Showing papers in "The Auk in 1943"

Notes on the Birds of Southampton Island, Baffin Island and Melville Peninsula

Abstract: 1%TEW ENGLAND MUSEUM OF !XTATURAL HISTORY 1941. Bulletin of New England Bird Life, Jam-June. ROBERTS, THolVlAS S. 1936. Birds of Minnesota, 2: 364-367. (Univ. of Minn. Press.) SUTTON, GI•ORGE m. 1928. Birds of Pymatuning Swamp and Conneaut Lake, Crawford County, Pennsylvania. Ann. Cam. Mus., 18:19-239 (1⁄2f. p. 174). Sv,•N•r, MYRON H. 1929. The Pine Siskin in Nebraska. Wils. Bull., 41: 77-92. TODD, W. E. CLYDE 1940. The Birds of Western Pennsylvania: 614-617. (Univ. of Pitts. Press., Pittsburgh, Penna.) WALKINSHAW, LAWRENCE H. 1939. Life History Studies of the Eastern Goldfinch. Jack Pine Warbler, 17: 19-20.

A Gross Study of the Bursa of Fabricius and Cock Spurs as Age Indicators in the Ring-Necked Pheasant

Abstract: THE accurate establishment of age groups of animals is an important phase of many ecological studies. In experimental management programs whose prime consideration is to measure yearly population trends, the ability to distinguish age classes has a special significance. It is often possible from an analysis of a fall population to make some evaluation of the extent of the previous spring and summer breeding and the subsequent survival of young. In the case of game species, autumn hunting often results in the kill of a large percentage of the total population. Conservation officers' road blockades, managed hunting areas, etc., provide situations which make possible brief examination of significantly large numbers of these animals. Where techniques are available which permit rapid interpretation of various characters and conditions, considerable valuable information is obtainable from these sources. At the Rose Lake Wildlife Experiment Station, Clinton County, Michigan, the Game Division has in progress a long-term study on the management of farm wildlife. On this area, extensive year-round observations culminate in a carefully measured and studied fall harvest of pheasants (Phasianus colchicus torquatus), rabbits (Sylvilagus floridanus mearnsii), and fox squirrels (Sciurus niger rufiventer) from 1500-2000 acres of farmland. The hunting is conducted under a managed plan which requires that all participants keep individual hunting records and submit all game taken to the station laboratory for examination. This system, in effect for two years, has made possible the examination of reasonably large samples of the several game species. As a result of these examinations and certain incidental studies, data have been obtained which have resulted in simplified methods for rapid age determination of pheasants by external means. These techniques utilize spur conditions in males, and the bursa of Fabricius in either sex. The value of the bursa as a means of distinguishing adult from juvenile game birds was first recognized by Gower (1939). The technique as reported depended upon dissection for demonstration. It was consequently not suited to the rapid handling of a large series of dead birds and, of course, was not usable on living birds. As mentioned by Gower, these points constituted the principal limitations.

A Study of the Violet-Green Swallow

Abstract: One of the first new bird acquaintances to intrigue particular interest on my arrival at Puget Sound from the east in 1888 was the pretty little violet-green swallow, Tachycineta thalassina lepida. Its seasonal comings and goings, its ways of daily life have ever since received my watchful attention. For a number of years these swallows have nested beneath the eaves of my sleeping-porch, thus supplying opportunity for an "aroundthe-clock" acquaintance with them. In voluminous notes are recorded the particulars of their nestings, the phenomenal over-growth of the young birds and the recession to rzormal adult weight,* also various factors that promote or retard the processes of nidification. The study involves, perhaps, some implications of bird psychology.

Factors in the Incubation Behavior of the Common Tern

Abstract: Hartert (Nov. Zool., 32: 147, 1925) says: "This peculiar bird is known only from the type specimen. It is very peculiar, the crown to the base of the upper bill nearly black, underside heavily striped. I am not sure about its relationship." Hartert and Steinbacher (V6gel pal. Fauna, Erganzungsband, 4: 374, 1935) says: ". . . das man fur ein melanistiches stuck halten m6chte, doch hebt der Autor den schlankeren und spitzeren Schnabel noch besonders hervor."