Operant Performance at a Feeding Station in Rural Pennsylvania

Abstract

Frequencies of operant responses for food, feeding bouts, and pecks at a food hopper were recorded in three successive winters at a rural feeding station for a mixed-species flock of wild passerine birds. Only one species in each winter performed the operant response, while nine other species did not work for the food they took, and thus benefited from the efforts of the altruists.