14 T Hite A-U 2D 3B BeOANs—-B Bal Weiaies 
Book Review 
THE RED CROSSBILLS OF COLORADO, by Alfred M. Bailey, Robert J. Niedrach 
and A. Lang Baily; “Museum Pictorial No. 9,” published by the Denver 
Museum of Natural History, Denver, 1953; 64 pages, 27 illustrations, $1.00 
postpaid. 
This is the ninth booklet in the series being published by the Denver 
Museum. It describes and illustrates the nesting habits and life history of 
one of our most unusual Western birds. Red crossbills (Lowxia curvirostra) 
are erratic in behavior, rarely nesting in the same area two years in 
succession. The greater part of the booklet, and all of the photographs, are 
based upon the nesting concentrations which occurred in Colorado in 
1947-48 and again in 1952-58. 
The booklet is divided into two sections. Part One begins with excerpts 
from the monograph on “New World Crossbills,” originally published in 
1937 by Ludlow Griscom_and now out of print. Of the eight races of cross- 
bills defined by Griscom five have been recorded in Colorado, but of these, 
only the Bent’s crossbill has been known to breed there. After a thorough 
analysis of subspecific types, the authors summarize the surprisingly rare 
records of nesting crossbills in Colorado from 1887 to 1947. Then comes a 
detailed account of the 1947-48 influx of Bent’s crossbills, during which 
intensive nesting observations were made, nests being found in ten months 
of the year. 
Part Two describes the “1952 Observations of Red Crossbills,” in which 
nesting took place throughout the year. The findings are summarized under 
such headings as: Flock Behavior, Plumage, Feeding Habits, Song, Ter- 
ritorialism, Nest Building, and so on. There are amusing narratives of 
some of the difficulties encountered in making the observations, and in- 
formation is given on the photographic techniques used. The book con- 
cludes with a four-page bibliography. 
Probably the most interesting parts of the booklet are the excerpts from 
the field notes. In some instances the authors had to follow the first snow- 
plows up winding mountain roads, then haul ladders and equipment over 
the snowdrifts through the dense pine forests. Having brushed the snow 
away from the nests, the scientists would perch with their cameras and 
strobe flash equipment on the swaying ladders for long intervals while 
the crossbills calmly went about their business of feeding the young. The 
results of this research, as evidenced by the pictures, can only be described 
as outstanding. The 27 photographs are of the highest quality, both tech- 
nically and pictorially, and are beautifully printed. 
Dr. Alfred Bailey will probably be remembered by older members of 
the Illinois Audubon Society as a former member of the staff of the Field 
Museum in Chicago. He is a life member of the I. A. S., and is the author 
or co-author of six of the nine booklets in the Denver Museum series. The 
first of his pamphlets, “Nature Photography with Miniature Cameras,” 
stands out in the writer’s memory as one of the most helpful and in- 
formative booklets he has ever read on this exciting hobby. Members who 
