ANAKTXTVTJK PASS 



97 



Family TURDIDAE: Thrushes, SoHtaires, Bluebirds 

 Tardus migratorius migratorius Linnaeus 



males 



May 15-Sept. 18 



weight (14), 70-91, 

 average 79 g. 



4 females 



May 24-Sept. 18 



weight (6), 72-94, 

 average 82 g. 



5 yoimg males 



June 21- Aug. 7 







6 young females 



Aug. 7-Sept. 18 







The earliest records for eastern robins are May 13, 1948, May 18, 

 1949, May 11, 1950, May 10, 1951, May 18, 1952, May 19, 1953, and 

 May 25, 1954. Robins appear to go directly upon arrival in spring 

 to nesting places which are mostly in rather large areas of fair-sized 

 ■willow brush, as around Contact Creek and Kangomavik. I have seen 

 nests at many places in the narrow valleys where a few high willows 

 grow and on a rock ledge at the mouth of Napaktualoitch Cave. On 

 the open tundra around Tuluak Lake they are not often seen. 



Around Contact Creek in the spring of 1952, the first arriving rob- 

 ins appeared to act in pairs at once to establish nesting territory, and 

 females were taken within two days of the first male specimens in 

 1951. However, I saw groups of six robins and numerous single birds 

 on the upper Noatak River and at Howard Pass on May 25, 1952, so 

 that I believe that separation of the small migrant bands into pairs 

 occurs about at the time of arrival at the arctic nesting grounds. 



The tabulation of social and family activities observed among robins, 

 below, presents a good chronicle of their summer activities because 

 in the north, as elsewhere, robins are of conspicuous and demonstra- 

 tive behavior : 



May 10-18, 1948-52 



First arrival 



Anaktuvuk 



May 25, 1952 



Groups of six and single 



Upper Noatak River and 





birds 



Howard Pass 



May 28, 1951 



Pair nesting 



Akvalutak 



May 29, 1952 



Nest building 



Contact Creek 



May 30, 1952 



All pairs settled 



Contact Creek 



June 5, 1952 



First egg 



Contact Creek 



June 10, 1952 



First set of 4 eggs com- 

 pleted 



Contact Creek 



June 17, 1951 



2 well-feathered nest- 

 lings 



Napaktualoitch Cave 



June 21, 1951 



Young in first flight 



Contact Creek 



June 22, 1950 



Young male flying 

 weighed 63 g. 



Kangomavik 



July 31, 1950 



Young — 76 and 79 g. 



Kangomavik 



August 



Family groups 





September 



Flocks frequent 



Summit 



Sept. 12, 1950 



Flock of 50 



Summit 



Sept. 18, 1950 



Last flock of 12 



Summit 



