Behavioral Consequences of Habitat Selection in the Herring Gull

Abstract

Data were collected on time budgets, rates of chick provisioning, and patterns of aggressive behavior in Herring Gulls Larus argentatus that nested in three distinct habitats on Great Island, Newfoundland. Exposed marine terraces (rocky habitat) had the highest nest density, and territories were subject to high levels of intrusion by prospecting conspecifics. This resulted in high levels of aggressive interaction, yet these birds had high breeding success. In contrast, gulls nesting in meadows suffered a high rate of predation on eggs and young. This predation pressure forced male birds to remain on their territories to defend their nests, which resulted in high rates of neighbor-neighbor aggressive interaction, and a reduced rate of chick provisioning by males. The third habitat, grass-hummock covered maritime slopes (puffin habitat) had low nest density and little or no predation pressure. This resulted in low levels of aggressive interaction and reduced vigilance with no apparent decline in offspring production. The results of this study demonstrate how habitat choice can have behavioral consequences that contribute to variation in offspring production within a species.