Grant: Discovery Grants Program - Individual

It is well known that fish are parasitized by all sorts of different types of parasites, and that they form enormously rich parasite communities, at both the level of individual fish (local parasite community) and the level of habitat (parasite species pool). These communities are known to vary in membership and structure with host life history and environmental factors (latitude, longitude, hydrological regimes, habitat succession, and ecosystem health). What is missing from all of this research is a critical study of parasites of very young fish and as a result we have little information on sequences of early colonization by fish parasite communities. We propose studying the development of parasite communities of brook trout in two experimental study lakes in the Cape Breton Highlands, focusing on the sequence of initial colonization/development of the parasite communities. What is also missing from the mentioned research is the study of subsequent dispersal of fish parasite communities among host cohorts in terms of real biomass. Thus, in the fall of each year, we will undertake mark-recapture to estimate the numbers of trout in each cohort. This information will be integrated with basic prevalence (%), intensity (mean number of parasites/infected fish) and parasite weight to create data that will allow an estimate of the biomass of the entire parasite community in relation to that of the host trout. All of this will be interpreted in relation to the known life history of the parasites and should provide food for thought in broader issues of how biological communities form and how parasite biomass fits into local food webs.