Abstract

In this research, we studied escape and nest defence reactions to a human intruder presence in "Larus cachinnans" Pallas, 1811. In this study, we observed the birds in an uninhabited environment, while our previous studies were set in a highly anthropized environment (Conte 1999, Conte 2000). Each of the six selected subjects (from different nests) was approached by a human intruder six times in two separate occasions: 25 days after egglaying and 3-5-days after hatching). The behaviours observed were alarm, escape from the nest, fly, landing, and return to the nest. During incubation all the animals showed the same behaviour. Aggression and nest defence increased during the hatching period. Aggression and nest defence behaviours increased proportionally to the intruder's pupil dimension.