Classification, distribution, and life 

 history studies 



In addition to providing staff services 

 on nriatters related to the taxonomy, distri- 

 bution, and life history of birds and 

 mammals, maintaining extensive study col- 

 lections, and providing identification serv- 

 ices for cooperators and scientists through- 

 out the courtry, the staff of the Bureau's 

 Bird and Mammal Laboratories located at 

 the U.S. National Museum is engaged in 

 several active research projects. Brief 

 mention is made of some of these. 



Studies of the sea otter in Alaska have 

 been made sporadically since 1936, and 

 more intensively by Branch per sonnel since 

 1955. During 1961, progress was made on 

 analyzing and organizing, with a view to 

 publication, the accumulated information on 

 natural history and behavior, experimental 

 transplanting, populations, pelage, ecology, 

 aging, reproduction, and pathology of this 

 species. 



During March 1961 an aerial survey of the 

 Pacific walrus over parts of the Bering Sea 

 was made with the cooperation of personnel 

 of the Alaska Regional Office and the Alaska 

 Fish and Game Department. This resulted 

 in an estimate of 90,000 walrus in the area 

 surveyed. This was followed by a survey of 

 marine mammals in the Chukchi Sea in the 

 vicinity of Cape Thompson at the request of 

 the Atomic Energy Commission. 



Progress was made, also, in a taxonomic 

 review of the bobcats; on research on the 

 mammals of Maryland, Delaware, and the 

 District of Columbia; and on the mammals 

 of Alaska. Among the bird research projects 

 were studies of the geographic variation 

 in the hermit thrush, the sandhill cranes, 

 and the Canada geese. A color chart using 

 color values from the Munse ll Book of 

 Color was developed to aid in field identifi- 

 cation of Canada geese. 



Through the cooperation of the Juneau 

 Regional Office of the Bureau, critical 

 specimens representing breeding popula- 

 tions of Canada geese in Alaska were ob- 

 tained for the study collection in the Bird 

 and Mammal Laboratories, U.S. National 



Group of walruses resting in close pack ice near an 

 op>en lead, southwest of St. Lawrence Island. Photo- 

 graphed from survey plane by Karl W. Kenyon. There 

 are 182 walruses in this picture. 



Museum. These specimens have enabled 

 Bureau taxonomists to gain a much clearer 

 picture of the distribution of six markedly 

 different appearing populations of Canada 

 geese which nest in Alaska. The character- 

 istics of the endangered Aleutian Island 

 Canada goose were more precisely defined 

 to aid in selecting geese for possible re- 

 stocking of depopulated islands, when breed- 

 ing stock is located. 



Analysis of measurements and weights of 

 sandhill cranes examined at checking sta- 

 tions during the open season on this migra- 

 tory gamebird in eastern New Mexico in 

 January 1961, corroborated results of prev- 

 ious studies by failing to disclose any ex- 

 amples of the relatively rare greater 

 sandhill crane. An examination of specimens 

 of sandhill cranes collected previously in 

 the depredations area of central North 

 Dakota indicated that the intermediate- 

 sized cranes from the Prairie Provinces 

 of Canada together with a few greater 

 sandhills move through that area in early 

 September, followed later by typical 

 Arctic-breeding lesser sandhills which, in 

 1959, reached peak numbers in early 

 October. 



Also, at the Bird and Mammal Labora- 

 tories, coordination and servicing were 



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