It keeps dolphins, walruses, sea lions, an orca, and beluga whales. Charles Morris observed the Acadians at Minas hunting beluga whales. The Mackenzie estuary is also a calving area for beluga whales. The narwhal is most closely related to the beluga whale. The narwhal and the beluga live only in the Arctic Ocean. Like the beluga, narwhals are medium-sized whales. Narwhals are medium-sized whales, and are around the same size as beluga whales. The Caspian fishing industry concentrates on the dwindling stocks of sturgeon and beluga. The Caspian fishing industry is concentrated on the dwindling stocks of sturgeon and beluga. The narwhal is the only other species within the Monodontidae besides the beluga. Monodontids consist of two species&colon; the beluga and the narwhal. A few species, such as the beluga whale, lack them. IUCN classifies the beluga as critically endangered. Both these characteristics are shared by the beluga whale. Beluga caviar is considered a delicacy worldwide.