The feeding ecology of translocated howler monkeys, Alouatta pigra, in Belize

Scott Charles Silver, Fordham University


The feeding ecology of translocated black howler monkeys (Alouatta pigra) was studied in Belize, Central America. Data collection began in March 1994, in the Community Baboon Sanctuary (CBS), in northern Belize. In May 1994, two troops were translocated to the Cockscomb Basin Wildlife Sanctuary (CBWS), in southern Belize and studied for 12 months. Two troops translocated previously into CBWS and two troops remaining in CBS were also studied. Activity and diet composition of all study troops are presented. Monkeys in CBS spent an average 24.4% of their time feeding, 61.9% resting, and 9.8% traveling. Diet composition was similar to other Alouatta species, with 41% of feeding time spent eating fruit, 45% foliage, and 11% flowers. Alouatta pigra was selective in its dietary choices, and adjusted its diet to changing abundance of food items. Troops in CBWS spent less time feeding overall, and less time eating fruits than troops in CBS. Despite low vegetative overlap between the two sites (32%), translocated troops appeared to experience little difficulty incorporating novel foods into their diet. Analysis of dietary overlap between troops indicates a brief period of diet adjustment may initially have occurred upon translocation, and re-occurred with seasonal changes in the distribution of food resources. Recently translocated troops had higher dietary diversity, ate fewer mature leaves, fed from fewer trees, and may have remained at fruiting trees longer than established troops. Phytochemical analysis of plant parts indicates that monkeys in CBWS had less access to water-soluble carbohydrates than monkeys in CBS, and may have relied on mature leaves to provide supplemental sugars. These analyses revealed few differences between the diets of troops in CBWS. Levels of condensed tannins, total phenolics and alkaloid content in foliage samples suggest their presence did not preclude the inclusion of these items in the howler diet. Monthly variations in activity indicate A. pigra increases resting in response to reduced feeding time, with little variation in time spent traveling. This combined with an ability to adjust the relative time spent eating fruits and foliage as food abundance fluctuates, may make howler monkeys particularly suited to translocation.

Subject Area

Ecology|Behaviorial sciences|Zoology

Recommended Citation

Silver, Scott Charles, "The feeding ecology of translocated howler monkeys, Alouatta pigra, in Belize" (1998). ETD Collection for Fordham University. AAI9816361.