Coastal Ecosystem Food Web Dynamics
Coastal marine ecosystems are among the most productive and biodiverse ecosystems on Earth and provide critical goods and services to humans. These systems are also under tremendous pressure from direct and indirect human-environment interactions. Our research looks to address how food web architecture influences the structure, function, and resilience of coastal ecosystems by quantifying the sources and cycling of organic matter supporting coastal food webs. Here we work on a wide range of projects both locally in southern New England and around the world. Some examples of recent projects include:
Coastal fisheries competition:
In southern New England, a new competitive interaction is potentially occurring as temperate black sea bass abundance increases in the home range of the iconic Atlantic cod over the last few decades. Understanding the potential for dietary and trophic niche overlap between cod and black sea bass in southern New England will shed light on the potential drivers of their future ecological trajectories, which are necessary for the effective management of these dynamic fisheries and the integrity of Southern New England food webs. In this project, we examined the diet and trophic dynamics of Atlantic cod and black sea bass in southern New England using a multi-tracer approach of stomach content analysis and bulk and compound-specific amino acid isotope analyses.
Movement ecology of southern New England Jonah Crab:
Despite the rapid growth in size and value of the RI Jonah crab fishery in the past decade, management of this emerging fishery has lagged its increased exploitation due to the lack of knowledge of the species’ life history and an associated stock assessment. Our project applies cutting edge molecular isotope geochemistry tools to test a fundamental ecological question about whether the significant size differences in the terminal harvested size of Jonah crab between inshore and offshore harvest zones represents ontogenetic migration of the same population or potentially differential growth patterns of two isolated subpopulations. Simultaneously, we are examining the impact of novel acoustic geolocation tags on Jonah crab mortality rate and molt success to explore the viability of upscaling this new technology development to assess fine scale movement of Jonah crabs across regional fishing zones. This work will fill significant knowledge gaps in the life history of Jonah crabs with direct applications to the successful management of the burgeoning inshore and offshore RI Jonah crab fishery.
Coastal Arctic food web dynamics:
Quantitative assessments of carbon and nitrogen flux are needed to predict ecosystem responses to increasing perturbations associated with climate change, habitat destruction, and exploitation of natural resources. This is especially important in the Arctic where air temperature is warming more than twice as fast than at lower latitudes, resulting in dramatic shifts in habitat availability and ocean circulation, increases in freshwater discharge and permafrost thawing, and expansion of human activities. Arctic coastal lagoons are dynamic systems where terrestrial, freshwater and marine systems converge to provide habitat for migratory birds and fishes and are important locations for subsistence hunting and fishing. In this project, we’re using carbon and nitrogen stable isotope analysis to examine trophic dynamics and the relative contribution of terrestrial organic matter, water column phytoplankton, and benthic phytobenthos to the food webs supporting macroconsumers in Arctic coastal lagoon ecosystems with varying connectivity to riverine and marine ecosystems in Cape Krusenstern National Monument, Alaska.
Publications: (# indicates student author)