UC Marine Council

Several species of rockfish currently suffer from overfishing in California and remediation is required to replenish depleted stocks. Due to precipitous declines in several species, it is clear that both managers and research must focus on clarifying population dynamics and spatial connectivity of rockfish populations. All aspects of fisheries management, including ecosystem-based fisheries management tools, require knowledge of the spatial scale of genetic exchange or movement of individuals among populations and degree to which this renders stocks self-replenishing. Population genetics is one of few tools available that directly measures levels of connectivity among marine populations. My dissertation research examines genetic patterns and consequences of larval dispersal for two species of exploited rockfishes, blue and kelp rockfish, both of which inhabit nearshore rocky reefs and kelp forests along the California coast and are targeted by nearshore commercial live-fish and recreational fisheries. My goal is to characterize the effect of pelagic duration on the genetic structure of adults and of settling juveniles, and to analyze whether juveniles from different year-classes have similar patterns of genetic structure. I am using several microsatellite loci to analyze the population structure of young-of-the-year and adult rockfish. The high level of polymorphism inherent in microsatellite loci will provide a sensitive tool for finding subtle differences within and among adult samples and settling juveniles. By simultaneously describing the genetic structure of both juvenile year-classes and adult populations, this study will reveal much more about movement of larvae and constraints on reproductive output of adult populations than previous studies that have examined either larvae or adults alone. My dissertation research is designed to address critical questions on connectivity of rockfish in the coastal marine ecosystem, such that the results of this work can be directly applied to the management and conservation of exploited rockfish species.