The green sturgeon lives in the Pacific Ocean, from Mexico to Alaska. In Canada, it is occasionally found on the West Coast in marine waters or in the lower reaches of large rivers. Green sturgeon sightings have been reported from the lower Fraser, Nass, Stikine, Skeena and Taku rivers of British Columbia. Green sturgeon tend to lumber along river bottoms and ocean floors. Younger green sturgeon call the lower reaches of coastal rivers home until they reach four years of age, when they are large enough to move out to the ocean. They return to rivers as adults to spawn. Unfortunately, very little is known about abundance and distribution in Canada. Green sturgeon spawning and rearing has not been documented in Canada, only in the US. The species may occur in Canadian waters only for feeding.

Green sturgeon have a prehistoric look. Not surprising, since they have pretty much remained unchanged for many millions of years. They are one of the world's most ancient species. Like a smaller sibling to the enormous white sturgeon, the green sturgeon is one of the largest and longest-living species of fish: reaching up to 70 years in age, up to 2.3 metres in length, and weighing as much as 159 kilograms. These dinosaurs of the deep have four barbels-food-sensing whiskers-in front of their mouths, which are located on the underside of their long snouts. And instead of scales, they have denticles-tiny toothlike projections that protect their bodies. But most notable about their appearance are the rows of sharp bony plates that armour their sides and backs, making them look prehistoric. Also, green sturgeon have dark olive-green bodies, with a single dorsal fin located in front of a sharklike tail.