Intellectual Merit: The importance of fluxes across ecosystem boundaries is a characteristic of marine ecosystems that differentiates them from their terrestrial counterparts. From this viewpoint, any comparative analysis of marine ecosystems should address the patterns and degree of connectivity among ecosystems to be of highest utility. Here the investigators will conduct a suite of analyses that seek to quantify the sources, patterns and consequences of connectivity among 10 marine fishery ecosystems that together from the northwest Atlantic coastal shelf ecosystem. By conducting analyses in a hierarchical fashion with smaller ecosystems nested spatially within larger ecosystems they hope to identify scaling relationships in the ecological processes that characterize the dynamics of key species within these ecosystems. This work seeks to quantify the patterns and degree of connectivity among ecosystems in the Northwest Atlantic. Specifically, the investigators will conduct statistical analyses of empirical data from each ecosystem to quantify patterns in univariate, distribution and multivariate descriptors of their structure. They will also undertake time series analyses to describe relationships in the responses of different taxa and groups within each ecosystem. They will use the results of analyses conducted on the highly studied nearshore ecosystems as hypotheses to be tested on the somewhat sparser data of the offshore ecosystems. These analyses will delineate patterns of functional connectivity among ecosystems. They will also construct dynamic models of differing complexity to understand the principal consequences of the connectivity demonstrated in the first two objectives on ecosystem function. Models will include biomass dynamic and coupled predator-prey simulations that will consider the impacts of removals from the overall region globally and more specific patterns of localized spatial depletion.
Broader Impacts: Agencies, at all levels, are seeking to develop ecosystem-approaches to management (EAM) of fisheries in efforts to ensure long-term sustainability of the exploited marine resources and ecosystems. Central to EAM are Integrated Ecosystem Assessments (IEAs), which provide the societal, legal, and scientific basis to examine marine ecosystems at multiple scales -spatially, temporally, and jurisdictionally - and to coordinate the management of coastal ecosystem resources across multiple sectors. The open nature of marine ecosystems is a challenge for IEAs and EAM and particularly so for the Northwest Atlantic Coastal Shelf (NWACS) ecosystem. Key to management in this open ecosystem is assessment of the connectivity among key biota across space and time in the different regions. Here, the investigators will analyze ecosystem structure and function at a range of scales in a suite of interconnected regional ecosystems to support IEA development.
