NATURAL HISTORY OF THE MONK PARAKEET IN HYDE PARK, CHICAGO

摘要

We studied Monk Parakeets (Myiopsitta monachus) in Hyde Park, a residential community in Chicago, Illinois. In April 1992, 64 birds were counted at 26 nests in trees, on utility poles, and on an antenna tower. The population increased to 143 birds in July after nestlings fledged. The following spring, 95 birds were still present at the beginning of the breeding season. Both regionally and locally, the dispersion of nests was clumped. Nesting structures contained one to seven active chambers. The parakeets usually foraged in groups of two to 55 birds on plant buds, weeds, and fruits and berries of ornamental shrubs and tress. During the coldest months of the year, December to February, the birds fed almost exclusively on bird seed at backyard feeders. The generality of the Monk Parakeet's diet, their ability to adapt to a variety of habitats, and their apparent great potential for rapid population growth suggest that they will continue their range expansion and population increase in the United States.