Tropical deforestation reduces plant mating quality by shifting the functional composition of pollinator communities

Deforestation can impact the quality of pollen received by target plants (i.e., delivery of incompatible pollen, self-pollen, or pollen from closely related individuals). Such reductions in plant mating quality may be direct, when deforestation reduces plant population size and the availability of pollen donors, or indirect, when decreased mating quality results, for example, from shifts in the composition of the pollinator community. As most flowering plants depend on animal pollinators for reproduction, there is a need to understand the direct and indirect links between deforestation, pollinator community composition, and plant mating quality.

We quantified the direct, pollen-donor-mediated and indirect, pollinator-mediated effects of deforestation on mating quality in Heliconia tortuosa, a tropical herb pollinated by low- and high-mobility hummingbirds. We used a confirmatory path analysis to test the hypothesis that deforestation (amount of forest cover and forest patch size) inf...