From "Understanding Northwest Coast Art" by Cheryl Shearar:
People consider Killer Whale to be closely related to humans and also to Wolf. Wolf and Killer Whale are both admired for their hunting skill, strength, intelligence and devotion. Killer Whale is sometimes called wolf of the sea. According to some myths, the first Killer Whale was a supernatural, white furred wolf who entered the sea and transformed. Alternately, a Killer Whale may beach itself and take on the appearance of a wolf in order to wonder the earth, the two beings are physical manifestations of one spirit being or essence
All along the coast, fishers and hunters often applied Killer Whale designs to their canoes and other paraphernalia. Killer Whale depictions may include a human figure, clinging to the dorsal fin as a whale moves through the water. A number of different myths from various regions may be alluded to with such an image. Often, Killer Whale is shown grasped in Thunderbird's talons. Less commonly, Eagle is the captor.