PINE SISKIN 435 



Data on the growth and development of young siskins have not been 

 published in detail. In New Hampshire, Weaver and West (1943) 

 report that the brood of two young they studied showed their first fear 

 reactions about in their 6th day. The young became very active 

 during the last 4 days of nest life and the female then spent little time 

 brooding them. They took turns exercising and stretching their 

 wings, also walking on the nest rim. In their haste to be fed, they 

 sometimes fell over the side and grasped the outer structure and pulled 

 themselves back again. They say that "The adults seemed to ap- 

 proach the nest rather deliberately during the last 2 days, seemingly 

 coaxing the 3"0ung to such daring feats." 



Both young left the nest 15 days after the first hatched; thus one 

 was a nestling 14 days (it probably departed prematurely) and the 

 other 15, which may be the usual initial flight age. 



One young was seen being fed in the nest tree an hour or so after 

 both had left the nest. Other observers have indicated that the young 

 are with the parents and fed several days, or longer, but the span of 

 time from nest-leaving to independence remains unknown. 



Whether our bird, like the Old World siskin, Spinus spiniis, is 

 double-brooded is still a moot point. There is a strong probability 

 that it is — at least in some years — and that the birds may change 

 localities between nestings. E. H. Forbush (1929), without direct 

 support, says: "One brood yearly, probably two in many cases." 

 Suggestive is a single sentence by William Brewster (1938) relative 

 to the siskin on Aug. 9, 1873, at Lake Umbagog on the Maine-New 

 Hampshire boundary: "A male shot this morning was unmistakably 

 breeding and yet full-grown young are about in considerable numbers." 

 As already shown, the siskin is an early nester; also, fresh eggs are 

 fairly common as late as early June in some localities and seasons, 

 especially Pacific coastal states, and eggs or nestlings in July have 

 been recorded for a number of localities widely spaced geographically. 

 Here are some late breeding records: set of five eggs July 22 in On- 

 tario (Baillie and Harrington, 1937); pair of siskins seen copulating 

 July 30 on Forrester Island, Alaska (WiUett, in Mierow, 1946) ; nest 

 with young August 4 in Faith Valley, Calif. (Bassett, in Mierow, 1946) 

 birds in breeding condition carrying nesting material, July 15- 

 August 14, in the Porcupine Mountains, Mich. (W. B. Barrows, 1912) 

 four young left the nest August 19 at Bozeman, Mont. (A. A. Saunders 

 1921); clutch of three fresh eggs August 14 at Tacoma, Wash. (C. W 

 Bowles, 1903); and nests "containing young in early September,' 

 also at Tacoma (J. H. Bowles, 1924). Omitted are various late dates 

 for adults reported as seen "feeding young"; it is assumed they are 

 for young that have been flying, and for an unknown length of time. 



646-737— 68— pt. 1 30 



