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Based on the recent population trends, U.S. environmental groups will soon petition the National Marine Fisheries Service to declare the resident whales endangered.
Doug DeMaster, a marine mammal expert at the fisheries service, says there is a 50-50 chance that the agency will list the orcas as endangered, which would then require the service to decide on steps to protect the animals.
"There's certainly concern. They [the pods] are small and declining," DeMaster said. "Contaminants are high--high enough at least in lab animals to compromise immunity. There's also a lack of salmon and there are threats from whale watching. These things are all potentially problematic for them."
What worries researchers is the experience of other marine mammal populations that have been heavily contaminated with PCBs.
Until the orca discovery, scientists had thought that beluga whales off Quebec, which are stricken with tumors and reproductive problems, were the world's most chemical-laden marine mammals.
The only animals known to contain more PCBs than the Pacific Northwest's orcas are dead--Mediterranean dolphins that died en masse from a virus epidemic.
The fates of the dolphins, belugas and the European harbor seals that Peter Ross studied could be a warning for orcas. With PCBs known to weaken animals' immune systems, could a mass die-off be a mere virus away?
Whale Watchers May Be Adding Stress
Life can be stressful for the region's orcas, and not just because of industrial chemicals. On a sunny Saturday afternoon, Kari Koski is navigating a boat around the San Juan Islands, the Pacific Northwest's most popular whale watching destination. But Koski is not here to watch the whales. She is here to watch the people who are watching the whales.
Spotting a boater headed toward a pod of killer whales, she picks up her megaphone.
"Please shut off your engines and let the whales pass you," she says. Within minutes, she sees another private boat maneuvering too close. "Vessel Cygnet," she says into the megaphone. "Make sure you stay at least 100 yards away and go slowly while traveling with the whales. Thank you."
Koski is a coordinator for the Whale Museum, which patrols the crowded waters around the San Juan Islands to ensure commercial and private boaters don't harass the whales.
Biologists are concerned that the traffic, which exploded in the 1990s, may be stressing the whales, contributing to the reduction in their survival rates. Boats could be obstacles to their hunting and the engine noise could disrupt their communication.
Most whale-watching companies have agreed to follow guidelines set in recent years by the Whale Museum. Boat operators say they are, for the most part, sensitive to the animals and able to police themselves. They fear that their industry is a scapegoat for the problems facing the orcas when there is no evidence they are harming the animals.
Still, the museum's Soundwatch crew each year detects more than 600 violations by the companies of voluntary guidelines that most whale-watching outfits have agreed to. The flotilla of private sailors and kayakers who sometimes surround whales in the narrow straits commit many more.
Few other sea creatures in recent history have come into such close contact with so many people.
By all accounts, the region's killer whales, once the epitome of wild, have become urban dwellers.
Orca Facts
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