National Geographic : 2005 Apr
Dozing orcas in Prince William Sound hint at the social ties that help them learn, eat, and survive. "I had never seen any thing like this," says Craig Matkin, a killer whale expert, of the almost 80 animals at rest here. "These whales do and must stick together." salmon. Only AE11, born in 1970, and her calf, AE23, born in 2000, stay close enough for iden tification photos. In fact they're coming straight for the boat. Although a number of older killer whales still carry scars from fishermen's bullets, relations between our species and theirs have improved to the point that orcas from many formerly shy pods no longer avoid boats. Some individuals will come over to swim alongside awhile. In recent years two different young orcas-one from the southern resident community and one from the northern-apparently desperate for company, took to playing with boats and allowing people to pet them. But the mother and calf heading for our boat aren't paying a social visit. They are after a coho that just sought ref uge under the Natoa. AE 11 comes within inches of scraping the hull as she races the fish from bow to stern. Over shooting her target when it jukes to one side, she doubles back in a massive swirl and circles several times while the salmon makes frantic turns inside the orca's orbit. She is not trying her hardest to catch it. Rather, she is herding the fish until her calf joins the hunt. As the salmon tries to break away by diving, she goes deeper, driving it near the surface again. And in between, young AE23 is six, five, four... three feet behind the coho's tail. Ten minutes and multiple spins, rolls, submarine somersaults, and close calls later, we are still scrambling around the deck cheering, mostly for the young whale but with growing respect for this badly vexed fish. At last the lesson, or practice session, is over, the calf swimming off with the salmon in its jaws. Like humans, killer whales are a blend of what they are born to be and what they are taught. The young nurse for as long as three years. Before the flow of milk stops, a mother needs to make sure her offspring is skilled at catching food for itself. Ingrid Visser, the New Zealand biologist, thinks juvenile orcas overcome a nat ural reluctance to enter dangerously shallow 104 NATIONAL GEOGRAPHIC * APRIL 2005 P: )pl~r;f 6 B- bays, where rays flourish, by emulating older animals. Youngsters in other pods learn to take sharks caught on the hooks of fishermen's long lines-again, Visser reports, by observing their elders. Much as transients will drive dolphins into a bay and then form a line to cut off escape, resident-type killer whales in Norway work together to herd herring against the shore. In another coordinated effort, called carousel feed ing, a pod may encircle a herring school in open water, forcing the fish into a defensive ball. The whales then take turns lashing at the huddle with their flukes, stunning mouthful after mouthful. Some Antarctic killer whales will speed in a curve toward ice floes, setting up waves that wash seals off the slick surface into the water.