Investigating the genetic structure of Atlantic Cod (Gadus morhua) spawning populations following the collapse of the northern cod stock
University of New Brunswick
The Atlantic cod (Gadus morhua), within the Northern cod stock, once served as the economic pillar for Newfoundland and Labrador. After years of overfishing and reduced ocean temperature, the stock population collapsed in 1992, driving many to question the genetic structure for its recovery. Currently, the metapopulation and isolation hypotheses have been proposed to describe the genetic structure of the stock, but there is much debate on which is reliable. The stocks genetic structure will be determined using fin clips obtained from 2001- 2003, from various spawning populations, to indicate whether the stock exhibits panmixia. A double-digest restriction site associated DNA technique was used to identify 846 single nucleotide polymorphisms, and the population structure was determined using the Fixation Index (FST). The FST analysis found no significant differences, therefore, spawning populations of the stock are panmictic. Further research is necessary to obtain a more robust genetic structure for extensive ecological management.