Observations on the behavior of rain forest peccaries in Peru: Why do white-lipped peccaries form herds?
Zeitschrift für Tierpsychologie
1983
Journal Article
62
3
241-255
Parque Nacional del Manu Plants Vascular plants Spermatophytes Angiosperms Dicots Animals Chordates Vertebrates Mammals Artiodactyls Carnivores Cocha Cashu Tayassu pecari Tayassu tajacu animal behavior small spatial scales feeding ecology predation Madre de Dios Bibliography
The ecology and behavior of Tayassu tajacu and T. pecari were studied for 16 mo. in the years 1975-1978 in the Manu National Park in southeastern Peru. From 132 sightings of T. tajacu at the study site, and from reports from other regions, groups of this species in rain forest usually contain fewer than 12 individuals. T. tajacu repeatedly used wallows in the forest. Individuals of this species were relatively sedentary. Herds of T. pecari were encountered on 60 occasions. Five counts indicated that there were over 100 individuals in the herds. This species was encountered at practically random intervals, more frequently in the dry season than in the rainy season. Adults of both species are prey primarily of large cats and humans. Both species feed on green plant parts, fruits, nuts and seeds, but T. pecari feeds on more resistant seeds and nuts than T. tajacu. The hardest palm nuts that only T. pecari can consume are distributed in a patchy manner. Cracking these nuts between the teeth causes the animals to be heard more than 50 m away. The patchy distribution of the hard nuts and seeds prevent T. pecari from being sedentary. Group formation has several individuals benefits for foraging efficiency and defense against predators; avoidance of searching for food in places recently visited by others, benefiting from the knowledge of experienced foragers, reducing the per capita probability of detection by predators, reducing the probability of being captured after group detection by predators, increasing the ability to counterattack as a group, increasing the probability of detecting the predator before it can attack and confusing the predator through escape behavior. T. tajacu seems to live in small groups because its typical foods are distributed more evenly and because consumption of these foods does not cause individuals to be so noticeable to predators.