Evolutionary Ecology and Conservation Biology of Fishes

My research focuses on the tremendous variability in reproductive strategies within and among natural populations. Such life history variation can be reflected by individual differences in age & size at maturity, number of eggs per female, and offspring size. To what extent is the source of this variability genetic, environmental, or some combination thereof? This is a fundamental question to evolutionary ecology and conservation biology. Firstly, the source of variation determines whether life history responses to environmental perturbations, such as habitat alteration and harvesting, will be rapid, slow, or indeed whether they will occur at all. Secondly, the nature of the life history response, i.e., the change in reproductive strategy produced by the environmental change, can affect a population's ability to recover from collapse, persist through time, and sustain exploitation.My proposal integrates molecular genetics with field and laboratory research. My general objectives are: 1) to determine how different reproductive strategies are maintained in variable environments; 2) to determine how populations differ in their ability to respond to environmental change; and 3) to identify factors that affect the recovery of depleted species. One study asks why very small (8cm) and very large (100cm) males are able to co-exist in populations of Atlantic salmon. Another builds upon 25 years of research on brook trout to understand how natural populations differ in their ability to respond to environmental change. Other work examines factors, such as mating behaviour, hypothesized to hinder the ability of species such as Atlantic cod to recover following collapse. From a practical or applied aspect, the impact of the proposed research lies in its potential to: (i) forecast responses by fish to climate change; (ii) understand why some numerically collapsed commercial species have not recovered; and (iii) determine whether human-induced selection (through fishing) can genetically alter the ability of individuals and populations to respond to environmental change.