EFFECT OF BIRD DENSITY ON THE DECISION TO JOIN A GROUP INTHE SICALIS FLAVEOLA PELZENI (PASSERIFORMES, EMBERIZIDae)

A change in bird density within a captive flock of Sicalis flaveola pelzeni (Sclater, 1872) affected thedecision to join a group. Ruling out inter-individual differences and maintaining constant the size of a foodpatch, birds were found to fly more often to the food source and spend a longer time in its environs when keptin greater groups.

Celia M. Lombardi and Marcela Charbuki, Iheringia, Ser. Zool., Porto Alegre, (92):105-109