When top-down becomes bottom up: behaviour of hyperdense howler monkeys (Alouatta seniculus) trapped on a 0.6 ha island.
Predators are a ubiquitous presence in most natural environments.Opportunities to contrast the behaviour of a species in the presence and absence of predators are thus rare.Here we report on the behaviour of howler monkey groups living under radically different conditions on two land-bridge islands in Lago Guri, Venezuela.One group of 6 adults inha