Genetic tagging is an effective way to monitor survival of released hatchery saugers: Conservation efforts in the Wind River, Wyoming

ABSTRACT Released hatchery-origin fish must survive and reproduce for supplementation to recover collapsed native populations, yet monitoring fitness is challenging, because physical tags are not passed from parent to offspring. Parentage-based tagging (PBT) is a method in which all captive-bred parents are genotyped (i.e., given a molecular tag), and their wild-caught hatchery offspring are identified via genetic pedigree analysis. The sauger (Sander canadensis) is a highly migratory, freshwater percid (perch species), native to central and eastern North America. In the Wind River basin, Wyoming the species’ abundance has declined considerably since 2002, and in 2013 stakeholders initiated a hatchery program to recover the population. We estimated the statistical sensitivity and accuracy of PBT using 17 microsatellites to identify hatchery-origin saugers captured in the wild. We completed in vitro and in silico experiments that demonstrated 98% sensitivity and 99% accuracy of PBT in distinguishing hatchery- and natural-origin saugers. Moreover, our experiments showed that accuracy is robust to factors expected to decrease assignment accuracy, including highly related parents (i.e., full siblings) and differing proportions of true parents included in the analysis. This research highlights that our ability to assign parentage and estimate fitness is high, and that PBT is an effective way to monitor recovery of saugers in the Wind River, basin Wyoming.