PINE SISKIN 427 



intently watching the enemy, would literally "freeze" to the spot where he was 

 sitting, hardly moving a feather until the enemy had disappeared. On more 

 than one occasion I have had them "freeze" on my hand, where they had been 

 sitting when the danger threatened. 



Aggressiveness is a marked siskin trait at feeding stations. Davis 

 (1926) placed food on a shelf 3 feet square and found that "the bird 

 that first reached the place seemed to consider himself the sole owner 

 of the entire stand, and woe to the individual that dared dispute his 

 claim." When feeding with purple finches the siskins are bold and 

 usually hold their own. Generally they feed together peaceably, 

 but now and again a siskin takes the offensive and darts at a purple 

 finch, scaring it away. Perhaps the siskin's sharp bill gives it au- 

 thority. In feeding with evening grosbeaks, the siskins keep their 

 distance and show pugnaciousness only among themselves. 



Territory. — Siskins go in flocks containing a few to well over a 

 thousand individuals. Flocks of 50 to 200 are common. 



At the close of the breeding season — usually early summer — the 

 birds generally leave the breeding localities, although the extent and 

 often direction of this movement is unknown. Then the birds may 

 occur in or pass through the nesting area again in autumn. Large- 

 scale incursions in the postbreeding period have not been noted as 

 frequently as autumn and winter invasions. However, in Alberta 

 beginning in mid-June and lasting into August, 1921, large numbers 

 of siskins moved into the park country of the prairie where no ever- 

 greens occur except for small patches along river bottoms. F. L. 

 Farley (1921) reports that at almost any hour of day one could see 

 large flocks, "whirling here and there" in redpoll fashion. They 

 would feed, then take flight suddenly. 



In parts of the siskin's range near and along the Pacific coast, the 

 species occurs in many localities aU year, but a goodly share of the 

 population moves altitudinally to the lowlands in autumn and to 

 higher elevations to breed in spring. The highest altitudinal record 

 is for a siskin that Taylor and Shaw (1927) found dead at approxi- 

 mately 11,000 feet on Mount Ranier, Wash. 



The siskin's center of abundance is from the Rocky Mountains 

 westward. Part of the population in the interior of the continent 

 shows a more or less northwest-southeast movement in autumn and 

 the reverse in spring. Thus it seems likely that the species may have 

 spread eastward, as the evening grosbeak did at a later period, but 

 before the event could be chronicled. M. H. Swenk (1929) wrote: 



Judging from the fact that in various falls that they have occurred in Nebraska 

 the Pine Siskins usually have been seen first in the more westerly and northerly 

 parts of the state, and later in the more southeastern localities, and also from the 

 further fact that they may reach western or central Nebraska commonly in seasons 

 when they are uncommon or absent in extreme southeastern Nebraska, it is 



