Importance of Metapopulation Connectivity to Restocking and Restoration of Marine Species

Abstract

We examine the impact of spatial processes on the efficacy of restocking in species with varying forms of population or metapopulation structure. Metapopulations are classified based on spatial complexity and the degree of connectedness between populations. Designation of effective restocking sites requires careful attention to metapopulation dynamics; populations in the metapopulation can differ dramatically in demography and connectivity, and the sites they occupy can vary in habitat quality. Source populations, which are optimal for restocking, can be distinct geographically and may be a small percentage of the metapopulation. Sink areas, where restocking is almost certain to be fruitless, can nonetheless serve as productive locations for habitat restoration since larvae from source reefs are likely to recruit to these areas. Effective restocking of metapopulations is most likely to be attained by selection of optimal source populations; inattention to metapopulation dynamics can doom restoration efforts with marine species.

Keywords:

• metapopulation dynamics
• source-sink dynamics
• restocking
• restoration

ACKNOWLEDGEMENTS

Funding was provided by (1) the Chesapeake Bay Office of the National Oceanic and Atmospheric Administration through the Blue Crab Advanced Research Consortium, and (2) the Norfolk Office of the Army Corps of Engineers (D. Schulte, Program Manager). We are grateful to Senator Barbara Mikulski for support of the program. This is contribution 2865 from the Virginia Institute of Marine Science.