Diverse trophic linkages generated by an Anolis community couple canopy and understory food webs

Background/Question/Methods

Allochthonous material flows generate trophic linkages between adjacent food webs, thereby affecting community structure and stability in recipient systems. We investigated cross-habitat trophic linkages between canopy and understory food webs in a terrestrial, wooded, ecosystem in Miami Florida, USA. The focal community consisted of three species of Anolis lizards and their prey. We described interspecific differences among three Anolisspecies in the strength and routing of these cross-habitat flows using stable isotope analysis, stomach content analysis, and habitat use data.

Results/Conclusions

All three Anolis species in this study consumed different prey, and occupied vertically distinct arboreal habitats. Despite these differences, carbon isotope and stomach content analysis revealed strong integration with understory and canopy food webs for all Anolis species. Modes of resource flux contributing to the observed cross-habitat trophic linkages included prey movement and the gravity-driven transport of detritus. Our study shows that terrestrial systems are linked by considerable bidirectional cross-system resource flux. Our results also suggest that considering species-specific interactions between predator and prey are necessary to fully understand the diversity of material and energy flows between spatially separated habitats.