Thanks to aquariums where orcas serve time as star attractions, and movies like Free Willy , loveable, chatty resident whales with their close-knit families and seafood diet have captured the global imagination and become the default image not just for orcas but for every whale from belugas to blues. Resident killer whales travel and hunt in close-knit family groups, constantly communicate, and feed on specific types of fish, determined by the part of the world they live in.
On the west coast of North America there are two groups of residents—the northerns, who roam between southeast Alaska and southern. Vancouver Island, and the southerns, who live along the rest of Vancouver Island, including the waters near Saturna. These whales travel all the way down to California. These whales are larger, with sharper dorsal fins.
They hunt in packs like wolves—the mammal they have often been compared with by anyone who has seen them hunt. And their prey includes much larger whales—like minkes, grays, and humpbacks. They are also known to eat other animals that have wandered into or near the water—including birds and moose.
Old Tom and his clan were Australian mammal eaters. Since humans would never have qualified as a reliable food source, our species was never sampled. But orcas use echolocation to lock in on their prey. Another possible explanation is that, unlike our species, orcas would never harm another creature they consider intelligent.
His research led to the southern residents being placed on the endangered species list in Canada in and in the U. Today, the southern residents are considered one of the most endangered populations of any species on the planet. In , the U. National Marine Fisheries Service declared the southern resident killer whales one of the eight most endangered marine populations in America, and they are the only officially endangered orca population in the world. At the start of spring , after a year that saw the biggest baby boom since the s, there were only eighty-three southern residents in the Salish Sea.
But in , the belief was that there were too many killer whales, they were ferocious, and, at best, they were a pest that should be eradicated.
The young whale drowning off the coast of Saturna was a southern resident, which meant the only item on its menu was Chinook salmon. In , it was the salmon diet that had earned killer whales their designation as public enemy number one. Fishermen blamed the killer whales, which were swimming beyond their usual hunting grounds in search of sustenance.
At the very least, we can admire and respect these creatures, and be grateful to Natsilane for commanding the killer whale to follow the universal rule.
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In the North Pacific, scientists have identified resident orcas, which tend to have small ranges — hence the name — and specialize in catching fish. Bigg's killer whales, or transient orcas, can also be found in the North Pacific. These orcas travel great distances and hunt mammals such as seals and whale calves.
Offshore orcas can also be found in this region. They live far from coastlines and have been seen eating fish and sharks, but relatively little is known about them. Type 1 orcas are generalist eaters and have been observed eating fish and seals around European countries, including Norway and Scotland.
Type 2 orcas are rarer and mainly eat other whales and dolphins. Scientists didn't have sufficient data when it was last assessed in due to the uncertainty regarding its taxonomic classification — whether orcas should be split into different subspecies or species. The IUCN noted that as a single species, the killer whale is abundant and widely distributed. However, they still face threats from human activities and some regional populations, such as the orcas dependent on bluefin tuna in the Strait of Gibraltar, have declined significantly.
Human civilizations around the world kill orcas directly and indirectly. They are still hunted for food in small numbers, or as a means to control their population, in Greenland, Japan, Indonesia and the Caribbean, according to the IUCN.
Contaminants in the ocean and seas, such as chemicals and oil, pose a threat to orcas along with disturbance by boats, overfishing and other disruptions to their food supply and climate change, according to IUCN. Killer whales are protected in the U. Southern resident killer whales are also listed under the Endangered Species Act as they are at particular risk of extinction, due to threats like noise from boat traffic and a decline in the salmon population — their preferred food.
A SeaWorld orca named Tilikum was the focus of the popular documentary "Blackfish," which took a critical look at killer whales in captivity. Tilikum was involved in three human deaths, including that of SeaWorld trainer Dawn Brancheau in The documentary created a public backlash against SeaWorld, and in the marine park chain announced that it was ending its killer whale breeding program, Live Science previously reported.
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