washington
and spent approximately eight months at the United States National
Museum studying the collections of birds and preparing several reports
for publication. In this period other material was studied, both in the
United States National Museum and at the American Museum of Natural
History, New York, and the literature dealing with the birds of
Micronesia was explored and a bibliography of Micronesian birds was
prepared. At the University of Kansas, I continued the bibliographic
work, borrowed and studied some specimens, and completed accounts of the
avifauna of Micronesia.
Under the account of each bird, all known references in the literature,
which mention the scientific name of the bird and its distribution in
Micronesia, are listed. The references are arranged as follows: (1)
citation to the original description, and (2) citations to names in
literature in the order of their first appearance. When a name is a pure
synonym, it may be recognized as such by the fact that the type locality
is given immediately following the citation. In compiling these
references the writer made use of the invaluable work by Wiglesworth
(1891) and of Utinomi's "Bibliographica Micronesia," made available
through the translation by Fisher (1947). The arrangement of the
families follows that of Peters (1931-1945) and Wetmore (1940).
Specimens examined are designated as to collection in which catalogued
by the following abbreviations: USNM, the United States National Museum;
AMNH, the American Museum of Natural History; MCZ, the Museum of
Comparative Zoölogy; and KMNH, the University of Kansas Museum of
Natural History. Average and extreme measurements of specimens are
usually listed in tables; unless otherwise indicated, measurements are
in millimeters, and are of adult specimens. The wings have been measured
by flattening them on a ruler. Weights are in grams. Unless otherwise
indicated, descriptions of the birds have been written by the author.
Descriptions of shore birds are not given; for these the reader may
refer to Mayr (1945a:28-47) where characters useful for identification
of the birds in the field also are given. The writer is especially
indebted to Dr. Ernst Mayr for making available the descriptions of
Micronesian birds made by Miss Cardine Bogert, especially those dealing
with color of the irides, feet, and bill. Color terms in quotation marks
refer to those in Ridgway (1912).
In dealing with insular forms the criterion of intergradation as
indicative of subspecies cannot be applied as it can in kinds of birds
on the mainland which have geographically continuous distributions.
Instead, degree of difference in combination with geographic position
plus other factors such as degree of variation in the geographic races
of the same species or a related species on continental areas are used
in deciding whether two closely related kinds are subspecies or full
species. Many kinds of birds in the islands are modified but little from
island to island (examples, _Rhipidura rufifrons_, _Aplonis opacus_,
_Ducula oceanica_, and _Myzomela cardinalis_), and can be treated as
subspecies. Others show much variability from island to island and it is
uncertain whether they should be treated as subspecies or as separate
species (examples, _Myiagra oceanica_, _Zosterops cinerea_, _Rukia_, and
possibly _Acrocephalus luscinia_). Decisions on generic status are
equally difficult to make. In many cases the experience and judgment of
the taxonomist may be the only criteria by which he can decide whether a
bird is different enough to be considered as a distinct genus. This
"human element" has caused some disagreement. Knowing whether the bird
is to be considered as a distinct genus or instead merely as a species
may not be as important as knowing its correct phylogenetic
relationship. The circumstance that variation in these insular birds is
in general less predictable than in mainland birds adds, I think, to the
pleasure inherent in the classification of the variations.
First, I thank Commodore Thomas N. Rivers (MC) USNR, then commanding
officer of NAMRU2, for the opportunity to join the Unit, for his
interested cooperation in seeing that the plans for field trips were
successful, and for his thoughtfulness in obtaining for me the orders
for duty at the United States National Museum subsequent to our field
investigations. Greatly appreciated also is the help rendered by my
former colleagues of NAMRU2, including Dr. David H. Johnson, Dr. George
W. Wharton, Dr. Aaron B. Hardcastle, Mr. Odis A. Muennik, Mr. L. P.
McElroy, Mr. Charles O. Davison, Mr. Merle H. Markley, Mr. Walter L.
Necker, Dr. Wilbur G. Downs, Dr. Bernard V. Travis, and Mr. E. W.
Coleman. Other personnel, then stationed in Micronesia, who contributed
data used in this report include: Dr. Joe T. Marshall, Jr., (who
generously loaned some of the specimens taken by him in Micronesia),
Dr. C. K. Dorsey, Dr. George Hensel, Mr. Tom Murray, Dr. Irwin O. Buss,
Mr. James O. Stevenson, Dr. Wilfred D. Crabb, Mr. Herbert Wallace, and
Dr. M. Dale Arvey. Authorities of the United States National Museum
provided generously for using the collections there, and I am especially
grateful to Dr. Alexander Wetmore, Dr. Herbert Friedman, and Mr. Herbert
G. Deignan for their cooperation and assistance. Doctor Wetmore kindly
made available many of the birds collected at Bikini during the atomic
bomb experiments. Dr. Robert Cushman Murphy, Dr. Ernst Mayr, and Dr.
Dean Amadon of the American Museum of Natural History made available the
collections in their charge. Doctor Murphy allowed me to examine some of
the heretofore unstudied collections of sea birds of the Whitney South
Sea Expedition. Doctor Mayr generously helped me with taxonomic and
evolutionary problems and made available to me some of his own
unpublished taxonomic notes, the unpublished field accounts of Mr.
William F. Coultas and a partly completed manuscript on the birds of
Micronesia by Miss Cardine Bogert. Mr. James L. Peters generously loaned
specimens from the Museum of Comparative Zoölogy. The use of unpublished
field notes made by Mr. Larry P. Richards at Ponapé and Truk in 1947 and
1948 is also gratefully acknowledged. I am grateful also to my
colleagues at the Museum of Natural History of the University of Kansas
and would single out for special mention Dr. E. Raymond Hall who gave
critical assistance with the manuscript, Drs. Edward H. Taylor and
Herbert B. Hungerford who made helpful suggestions, and Mrs. Virginia
Cassell Unruh who drew the distributional maps.