Marine Biologists Finally Know What's Killing Orcas in the Atlantic — And It's Terrifying

There is a whale swimming off the coast of Ireland right now who has not seen a calf born into his family in over thirty years. Not one. He is one of only two orcas left in a group that used to be ten. And when marine biologists finally figured out why, they realized the killer was not in the water anymore. It had already left. For most of the last century, when people thought about what threatens a killer whale, they pictured something loud. A boat propeller. A fishing net. A harpoon. Something you could point a camera at and say, there, that is what did it. But the orcas dying out in the North Atlantic right now are not being hunted, and they are not sick in any way a vet could diagnose by looking at them.