Animal Behavior 11e Video 11.2: Siblicide in the cattle egret

Two earlier-hatched, larger offspring of the adult egret competing for food. Note the way the begging chicks grasp the parent's beak in an effort to induce regurgitation. Note also that regurgitated fish bits that fall into the nest are eagerly picked up by the competitors. But the most striking feature of the video is the vicious treatment of the third chick in the nest, which is regularly struck by its siblings and is now so intimidated that it crouches on the bottom of the nest for much of the film. When this unfortunate chick moved about the nest, it was hit again by one of its siblings, with the result that it toppled out of the nest altogether. Young at this stage never make it back to the nest after being ejected.

Transcript Area

Textbook Reference: Family Conflict, p. 411