Low Coverage Whole Genome Sequencing Contributes to Understanding Population Connectivity of Jonah Crab (Cancer borealis) for Upcoming Stock Assessment.

Comb, Dylan, Tim O'Donnell, Gloucester Marine Genomics Institute, Gloucester, MA

Over the past several years, Jonah crab (Cancer borealis) has transitioned from a bycatch species of the lobster industry to a targeted fishery that is now one of the most lucrative in Massachusetts, valued at $12.4M in 2018. Despite commercial interest in this species, there is scarce biological information regarding life history or abundance of Jonah crab, and under the current Atlantic State Marine Fisheries Commission fisheries management plan, the fishery is managed as a single homogenous stock from Maine to Virginia. The lack of comprehensive biological data creates a high degree of uncertainty regarding the impact of the fishery and any potential for overexploitation. In preparation for the upcoming Jonah crab stock assessment in 2023, we conducted a genetic population structure assessment to provide necessary data on spatial structure and connectivity. Over 550 Jonah crab tissue samples were collected from Canada to New Jersey in collaboration with commercial fishers and state biologists and low-coverage whole-genome sequencing was used to generate genotype likelihood data for millions of SNP loci. Population genomic data was used to estimate population connectivity and gene regions under selection, which will be combined with tagging, life history, and landing data to aid the Jonah Crab Technical Committee in establishing biologically relevant boundaries for stock delineation.