Boundary Pass is a busy vessel traffic area of the Salish Sea and is a critical foraging habitat for many cetacean species, specifically Southern Resident killer whales, transient (Bigg’s) and humpback whales. With the shipping lanes passing through this area, whales are at risk of disturbance from underwater noise and, at times, from close vessel proximity. However, DFO has created a seasonal vessel no-go zone (Interim Sanctuary Zone) for whales to reduce acoustic and physical harassment in the region.