Using Historical DNA to Inform Contemporary Atlantic Cod Fishery Management

Northwest Atlantic cod populations today are at a fraction of their carrying capacity, and U.S. cod stocks are still severely overfished and not recovering, despite management efforts.  These concerns about the sustainability of the cod fishery warrant reevaluating stock structure and spatial distribution, which form the basis for management. Genetic data, tagging studies and larval dispersal models all point toward a complex biological stock structure for U.S. cod inconsistent with current management areas. Historical records suggest an even greater complexity. Intraspecific biological diversity is thought to confer population resilience, and the loss of this biocomplexity is hypothesized to have contributed to the decline of cod populations. To evaluate this hypothesis, a solution lies in using ancient DNA analysis of archaeological cod bone to reconstruct historical population structure. In this study, we extract cod bone DNA from paleo-maritime sites in the Gulf of Maine. Using amplified DNA sequences of a 210 base pair fragment of the Pan I nuclear gene and a 340 base pair fragment of the cytochrome b mitochondrial gene, we compare modern and historical patterns of genetic variation.