Data from: Seed traits, not density or distance from parent, determine seed predation and establishment in an Afrotropical forest

Seed predators drive patterns in seed mortality and seedling establishment
and are posited to contribute to the maintenance of plant species
diversity through several mechanisms. Negative density dependence and
spatially-restricted recruitment are apparently widespread in Neotropical
forests, but are little studied in Afrotropical forests, where generalist
vertebrates may contribute more to seed mortality than do specialized
invertebrates and fungi. We experimentally assessed the roles of seed
density and distance from the parent tree for ten tree species in a forest
in northeastern Gabon, using exclosures to isolate the effects of
different seed predator types. Vertebrates caused greater seed losses than
all other mortality agents combined. Unexpectedly, seeds under fruiting
conspecific trees had significantly lower removal and higher seedling
establishment than those under heterospecific trees or in neutral
non-fruiting locations. Seed density did not significantly affect seedling
establishment. Vertebrate seed removal ranged from 0% to 100% among focal
species, and was positively correlated with seed mass but had no
relationship with species commonness (adult tree density). Seed traits
strongly affected patterns of seed removal and seedling establishment, and
may contribute more to the likelihood of success for an individual seed
than do its density or distance from parent. Our results highlight an
apparent divergence in patterns of seed mortality and seedling
establishment between tropical forest regions, and emphasize the need for
further comparative study.