Food Web Ecology
In order to understand the importance of estuarine habitats to focal species it is necessary to identify the primary trophic pathways supporting their production. I am particularly interested in how foraging patterns of various species may link adjacent habitats and represent important energy and nutrient subsidies. I have combined stomach content analysis, stable isotope analysis and behavioral studies to better understand trophic connections in mangrove and oyster reef systems. More specifics below:
Behavioral-mediated food web subsides
Many studies of terrestrial-aquatic food web subsides have focused on the role of passive subsides or movements of prey associated with ingrained life history patterns (i.e., insect emergence). However, plastic, behavioral responses of shared prey to multiple predators may also be important in mediating food web subsidies. The mangrove tree crab Aratus pisonii is primarily arboreal/terrestrial, but will jump into the water to escape predation by birds making them vulnerable to fish predators. They are also one of the only species besides insects that feeds directly on green mangrove leaves. We are studying the effects of both predators on crab behavior, how risk varies across the land-sea interface, and how this may control contributions to fish diets.
Collaborators: Betsy Stoner (FIU), Joey Peters (FIU/PSU)
Many studies of terrestrial-aquatic food web subsides have focused on the role of passive subsides or movements of prey associated with ingrained life history patterns (i.e., insect emergence). However, plastic, behavioral responses of shared prey to multiple predators may also be important in mediating food web subsidies. The mangrove tree crab Aratus pisonii is primarily arboreal/terrestrial, but will jump into the water to escape predation by birds making them vulnerable to fish predators. They are also one of the only species besides insects that feeds directly on green mangrove leaves. We are studying the effects of both predators on crab behavior, how risk varies across the land-sea interface, and how this may control contributions to fish diets.
Collaborators: Betsy Stoner (FIU), Joey Peters (FIU/PSU)
Energy flow pathways in oyster reef food webs
Part of my research has involved creating an energy flow food web model for a sub-tropical oyster reef, focusing on trophic pathways important in supporting production of snapper, in addition to other fish consumers. Most previous studies have focused on the functional relationships within oyster reef food webs, especially in temperate systems. This research is among the first to focus on energy flow pathways, particularly in a sub-tropical system. Findings suggest that the primary trophic pathways may be quite different than classic models from temperate systems, even when the focal organisms are similar. Ongoing collaborations are addressing how the relative importance of key trophic connections (oyster-mud crab) may vary
when viewed from energy flow and functional perspectives.
Collaborators: Craig Layman (FIU/NCSU), Jon Grabowski (NEU)
Part of my research has involved creating an energy flow food web model for a sub-tropical oyster reef, focusing on trophic pathways important in supporting production of snapper, in addition to other fish consumers. Most previous studies have focused on the functional relationships within oyster reef food webs, especially in temperate systems. This research is among the first to focus on energy flow pathways, particularly in a sub-tropical system. Findings suggest that the primary trophic pathways may be quite different than classic models from temperate systems, even when the focal organisms are similar. Ongoing collaborations are addressing how the relative importance of key trophic connections (oyster-mud crab) may vary
when viewed from energy flow and functional perspectives.
Collaborators: Craig Layman (FIU/NCSU), Jon Grabowski (NEU)
Foraging trade-offs
Habitat generalists are faced with varying biotic and abiotic conditions across their landscape. Because they maintain such a wide distribution, these generalists may encounter varying prey quality and quantity throughout their range. Optimal foraging models predict that predators should select prey for which energy lost during search and pursuit is compensated for by the energy content of the food. One component of my research examines how a generalist predator (gray/mangrove snapper) undergoes foraging trade-offs across its landscape and the effects of such a trade-off on fitness. This research is focused in the Loxahatchee River and estuary, Florida, USA.
Collaborators: Caroline Hammerschlag-Peyer (FIU), Craig Layman
Habitat generalists are faced with varying biotic and abiotic conditions across their landscape. Because they maintain such a wide distribution, these generalists may encounter varying prey quality and quantity throughout their range. Optimal foraging models predict that predators should select prey for which energy lost during search and pursuit is compensated for by the energy content of the food. One component of my research examines how a generalist predator (gray/mangrove snapper) undergoes foraging trade-offs across its landscape and the effects of such a trade-off on fitness. This research is focused in the Loxahatchee River and estuary, Florida, USA.
Collaborators: Caroline Hammerschlag-Peyer (FIU), Craig Layman