From local to regional seabed maps: Developing the methods and data products needed for marine conservation planning in Newfoundland and Labrador

Maps are essential tools for understanding the environment around us. This is especially true for the global ocean: the majority seafloor habitats are out of sight and beyond the reach of conventional survey methods. In this thesis, I use two case studies to demonstrate the utility of multibeam echo-sounding and biological sampling to map marine habitats in support of conservation planning. Habitat protection is a key pillar in the conservation strategy outlined by Canada’s Species At Risk Act, yet information on critical habitat is not available for most marine species at risk. In Chapter 2, I use high-resolution multibeam, physical samples, and video surveys to identify biologically distinct habitats and delineate potential spawning and nursery areas for Atlantic wolffish. In addition to characterizing and mapping seafloor habitats, this work highlights potential vulnerability of nearshore wolffish spawning habitats to warming coastal waters. Habitat mapping is also important to Marine Protected Area (MPA) design and monitoring. In Chapter 3, I define and map the seafloor habitats of Newfoundland and Labrador’s Eastport MPA to assess MPA design against stated management goals. Despite aiming to protect endangered wolffish, this small MPA does not include suitable wolffish habitats and, unfortunately, contributes little to regional biodiversity. This work highlights the importance of science-driven management and the challenges faced when single-species fisheries closures are redefined as broader conservation measures without adaptive management to support the expanded objectives. These case studies add to mounting evidence that further investment in and effective use of marine habitat maps is key to effective conservation and sustainable management of our oceans. However, multibeam surveys are expensive and time-consuming. In Chapter 4, I outline a method for using low-cost crowd-sourced data to improve seafloor maps at a regional scale and higher spatial resolution than previously possible. I use this method to produce novel data products for over 670,000 square kilometres of the Newfoundland and Labrador shelf, including identification of almost 2000 km2 of previously unmapped tributary submarine canyons. This research advances our understanding of Newfoundland and Labrador waters and presents tools that can be applied to science-based marine conservation planning regionally and globally.