The Bloody Sea

Killer whales have been horrifying researchers and the public as they mercilessly devour grey whale babies and hunt great white sharks for their lives, both signs of more aggressive hunting patterns which may be connected to overfishing.

Sharks have long been canonised by human culture as the top predators of the sea, but killer whales have been fighting in recent years to take away that title. It was reported last week that orcas are hunting and killing great white sharks off the South African coast. Even more gruesome, the orcas are more concerned with devouring the sharks’ livers, which is filled with an oil called squalene and other nutrients that killer whales crave. Yet even with their tasty organs, killer whales attacking great whites is still a rarity. “This is the first confirmed account of an orca predation on a white shark from South Africa,” Marine Biologist Alison Kocks from South African National Parks told Gizmodo, “It’s mind-blowing to think that a white shark of that size (almost 5m) was a target.”

These aren’t the only killer whale attacks in the news recently. Just two weeks ago, a pod of orcas went on a killing spree as they hunted a small family of grey whales near Monterey Bay, California. Though orcas hunting grey whales is not an unusual behaviour, it was the speed of these attacks which fascinated local researchers. Four whale calves were killed in the span of a single week, an impressive rate for these carnivores, and one calf was killed in less than 20 minutes as a whale-watching tourist boat observed in horror. “This was almost a record for how quick the killer whales attacked the mother and calf,” Local marine biologist Nancy Black told the San Francisco Chronicle. She had been observing this pod and its feeding frenzy, and even after studying whales for decades, has never witnessed an orca hunt like this. “This has never happened in my thirty years,” Black told the Chronicle “Just to witness that out in nature when you usually see that kind of thing on television is really spectacular.”

Though these attacks appear to be isolated incidents, there has been a growing environmental concern amongst the scientific community about killer whales becoming more aggressive in their hunting patterns. The U.S. National Oceanic and Atmospheric Administration claims that killer whales may be responsible for 35% of the mortalities amongst grey whale calves, and the orcas’ increasing predation has been cited as a major factor in declining sea mammal populations, including the stellar sea lions in British Columbia and the sea otters of the Alaskan coastline. While a more comprehensive study must be done to find the true reasons for this aggressive hunting, one obvious factor is the declining populations of killer whale prey due to global overfishing and whaling. According to World Wildlife Fund, 85% of the world’s fisheries have been already been drained of harvestable marine life, yet the economic demand for fishing remains as high as ever. We can assume that as we continue to empty the ocean, its killer whales and other apex predators will become more desperate and more violent as they compete for survival.