Cooperative research sheds light on population structure and listing status of threatened and endangered rockfish species

Abstract

Population genetics has increasingly become an important tool for determining appropriate taxonomic units for managing species of conservation interest. Yelloweye rockfish (Sebastes ruberrimus), canary rockfish (S. pinniger) and bocaccio (S. paucispinis) in the inland waterways of Puget Sound (PS), WA, USA were listed under the U.S. Endangered Species Act (ESA) in 2010. These listings relied heavily on evidence from other species that these populations were ‘discrete’ taxonomic units because little information was available for these species in PS. To fill this data gap, we collaborated with recreational fishing communities in PS to collect tissue samples and used population genetics analyses to determine whether samples from PS were genetically differentiated from samples collected from the outer coasts of the U.S. and Canada. Multiple analyses using restriction-site associated DNA sequencing data showed that yelloweye rockfish in PS and British Columbia, Canada were genetically different from coastal populations, while canary rockfish showed no genetic differentiation. These results support hypotheses that the genetic connectivity of rockfish populations is based on interactions between life-history characteristics and oceanographic conditions. These data also support the ESA designation status and the expansion of protected geographical boundaries for yelloweye rockfish but also suggest canary rockfish in PS are not a ‘discrete’ population and may not meet the first criterion of the ESA, as initially assumed. Collaboration among agencies and fishing communities, and cost-efficient genetic analyses provided a framework for collecting and analyzing data essential to the conservation and management of threatened and endangered species.