Unique to Canada, Atlantic whitefish have been reported only in the Tusket River and Petite Riviere watersheds in southern Nova Scotia. Anadromous Atlantic whitefish were believed to inhabit coastal waters during the summer months. Evidence suggests that they fed on amphipods, small periwinkles and marine worms.

The Atlantic whitefish has silvery sides, a silvery-to-white belly, and a dark blue-to-dark green back. The fish has an elongated body and a mouth at the end of its snout rather than under its head. Adult fish range from 18 to 40 cm in length. The Atlantic whitefish's dorsal fin and forked tail fin are dusky in colour; the lower fins are light. The Atlantic whitefish also has a small, fleshy fin between the dorsal and tail fins, which is typical of members of the salmon family.