Jones, G. P., S. Planes, and S. R. Thorrold, Coral reef fish larvae settle close to home, Curr. Biol.15: 1314-1318, 2005
Population connectivity through larval dispersal is an essential parameter in models of marine population dynamics [1-3] and the optimal size and spacing of marine reserves [4-6]. However, there are remarkably few direct estimates of larval dispersal for marine organisms and the actual birth-sites of successful recruits have never been located. Here we solve the mystery of the natal origin of clownfish (Amphiprion polymnus) juveniles by mass-marking all larvae produced in a population using tetracycline immersion. In addition, parentage was established by DNA genotyping all potential adults and all new recruits arriving in the population. While no individuals settled into the same anemone as their parents, many settled remarkably close to home. Even though this species has a 10-day larval duration, one-third of juveniles returned to a 2 hectare natal area, with many settling <100m from their birth-site. This represents the smallest scale of dispersal known for any marine fish species with a pelagic larval phase. The degree of local retention indicates that marine reserves can provide recruitment benefits not only beyond, but within their boundaries. |
