The Role of Seed Size in Dispersal by a Scatter-hoarding Rodent

A field experiment was conducted in the Nouragues Reserve, an undisturbed lowland rain forest in French Guiana, to test possible selective pressures towards higher seed value of Carapa procera by scatter-hoarders, and to quantify survival probabilities of seeds harvested and cached by red acouchies (Myoprocta exilis). The following hypotheses were also tested: (1) large seeds are more likely to be harvested by acouchies than small seeds; (2) large seeds are harvested by acouchies more quickly than small seeds; (3) large seeds harvested by acouchies have a higher probability than small seeds to be cached rather than eaten; (4) large seeds are cached further away and in lower densities than small seeds; (5) large seeds are recovered from caches and consumed at lower rates than small seeds; and (6) large seeds have higher survival probabilities than small seeds. All seeds were removed within 1.5 days, except for three seeds, which were removed 1-2 days later, thus hypothesis 1 was not confirmed. A total of 362 seeds were located after dispersal wherein 84% was cached and relatively few seeds (16%) were eaten, which confirms hypothesis 3. The distance at which acouchy caches were found immediately after dispersal was highly variable, both within and among plots. The nearest cache was found