Marine Larval Ecology - Self-recruitment

Self-recruitment

One of the most important unanswered questions in larval ecology concerns the degree of self-recruitment in populations. For most of the short history of the field of larval ecology, larvae were considered to be passive particles that were carried by ocean currents to locations far from their site of hatching. This led to the belief that all marine populations were demographically open, connected by long distance larval transport. Recent work, however, is starting to show that many populations may be self-recruiting, and that larvae and juveniles are capable of purposefully returning to their natal sites.

Researchers take a variety of approaches to estimating population connectivity and self-recruitment, and several studies have demonstrated their feasibility. Jones et al. and Swearer et al., for example, both investigated the proportion of larvae returning to their natal reef after their time in the water column. Each study found higher than expected (possibly as high as 60%) self-recruitment in these populations, using variations of a typical mark, release, recapture sampling design. These studies were the first to provide conclusive evidence of self-recruitment in a species with the potential to disperse far from its natal site, and laid the groundwork for numerous future studies.