Orcas, or killer whales, are black and white whales that, from a distance, look a little like dolphins or porpoises. But get closer and there’s no mistaking these giant predators. Killer whales are opportunistic feeders and prey on virtually any large marine animal available. The stomach of a killer whale found stranded near Prince William Sound contained a harbor seal, a harbor porpoise, and a Steller sea lion. They have also been observed to prey on river otters, squid and several species of birds and may even leave the water to grab seals and sea lions from the shore. When preying on large animals such as gray or humpback whales, the killer whales may attack as a pack, tearing away at the prey animal from several angles. Killer whales have no natural enemies other than humans. Orcas typically travel in pods, but occasionally, for reasons scientists don’t understand, individual orcas may be ostracized from their pods. These whales tend to be more aggressive and predatory than whales in pods. Though orcas are pretty scary to marine mammals, it is extremely uncommon for human-orca problems.

Where to find them:

Killer whales are found throughout the marine waters of Alaska but occur most commonly over the waters of the continental shelf from the Inside Passage through the Aleutian Islands and northward into the Chukchi and Beaufort seas

When to come:

Killer whales migrate northward throughout the Bering Strait in the spring as the pack ice retreats. They leave the Beaufort and Chukchi areas in the fall when the ice advances.