A towed camera system for benthic research

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A towed-camera system will support research proposed in my NSERC Discovery Grant. The main goals of my ongoing research program are 1) to investigate the role of biological and physical processes in regulating the structure and dynamics of the shallow marine ecosystem in eastern Canada, 2) to determine the ecological consequences of large-scale shifts in ecosystem state, from kelp beds to sea urchin barrens, on ecosystem function and services (e.g. food production, habitat provision, nutrient cycling), within the shallow subtidal zone and in sedimentary habitats in deeper water; and 3) to develop mathematical models to predict change and identify important causal factors and follow-on effects, which will aid in the assessment of ecosystem health and management of natural resources. The proposed towed-camera system will enable us to greatly extend the depth range of our previous SCUBA-based observations and to explore, for the first time, patterns and processes of connectivity between the dynamic shallow-water system and deep-water assemblages that depend on temporally variable food inputs (in the form of seaweed detritus) from the shallows. Specifically, we will examine patterns in offshore distribution of kelp beds and urchin barrens, and shifts in the interface between these communities that are associated with fluctuations in urchin abundance caused by harvesting and disease. We will measure the transfer rate of algal detritus from kelp beds to deeper sedimentary bottoms (particularly after large storm events such as hurricanes), and record changes in distribution and foraging behaviour of deep-living urchins in response to storm disturbance. In a more general sense, this videographic data will enable us to document patterns of biodiversity in nearshore habitats below the limits of kelp beds, presenting many opportunities for training graduate and undergraduate students in the fundamental and applied aspects of marine ecology.