Theoretical studies suggest that population connectivity (the exchange of individuals among geographically-separated sub-populations that comprise a metapopulation) plays a fundamental role in local and metapopulation dynamics, community structure, genetic diversity, and the resiliency of populations to human exploitation. Recent studies have suggested that the scale of larval dispersal may be smaller than generally thought, particularly within ecologically relevant time scales. A mechanistic understanding of marine population connectivity requires resolution of the biological and physical processes involved in larval dispersal and transport.
Our lab has been studying population connectivity from a variety of approaches: 1) direct empirical measurement of the processes that contribute to larval dispersal; 2) examination of population genetic structure as a means of identifying the scale of exchange over ecological time-scales, and 3) bio-physical modeling to determine the typical dispersal distances, pathways, and critical factors influencing larval dispersal. Our relative focus on each of these aspects has shifted over the years as the field has advanced.
Our funding to support population connectivity questions has been supported primarily via the National Science Foundation beginning with a grant in 1989 and continuing with a second effort in 1995 to study reef fish reproduction and recruitment to the upstream island of Barbados, West Indies. In 2001, we expanded our scope to include the wider Caribbean and utilized new molecular techniques to quantify population connectivity. In 2002, we helped organize a NSF-sponsored workshop on Marine Population Connectivity, which culminated in a dedicated issue of Oceanography on the topic. In 2006, we began a pelagic-to-shore-based coupled study in the Florida Keys as described in "Larval linkages."
The Lead PI on all of these efforts was Robert Cowen.
Titles of early NSF grants on population connectivity
- Organized island wakes & the retention & recruitment of larval reef fishes (1989-)
- Coupling of biological & physical processes responsible for retention of coral reef fish larvae (1995-)
- Assessment of population connectivity in Caribbean reef fishes using microsatellite loci (2001-)
- NSF Workshop on Population Connectivity in Marine Systems (2002)