Grant: Discovery Grants Program - Individual

Species distribution and community structure are key ecosystem properties. Rocky intertidal systems have been often important to understand the factors influencing such properties, as these habitats are easily accessible at low tide and host relatively small organisms, facilitating field research. For years, intertidal communities were thought to be structured mainly by local processes such as disturbance and interspecific interactions. Recent research, however, has found that nearshore pelagic traits (e.g., seawater temperature, planktonic food supply) can influence benthic intertidal traits (e.g., recruitment, growth, and intensity of interspecific interactions) at larger scales, raising the concept of benthic-pelagic coupling (BPC). Common relationships have been identified between benthic and pelagic traits, but most research has been done on coasts dominated by upwelling (the Pacific American and Chilean coasts), leaving a knowledge gap for other coasts. I will use Canada's Atlantic coast to investigate BPC for a region where upwelling is much less prevalent and downwelling more common. Using permanent intertidal locations spanning the 530 km of Nova Scotia's Atlantic coast, I will first determine the latitudinal and interannual variation in algal and invertebrate abundance, barnacle and mussel recruitment and growth, and community structure. Using data from intertidal loggers and satellites, I will also determine the latitudinal and interannual variation in nearshore phytoplankton abundance (as chlorophyll- a concentration) and particulate organic carbon (both traits being food for barnacles and mussels), air (at low tide) and seawater (at high tide) temperature, winter ice cover (on northern shores), and the frequency of upwelling and downwelling. Then, I will unravel relationships among those pelagic and benthic traits to identify potential influences. I will then test possibly important intertidal mechanisms influenced by pelagic traits through field and laboratory experiments. At the end of my proposed 5-year research program, I will produce a conceptual model of the main interactions among pelagic and benthic traits that shape rocky intertidal species distribution and community structure along Canada's Atlantic coast. In this way, my research will contribute to develop BPC ecological theory and will generate a baseline dataset valuable to predict and understand future changes in this coastal system.