干旱区生态环境知识资源中心

The fruiting phenology and avian consumer set of cardon cactus (Stenocereus griseus) fruits were observed on the semiarid Macanao Peninsula of Margarita Island, Venezuela. The cardon population had two peak fruiting seasons (late May-early June and late August-early September) which correspond to the local rainy seasons, bur many plants also produce low numbers of fruits throughout the year. Fruits were fed on continuously by a variety of consumers for several days while still attached to the plant. The avian consumer set included 14 species and was dominated by two species of parrots (Aratinga pertinax and the endangered Amazona barbadensis), Most of the avian consumers are omnivores that include variable amounts of fruit in their diet. Feeding observations in the wild, captive feeding trials, and seed germination trials indicated that six of the bird species are seed predators, six act as seed dispersers, and two are neutral with respect to seed survival. Bats fed on the fruits but were unable to open the husks, and thus must rely on naturally dehisced fruits or fruits opened by psittacines.