The effect of size and density on nut removal in Syagrus loefgrenii Glassman (Arecaceae) in the Brazilian Cerrado

Efeito do tamanho e densidade sobre a remoção de sementes em Syagrus loefgrenii Glassman (Arecaceae) no Cerrado brasileiro

Abstract

In this study I tested the effect of Syagrus loefgrenii nut size and number on the intensity of removal by rodents across seasons. Trials were performed in which piles of either small or large endocarps (1, 3, 6, 12, and 25) were subjected to removal by rodents in the Cerrado (Brazilian savanna). Despite of variations in the intensity of removal, always this process decrease conform endocarp number. Also, mean proportion of endocarp removal was unrelated to year period, initial number, and size of endocarps. Hence, endocarp removal was consistently negative density-dependent. As, in principle, the observed patterns of nut removal point out similar survival chances for both nut sizes, the pervasive negative density-dependent response emerges as a strategy in S. loefgrenii to swamp rodents all year round irrespective of seed size.

Keywords:
seed predation; density-dependence; plant-animal interaction; palm fruits; Brazil; Cerrado palm