Chickadees at Adjacent Feeding Sites: The Effects of Food Deprivation

Abstract

ALTHOUGH wintering Black-capped Chickadees (Parus atricapillus) have been studied at feeding sites for some time, our understanding of their winter movements and feeding patterns remains limited and imprecise. The primary purpose of the present study was to examine the effects of depriving each of two adjacent feeding sites successively of all food. Secondly the study tested the conclusions of past research regarding the size and stability of chickadee feeding congregations. Past studies are in agreement that many chickadees remain at a given feeding site for the duration of a winter (Butts 1931, Wallace 1941, Odum 1942). They also find that individuals commonly move from one site to another in the vicinity; three-fourths of a mile is the maximum distance reported. The only previous study of the effects of food deprivation on the movement of a known congregation was conducted by Butts (1931). He found that 11 of 14 chickadees visiting one feeder moved 640 m to another feeder after the original feeding site had been deprived of food for several weeks. The birds did not return to the original feeding site when feeding was resumed, for which a 2-week interruption in feeding at all sites may have been responsible. The results were also complicated by decreased use of feeding sites with the approach of spring.