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| DYING BREED | |
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August 30, 2000 |
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MIKE JAMES: In the San Juan Islands of northwest Washington State, the biggest draw on summer weekends is the Orca, the killer whale. Spectacular to watch, the killer whales reside here in three large pods, all feeding in the salt waters of Puget Sound. But the whales are dying, and local residents here wonder if the Orca can survive here at all. MARK ANDERSON: We're losing them through death at such a high rate and increasing rate that the chances of them being around at all in three to five years are very, very small. MIKE JAMES: Mark Anderson helped found the local San Juan Whale Museum. He says 98 Orca hunted in the three pods just four years ago. The count is down by 18 whales now, a fifth of the population, to just 80. The decline worries local researchers like Ken Balcomb, who directs the Center for Whale Research, a monitoring service that tracks the whales in the islands. The center follows the killer whales by boat, taking photographs of the pods as they hunt for food. The animals are easily identified by the distinctive notch marks and shapes of their dorsal fins. It's clear to Balcomb from recent photos on display in his office that juveniles, the younger whales, are dying now at a much faster rate than ever before. He blames the decline on pollution, and on the dwindling supply of salmon, the major source of food for killer whales. KEN BALCOMB: We do see the animals starving during the course of what historically has been the best food supply available, middle of the summer when you have a lot of salmon. There's just not as many there, and we see backbones like an old sawback horse, see them wasting away and eventually disappearing, dying. MIKE JAMES: Wasting, the researchers call it, an indication that some whales are losing blubber. The depressions behind the head, what whale-watchers call the sawback horse look, or peanut- head, are the sure signs of poor nutrition. Crowds still gather at public fish ladders as the salmon fight their way through man-made obstacles to reach spawning grounds. But fewer fish make this journey now. Compared to historical levels of a century ago, only half the number of salmon are returning to northwest rivers. Several species, including the Chinook, which makeup two-thirds of the killer whale diet, are listed as threatened or endangered. KEN BALCOMB: Now there are too few salmon to feed the whales year round. They're having to turn to other food resources like bottom fish, flat fish, rock fish, that are much higher in contaminant levels than the salmon were. MIKE JAMES: Contaminant levels are the other reason scientists give for the increasing killer whale mortality rates. Polychlorinated biphenyls, PCB's, a by-product of manufacturing through most of the 20th century, are the most lethal of the chemicals dumped into the global environment. They're absorbed by organisms on the ocean bottom, work their way up the food chain, and are eventually absorbed by the Orca in high concentrations. SPOKESMAN: A biopsy from a whale... MIKE JAMES: Peter Ross, a research scientist with Canadian fisheries in British Columbia, recently published a study based on biopsies from living whales. His findings show extremely high PCB counts in Puget Sound killer whales. PETER ROSS: In fact, the southern resident killer whales and the transient killer whales are now three to five times more contaminated with toxic PCB's than the St. Lawrence River belugas. The St. Lawrence River belugas were long considered the most contaminated marine mammals anywhere on the planet. MIKE JAMES: These industrial contaminants can make marine mammals more vulnerable to disease, and may affect reproduction rates. Ken Balcomb believes PCB's killed J18, a juvenile whale who died at age 22 -- 15 to 30 years short of his expected life span. MARK ANDERSON: I have a question for you. WOMAN: Yeah? MARK ANDERSON: Were doing a petition. MIKE JAMES: Mark Anderson isn't waiting for healthier salmon runs, or expecting any changes in PCB counts. He's petitioning to keep whale watchers from hounding the killer whales. His argument is that all the noise and commotion from whale- watching boats, dozens of them sometimes, disrupts killer whale feeding patterns. The Orca use sonar sound to hunt and communicate. Anderson believes the boats disrupt their sense of sound. MARK ANDERSON: These are probably the most exquisite users of sound in the animal kingdom, and they live in water, and that water carries sound exquisitely well, and all these boats have engines, just about. So it's a big problem in terms of their ability to navigate, communicate, and capture salmon. MIKE JAMES: There's some evidence to back up Anderson, but none of it is conclusive yet. Researcher Jody Smith and her colleagues track whale and boat movements on the western side of the island chain. The data they've collected so far suggest that without close- in boat traffic, the movement and breathing pattern of individual whales is consistent. But when boats pursue the whales too aggressively, the Orca moving and feeding pattern is disrupted. Smith is reluctant to draw conclusions yet, but she says the distraction could inhibit the whales as they hunt for food. JODY SMITH: My concern as far as foraging would be how much energy they're expending getting around the boats, moving around the boats, and as well as looking for food. If you have boats that are spread out, and these whales are spread out looking for food, that may impact them. They may have to expend more energy. MIKE JAMES: Tom McMillen, one of many boaters in the islands who run whale-watching tours, doesn't agree. He says killer whales have existed comfortably with boat traffic for years without consequence. In fact, McMillen argues that bringing people out to see the whales actually helps because it spreads the word about real problems. TOM McMILLEN: I think that's the way we need to look at it, is to educate the public that we do have a serious problem here with this. It's not just the whale watchers. It's our 100 years of unconcern about it. MIKE JAMES: Whale museum founder Mark Anderson is impatient. He believes all the other fixes take too long. Going after the boats is the only thing that will help the whales now. MARK ANDERSON: If we do the chemical thing, that's going to take us two decades. Those chemicals are already in the sea sediments now. They'll be leaching out for decades to come. If we go after the salmon... well, we're going after the salmon. They're endangered now. We're doing everything we can. It's going to take us decades to solve that problem. There won't be any whales here at this rate. So all we can do, the only thing that's left, is to try to reduce the pressure that comes to them from human boat interactions. And hopefully by doing that, maybe we save them. There's no guarantee. MIKE JAMES: Balcomb the whale watcher dismisses the boat traffic argument as frivolous, not a real issue anymore. The scientists who have studied killer whales admit they don't know exactly what's happening. The best scientific bet of the moment is that a combination of stresses is killing these animals. |
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