Adults and young do not always escape by flying; on July 20, 1951, we were enroute from the landing lake to Kaolak when an adult male and female with eight young ran 200 feet down established tracks of a weasel vehicle. It was necessary to reduce the speed of the vehicle to spare the young. A male at Kaolak River (July 12, 1951) ran 150 feet under the protection of willows to an opening where it remained until flushed. It flew 50 feet, then alighted in another patch of willows.
At Gavia Lake at 11:30 P.M. a ptarmigan called because one of its young was caught in a trap at the edge of a lake. The juvenal bird, unharmed, was released and inadvertently was dropped into the water where it floated but finally, becoming confused, got its head and bill under water and drowned.
On July 15, 1951, at 11:00 P.M. at Kaolak River, we heard a ptarmigan joining an Arctic tern and several sandpipers in protest to a passing red fox.
For three consecutive days a family (male, female and young) at Topagaruk was within 50 feet of one place.
The following measurements of juveniles show increase in size as correlated with advance of season: Topagaruk (July 6, 1951) two juveniles averaging 110 mm in length weighed 21 grams; Kaolak River (July 17, 1951) young of one family averaged 178 mm in length and another individual was 162 mm in length and weighed 38 grams; Kaolak (July 21-27, 1951) individuals in a group of nine [were] approximately ¾ the size of parents and other groups were 1⁄3 to 2⁄3 the size of adults.
In a brooding female 600 mm long from Topagaruk (July 8, 1951) the largest ovum was two mm in diameter. Females, averaging 650 mm long from Kaolak (July 23, 1951) had ovaries smaller than the normal size for breeding birds; the largest ovum was only ½ mm in diameter. Males of the same size had testes six mm in length.
Lagopus mutus nelsoni Stejneger: Rock ptarmigan.—Specimen, 1: Wahoo Lake, 146°58', 69°08', 2350 ft., No. 31309, ad. male, July 11, 1952.
At Wahoo Lake (July 6, 1952), young of one brood for the first time since July 3, called continually throughout the day and part of the night. Members of three other broods, only a few days old, did not call in the same persistent way.
Along a deeply eroded western outlet of Wahoo Lake there was an unusual concentration of fecal droppings, spaced approximately every two or three feet. This sheltered place offered protection from cold and winds of winter. Adults were associated with willows along creeks and on adjoining sidehills where willows gave way to open tundra. One family left the willows and the female flew back and forth behind the young as she herded them. The largest adult male seen here was shot on July 11. It was 365 mm in total length, weighed 460 grams, and had testes 7 mm long.
At the south end of Lake Peters (August 14, 1952), a female and her two young, along with other kinds of birds, were attracted to our tent during snowstorms. On July 18 at Wahoo Lake, a juvenile was 200 mm in total length and weighed 100 grams whereas on August 9 at Lake Peters a juvenal male was 261 mm in length and 226 grams in weight.