Indicators of benthic condition at the Gulf-scale: megabenthic community structure

Ocean ecosystems are increasingly stressed by human-induced changes in their physical, chemical and biological environment. Among these changes, warming, hypoxia, acidification, and invasive species are a few of the stressors encountered in Canadian waters. This project will quantify stressors within the Gulf of St. Lawrence (GSL), describes the link between stressors and epibenthic macrofaunal communities in the GSL and Strait of Georgia (SoG), and develop indicators of benthic condition based on these communities. Through data integration of anthropogenic stressors (e.g. fishing pressure, noise, shipping activity, coastal population density) we will create environmental layers from data on stressors that are available in disparate formats and institutions for the Gulf of St. Lawrence; these have been assembled for the SoG. Four categories of information will be combined: (i) spatial data on the location and intensity of activities; (ii) types of stressors resulting from these activities; (iii) relative impact of activities on habitats; and (iv) the extent of stressor effects. Maps of cumulative impacts will be created using published methods. Annual extensive biological sampling for commercially fished species (including by-catch) is done on both coasts within DFO multi-species trawl surveys. The taxonomic groups included in by-catch, therefore, represent the most logical target for monitoring the status of the environment as these surveys will continue and the data made available each year.