Analysis of a Resident Flock of Starlings

Starlings (Sturnus vulgaris) in tree cavities in Hopewell Borough, New Jersey, appear quite sedentary, but the estimated flock of 500 in an evergreen roost in the Sourland Hills migrate in mid-November.The migrants follow the ancestral western European NE-SW direction (Kessel, 1953; Bordner et al., 1968; Richardson and Haight, 1970).Starlings in North America developed migratory patterns after their introduction into the United States.Recently settled birds in the Pacific Northwest again follow the same pattern in that some are sedentary, some migratory (Johnson, 1974).Davis (1960) urged the study of Starlings to clarify the unsolved problem of the origin of migration.Data on the migration of adult breeding birds are meager.There are yet insufficient data on the age and sex of Starlings at the time of their banding (Johnson, 1974); subsequently little age and sex information has been available on recoveries.In this study banding, color banding, and field sightings were coordinated to observe the population of Hopewell Starlings through their life span, in their own natural colonies.MATERIALS AND METHODS Starlings are "trap inhibitable" (Suthers, 1974), that is, once caught, their aversion to being handled exceeds the attraction of a free meal, and they tend to avoid traps.Large pull-string traps (2' x 1' x 4'), and large openings (4" x 6") to the all-purpose ground trap, baited with suet and bits of bread, eased cautiousness by Starlings, especially when snow was on the ground.Trapping operations began during the last week in December and continued into May."Winter" was considered to be the last week of December to mid-February, and "spring" began in mid-February to include early migrations.Birds were banded with Fish and Wildlife Service aluminum bands and color bands in combinations to indicate year and season.Data were taken on characteristics that may be variable and therefore useful for determining sex and particularly age.Direction of departure was noted.These data were taken again on repeats and returns.Field observations, roost-nest surveys for banded birds, were done with 7 x 35 binoculars.The roost trees were marked on a street map according to house number, and roosting-nesting cavities were diagrammed in community trees.Coding by position of bands on the legs was noted.Behavioral notes were taken.Field hours were matched for the winter roosting and spring nesting census.BANDING RESULTS AND DISCUSSION Table la and b summarize the total birds banded, and the cumulative returns.There were 256 repeats, and 17 recoveries.During the 7th and 35