In 2008, the Ocean Tracking Network (OTN), with support from Fisheries and Oceans Canada (DFO), started building the Halifax Line—an array of bottom-anchored receiver units that can detect acoustically tagged species off the coast of Nova Scotia. Today, it is the world’s longest receiver line, stretching from the coast to the Scotian Shelf—a distance of approximately 200 kilometres. 

The Halifax Line allows researchers to monitor a rich diversity of resident and migratory marine life along the continental shelf—to date, marine species tagged in more than 20 OTN projects have been detected on the line. Data is off-loaded from the receivers using marine autonomous vehicles (gliders). In 2014, OTN and industrial partners pioneered the autonomous off-load of data from bottom-mounted acoustic receivers to the Wave Glider. It is now a regular, cost-effective alternative to manual data retrieval using ships. 

Results help researchers better understand the distribution of marine species in the area and inform conservation efforts and management planning.