Digestive Seed Predation by a Costa Rican Baird's Tapir

Abstract

The large ungerminated seeds of guanacaste (Enterolobium cyclocarpum) and cacao trees (Cassia grandis) , and plastic buttons, were fed to a captive adult male Costa Rican Baird's tapir (Tapirus bairdi) in artificial fruits, Seed survival during gastrointestinal passage and seed passage rate was studied. The tapir's digestive processes killed 78 percent of the guanacaste seeds and all of the carao seeds, despite their hard seed coats, apparently because they germinated and thereby become suspectible to digestive fluids. Guanacaste seeds that sUlvived required an average of 15.3 days to make the trip through the tapir; the dead carao seeds required an average of 10.3 days and the two sizes of buttons required an average of 8.1 days (730 mg) and 10.3 days (360 mg) to make the passage. The tapir is clearly a seed predator of guanacaste seeds as well as a potential dispersal agent. Which of these functions is more important depends on the unknown behavioral interaction between the tree and the tapir.