134 U. S. NATIONAL MUSEUM BULLETIN 217 



nest at Old Crow where the Porcupine River extends the Yukon 

 Valley almost to the Mackenzie River the normal range of both 

 reaches just north of the arctic circle over the full extent of the 

 Brooks Range. 



Family ANATIDAE: Swans, Geese, Ducks 

 Branta canadensis taverneri Delacour 



Sheldon obtained a male specimen from a pair of Canada geese on 

 May 19, 1954, at Kobuk. It conforms with six specimens obtained in 

 migration at Anaktuvuk and with six specimens of these geese from 

 families raised on the Koyukuk and Alatna Rivers for which Herbert 

 Friedmann confirmed my identification as taverneri according to a 

 description by Delacour and Zimmer ( 1951 ) . The testes of the Kobuk 

 specimen were 37 mm. long, greater than in three geese measured dur- 

 ing migration at Anaktuvuk. It was near breeding condition and may 

 represent the numerous Canada geese which nest along the wooded 

 Kobuk in the western interior of arctic Alaska. Grinnell (1900) re- 

 ported hutchinsii, the conmion nesting goose on the wooded Kobuk. 

 Townsend (1887) also reported minima and McLenegan (1889) 

 leuGopacia. Since their specimens are not available these earlier iden- 

 tifications cannot be reliably related to the current nomenclature and 

 we cannot say whether other races than taverneri occur there. 



Branta nigricans (Lawrence) 



As Grinnell (1900) observed, numerous large flocks of brant migrate 

 through the Kobuk Valley late in May but are not seen returning in 

 autumn. Often the migrants fly over the Valley in a northeasterly 

 direction at 4,000 or 5,000 feet, which would clear the adjacent moun- 

 tains, but farther east I have watched and heard them clearing some 

 of the highest peaks in northbound flights at elevations estimated to 

 be over 8,000 feet. No specimens have yet been obtained from Kobuk 

 but at Anaktuvuk nigricans has been identified. 



Philacte canagica (Sewastianov) 



Sheldon found an emaciated emperor goose near Kobuk in 1954. It 

 is known at Kobuk to be a coastal species which rarely straggles inland 

 and it is therefore not numbered in the regular avifauna of Kobuk. 



Anser albifrons (Scopoli) 



White-fronted geese appear about mid-May at Kobuk. Sheldon 

 said that some flocks disappear northward and I have seen them in 

 northward migration over Howard Pass. A large number remain in 

 the Kobuk Valley in summer but move out in August before the Can- 

 ada geese, some of which remain into September. 



