HORSE RESPONSE TO ENTEROLOBIUM CYCLOCARPUM (LEGUMINOSAE) FRUIT CROP SIZE IN A COSTA RICAN DECIDUOUS FOREST PASTURE

Abstract

When four 400-fruit crops and one 5000-fruit crop of Enterolobium cyclocarpum (Leguminosae) were presented to 17 range horses in the early rainy season in a 10 ha pasture in the deciduous forest lowlands of Pacific coastal Costa Rica (Santa Rosa National Park), they consumed all of the 6600 fruits in about in about eight days. For the first six days of foraging, the horses ate an average of 46 to 71 fruits per day per horse. The horses appeared to prefer to forage in the large fruit crop. The small crops disappeared at quite different rates, apparently owing to small differences in their locations. In their daily movements, the horses made repeated trips between the fruit crops below sparse trees and the more open grazing areas. Fruit consumption rates by the horses and the timing of fruit drop by E. cyclocarpum trees should influence the seed defecation rates of the horses; these rates influence the probability that the seeds in the dung will be found by seed predators.