There is some question as to whether or not the Orcas had played a role in his death or if he had died from other causes once in the tank. However, in , Tilikum attacked and drowned trainer Dawn Brancheau and killed another trainer in , reopening the debate about the death of Mr. It should be noted that given the number of trainers and park workers they encounter, the number of confirmed attacks remains low. Many groups believe these captive Orcas suffer stress due to the nature of their confinement, leading them to be aggressive to other dolphins and humans alike.
Also, due to the size and strength of killer whales, it is possible that some of these attacks, even those that cause serious injury or death, are not actually a serious attempt to harm the human on the part of the dolphin. Also, dolphins with a history of violent acts may be entirely isolated from human contact to protect the staff. In some cases, trainers may be equipped with oxygen-supply systems to protect them from drowning if they are pulled into the water by a dolphin.
Ultimately, killer whales have been involved in very few attacks on humans, whether wild or in captivity. Orcas basically have the same superpower. Orcas will work together to support and transport their injured mates for weeks at the risk of their own health. People who have spent a lot of time around these whales suspect that they also have a sixth sense or, at the very least, an uncanny sense of timing.
Veteran killer whale watchers and long time researchers all have stories about the ones that got away. Is it too much of a stretch to wonder if they can sense friend or foe?
Some longtime whale watchers are convinced that orcas will perform when they have the chance to endear themselves to humans who are working to save them. Killer whales have also helped humans hunt. In North America and Australia, there are stories of orcas herding fish—and even other whales—to make it easier for fishermen to catch them.
In the late nineteenth and early twentieth centuries, orcas near Eden, Australia, would drive humpback whales into an area known as Twofold Bay in exchange for their favorite pieces of meat—the tongue and the lips. All three pods cooperated together. One pod stationed far out to sea would drive whales in towards the coast, another pod would attack the whale and another pod would be stationed ahead of the whale in case it broke loose.
After a humpback had been trapped, Tom would alert the whalers by slapping his tail and repeatedly breaching jumping out of the water and landing with a splash to summon the humans to finish off the kill.
But Tom continued to herd larger whales for his taste of tongue. When Tom died in —as a result of the teeth he lost—the people of Eden built their whale museum to honor their longtime partner and display his bones. The Australians of Eden had worked with the orcas for almost a hundred years. The indigenous people of the area, the Koori, are believed to have worked in harmony with the whales for ten thousand years. And anyone who has ever seen a killer whale in captivity knows they can be trained to do practically anything in the water.
Killer whales know how to work with humans—and save them—but humans have rarely been inclined to help the killers. The whales off Saturna knew what humans usually did when they came close in their boats. The humans shot them. The initial plan was to tag the orcas, but after talking with Vancouver Aquarium curator Murray Newman, Bigg settled on a more radical idea—simultaneous observations.
Over the course of a weekend, volunteers located along the coast would spot and count the killer whales. For decades, researchers have been performing necropsies on beached orcas, but, until now, no one has amassed all of those data to assess the health of the populations and whether human activities, such as fishing or shipping, may harm the animals. In a study published this month in PLOS ONE , Raverty, veterinarian Joseph Gaydos of the University of California, Davis, and colleagues reviewed the pathology reports of 53 orcas that stranded between and , as well as other data on 35 orca strandings between and The orcas ranged in age from infants to older adults, and in every age category, there was evidence of orcas dying after being struck by ships or entangled in or impaled by fishing gear.
Stephen Raverty: Necropsies on killer whales provide information on how each animal died, and collectively what are the leading causes of death. Blunt force trauma from ship strikes, for example, is quite obvious based on the bruises on an animal.
I look at how quickly they learn behaviors in the wild. Killer whales in Alaska interact with longline fisheries up there. It's known that they can be several kilometers away from the fisheries and as soon as the hydraulics get turned on the whales swim toward them for fish that are coming off the lines. A lot of people say they have big brains. But it's important to take into account that echolocation takes a lot of processing power, as well.
A lot of that gray matter is designated to process those signals when they come back. Their ability to discriminate things with this system is impressive.
They could find something the size of a BB in the bottom of a pool. They could determine the different densities of two objects of the same size. Already a subscriber? Sign in. Thanks for reading Scientific American.
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