Abstract:
Context Both plant size and distribution of plants
and resources across landscapes are known to infuence pollinator behavior and resulting plant reproductive success. However, the relative infuence of these
intrinsic and extrinsic factors is unknown.
Objectives We evaluated the relative contribution of
individual plant size and landscape variables to reproductive success in bat-pollinated baobabs (Adansonia digitata) and determined if the interaction is
scale-dependent.
Methods We recorded fruit number per baobab of
741 baobab in south-central Kenya and measured
size metrics of individuals. We georeferenced baobabs and relevant resources across 10 km2
to generate landscape variables. Conditional inference forests
determined scale-specifc responses over 20 bufer
distances (50-m to 1000-m) around baobabs and identifed relative variable importance. We modeled presence of fruit, as not all trees produce fruit. For fruiting baobabs, we modeled whether there were few or
many fruits.
Results Conditional inference forests were signifcant at 50-m to 600-m bufer distances. Individual
characteristics of baobabs were the primary drivers of fruit presence, with larger trees more likely to
fruit. Fruit presence was modifed by baobab height
and landscape variables. Land use primarily drove
baobab fruit production category, which was modifed by baobab size and other landscape variables.
The importance of distance to and density of alternate
food resources changed with scale.
Conclusions Individual characteristics and landscape variables both infuence reproductive success
in the bat-pollinated baobab system, and relative variable importance was scale-dependent. The pollinator
landscape is complex and scale-dependent, encompassing not only the distribution of the baobab population but also attractants (pawpaws) and distractants
(fgs) that further infuence reproductive success.
Keywords Baobab · Bat pollination · Individual
traits · Landscape context · Pollination · Reproductive
success
