Seed Dispersal Ecology of a Wind Dispersed Rain Forest Tree in the Western Ghats, India

Abstract

Fecundity and seed dispersal of Lophopetalum wightianum, Wight (Celastraceae), a wind dispersed canopy tree species, were studied in the rain forests of the Western Ghats, India. The effects of fruit crop size, seed characteristics, tree height, and wind speed on seedfall and dispersal distances were investigated. Fruiting was synchronous and fruits were produced between February and April. Smaller fruits suffered more predispersal predation. The majority of seeds, described as rolling autogyros were dispersed near the parent. The rate of descent of seeds was related to the square root of wing-loading. However, wind speed significantly decreased the rate of descent and increased dispersal distances. Taller trees dispersed seeds more evenly. Large trees had a significant dispersal advantage since they were more fecund and dispersed seeds further away and more evenly, thereby decreasing the probability of mortality due to density and distance dependent predation. These results show that there is convergence in dispersal strategies of Lophopetalum wightianum with wind dispersed trees studied in the neotropics.