Genetics and hatchery management: A parentage-based tagging approach to blueback herring conservation

Abstract

Blueback Herring Alosa aestivalis populations throughout the East Coast have declined precipitously since the late 1980s and were listed as a Species of Concern in 2006 by the National Oceanic and Atmospheric Administration. Natural resource agencies are attempting to restore this species to viable and sustainable levels with fry stockings cultured in hatcheries. To evaluate the long-term contribution of stockings to populations, agencies need an accurate method to track these stocking efforts. Genetic parentage-based tagging is recognized as a feasible means of assessing hatchery contribution of stocked fish to rivers of interest. However, Blueback Herring lack a reliable set of genetic markers to conduct parentage-based tagging. To this end, we analyzed previously described microsatellites as well as new microsatellite markers identified through NextGeneration sequencing to create a suite of 14 Blueback Herring markers useful for parentage-based tagging. The markers were successful in parentage analysis for Blueback Herring collected from the Chowan River, North Carolina. An additional challenge in the management of Blueback Herring is the ability to phenotypically distinguish Blueback Herring from the closely related Alewife Alosa pseudoharengus. Furthermore, recent studies provide evidence that these two species, collectively referred to as river herring, may be hybridizing with one another in some systems. Microsatellite marker AsaC334 can be utilized to discriminate between the two species, as well as to identify their F1 hybrids, thereby providing another genetic tool for hatchery management.