Phenotypic shell markers: Assessment tools for stock restoration ofbay scallops, Argopecten irradians irradians

摘要

One major obstacle to fully testing the effectiveness of stock restoration for bay scallops is the inability to identify, monitor, and assess the progeny from a directly seeded or spawner sanctuary broodstock. As one approach to genetic monitoring, selective breeding studies are underway employing bay scallops with striped shells as phenotypic markers for potential use in stock restoration. Shell markers have a genetic basis, are readily visible, and can be quantified with simple counts in the field. Furthermore, because there is a genetic basis, shell patterns would not be lost as applied or tethered tags and shell paint markers might be. The main objective of this project is to investigate the feasibility of increasing, through selective breeding, bay scallops with distinctive phenotypes of shell markers for field identification to determine the reproductive success and genetic contributions of transplanted populations. In addition, caged scallops are being field tested and monitored for survival, growth, and retention of the shell markers. Estimates of increased frequencies of the phenotypic markers can confirm the success of restoration efforts. Preliminary results indicate a positive response to selective breeding with an increased frequency from 1-5% to at least 50% of scallops with striped shells, and favorable growth and survival.