Data from: seed dispersal by frugivores without seed swallowing: evaluating the contributions of stomatochoric seed dispersers

The process of seed dispersal that underpins ecosystem maintenance is
performed by diverse arrays of fruit-eating animals. However, seed
dispersal studies are primarily focused on a subset of these animal
communities that disperse seeds by endozoochory. Stomatochory (seed
dispersal in which seeds are carried externally and are not swallowed) is
rarely considered to be effective, despite an increasing number of
taxa-focused studies that indicate otherwise. We collated the available
information on stomatochory to provide a quantitative overview of the
dispersal mechanism, including plant-types and fruit-traits dispersed,
dispersal distances and germination potential for all available taxa. We
compared seed sizes dispersed, dispersal distances, and germination
potential with corresponding data on endozoochory for bats and primates.
We also identified the main taxa dispersing seeds by stomatochory and
assessed what factors influenced the distances that they carried seeds to.
Stomatochoric dispersers can displace large quantities of seeds, including
large seeds and those of large fruits, and over short to long distances
(> 1 km). Compared to similar-sized endozoochoric dispersers, they
can disperse larger seeds, but over shorter distances, on average. Similar
to endozoochory, seed handling by stomatochory also improves the
germination potential of dispersed seeds. Dispersal distances achieved by
stomatochory were influenced by body mass, daily path length, seed width,
fruit type and seed handling techniques. Five main taxonomic groups of
stomatochoric dispersers were identified: bats, parrots, squirrels,
corvids and Old World monkeys (cercopithecines). Parrots perform dispersal
services for the largest fruits and over the longest distances. However,
given the lack of research on stomatochory, it is likely other taxa are
also important stomatochoric dispersers but have not been identified yet.
More research attention must be directed towards seed dispersal services
that are not provided by endozoochory. Many stomatochoric dispersers are
common animals within communities and could be playing dominant seed
dispersal roles, even without swallowing seeds. Community-wide studies
should incorporate all seed dispersal interactions, rather than focusing
solely on endozoochory. This will ensure a more robust understanding of
community-wide patterns.