Data from: Diversity of seeds captured by interception exceeds diversity of seeds deposited in traps

Seed dispersal, a key process in terrestrial landscapes, is increasingly
important in the face of habitat fragmentation and global climate change.
Seed dispersal is also notoriously difficult to characterize, especially
in species rich and spatially complex tropical forests. We contrasted
assemblages of biotically dispersed seeds collected from four sites using
two methods: deposition into seed traps and interception by the capture of
frugivorous birds. We also compared seed deposition and interception with
local fruit production. Species accumulation curves for seeds deposited in
seed traps began to level off sooner than curves for seeds collected from
birds captured in mist nets, and extrapolation showed significantly
greater estimated species richness for seeds collected from birds than for
those deposited in traps. Assemblages from birds and from traps at each
site were quite different, with an abundance-based similarity index of
0.64; this dissimilarity increases if bat-dispersed seeds are included in
the analysis. Common bird-dispersed species were retrieved from both
mist-netted birds and from seed traps, but numerous locally fruiting
understory species were recovered only from birds. We conclude that the
sampling of seeds carried by birds provides a valuable complement to other
methods of studying seed dispersal in species-rich tropical forests by
revealing relationships between specific dispersers and their seed plants
and by creating a more complete account of species diversity of seeds
being transported at a given site.