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Correlates of nest-defense behavior of common terns

January 1, 1988

Nest-defense behavior was studied at seven Common Tern (Sterna hirundo) colonies in southern coastal New Jersey during June and July 1981. Data were collected weekly on numbers of adults, nests, eggs, and young in relation to the frequency and intensity of dive attacks on a human intruder by nesting terns. I explored the relationships between attack behavior and colony size/density, seasonality, and brood survival. The results provide little support for social facilitation since neither colony size (range 30-250 nests) nor density was related to mean attack frequency; however, in larger colonies, fewer birds participated in dive attacks. Although the intensity of attacks was strongly seasonal, patterns were very different among colonies and peak attack rates did not always coincide with peak hatching periods. Defense levels declined late in the season in most colonies regardless of whether brood survival was high or low. Colonies with individuals that attacked early in the season had higher overall nesting success than in colonies where individuals showed little early season aggression.

Publication Year 1988
Title Correlates of nest-defense behavior of common terns
Authors R.M. Erwin
Publication Type Article
Publication Subtype Journal Article
Series Title Journal of Field Ornithology
Index ID 5220776
Record Source USGS Publications Warehouse
USGS Organization Patuxent Wildlife Research Center