Commercial and sport fisheries are important industries in the Ontario Great Lakes region. Over sixty-five million pounds of fish per year are harvested from the lakes, contributing more than a billion dollars to the Great Lakes economy. Commercial catches include whitefish, smelt, walleye, and perch, while sport fisheries include Chinook salmon, walleye, lake trout, and perch. Sport fisheries are a huge tourist attraction, which helps to build the economy of the Great Lakes region. For example, Great Lakes angler spending generates about $1.5 billion in economic impact annually for Ontario, and contributes to 36,000 full-time jobs. Because many of these commercial and sport fisheries are in decline, the Ontario (& Canadian) government has invested millions of dollars into supportive breeding (the practice of augmenting wild populations by releasing individuals that were bred in captivity (hatcheries)), but many programs have failed to rehabilitate dwindling fish stocks. This failure may in part lie in the lack of knowledge about the genetic architecture of fitness: the genes and genotypes that are associated with individual performance. In addition, most supportive breeding programs mate individuals randomly or attempt to mate dissimilar individuals to maximize genetic diversity and thus minimize inbreeding depression. However, there is an increasing recognition that random mating or genetic diversity does not capture the complexity of genetic quality arising from natural mating dynamics in the wild (e.g. sexual selection). Over the coming years, my graduate and undergraduate students, postdoctoral fellow and I will (i) investigate the genetic architecture of fitness as it relates to supportive breeding programs, (ii) model the benefits of incorporating genetic quality into supportive breeding programs, (iii) examine mechanisms that can increase offspring genetic quality (fitness) arising from natural mating dynamics between males and females (via pre- and post-spawning sexual selection), and (iv) provide guidance and practical information (e.g. new supportive breeding schemes) to managers, in order to improve the genetic quality of captively reared Chinook salmon. The overall goal of this research proposal is to contribute to and improve the supportive breeding programs for Ontario and Canadian fishes (to increase fishing opportunities and tourism) and increase our standing in the field of ecological genetics.
Principal Investigator: Trevor Pitcher
Researchers: Jason Lewis, Jennifer Smith, Adriana Forest