The 65-foot Sea Wolf II and its dozen or so passengers were making their way through the rough waters of the Monterey Bay when something caught their attention.
"We were trying to figure out what was attracting gulls to the area when suddenly we saw splashing off in the distance," says naturalist Roger Wolfe of Soquel, who was among the small crew trying to catch sight of the annual gray whale migration late last month.
But the commotion was not gray whales. The boat had come across an uncommon pod of killer whales. About 40 giant black-and-white predators were 4 miles off Pacific Grove; the crew's resident biologist Nancy Black quickly identified them as "resident" killer whales from Washington and British Colombia.
Less than a week later, the crew would see another 40 resident killer whales, this time a mile off Monterey. Black's still unsure if they were the same individuals, but she is sure the community of killer whales that once remained primarily in the Pacific Northwest is no longer a stranger to points south.
This is the fifth year since 2000, Black says, that these resident killer whales have been spotted in the Monterey Bay, and the sixth year they've been seen in California, a migratory behavior some researchers think the whales have adopted because they're not finding enough salmon, their food of choice, in their native waters.
"They've always been thought to move around in the winter but not as far as California," says Black, one of the state's leading killer whale experts. "If they had been here before, we would have seen them."
The presence of the killer whale this far south has left Black and other researchers wondering what it means for the massive ocean creature, which like many marine creatures is being forced to confront changing conditions to meet its basic needs.
The killer whale, or orca as it's also known, is the largest species of the dolphin family. It can grow up to 30 feet long and weigh as much as 10 tons.
"They're curious creatures, and sometimes come right up to the boat," says Black, who has been observing the animals first-hand for more than 20 years, working at whale-watching outfits like Monterey Bay Whale Watch at Fishermen's Wharf in Monterey and in her free time piloting her own small craft to view them. "But they'd never do anything" to endanger her, she says.
There are several communities of killer whales across the globe, each biologically distinct with its own diet, range and social behavior, and some are regular visitors to the Central Coast. "Transient" killer whales, for example, distinguished by their long ocean passages in small groups and by a diet of exclusively other marine mammals, are known to hunt in the Monterey Canyon.
The resident killer whale, however, brings a different and more dire story line to local waters, researchers say.
The Puget Sound natives, which are believed to feed solely on fish, are an endangered variety, numbering less than 100.
"The question now is are they getting enough to eat," says Howard Garrett, who runs Orca Network, a Greenbank, Wash., non-profit that tracks the killer whales and seeks to raise awareness of their plight. "There are signs that they're not."
Recent sightings reveal what Garrett calls a "peanut head," a depression behind the orca's skull that indicates a lack of blubber - and a possible food shortage.
"They're getting skinny," he says.
Which explains why the resident whales, or at least some of them, have traveled more than 600 miles from the Puget Sound to the Monterey Bay, where they've been spotted at least twice this year, on Jan. 27 and Feb. 2. Their presence in California has been confirmed through photographs sent to Garrett's brother Ken Balcomb, who runs the Center for Whale Research and has been watching the killer whales in Washington for 30 years.
Balcomb's work points to the dwindling population of chinook salmon in the Pacific Northwest as the reason for the killer whale's expanding range.
"If California's proactive effort to recover salmon stocks by setting aside large parcels of ocean as marine reserves prohibiting fishing is successful, the killer whale might just stay there," Balcomb wrote on his Web site recently.
But the chinook population is suffering in California, too. Salmon runs in the Sacramento and San Joaquin rivers, which fuel the population in the Monterey Bay and as far south as Santa Barbara and hundreds of miles north, hit a record low this fall.
"These big sea creatures as they go south will find fewer and fewer salmon," says California Fish and Game spokesman Harry Morse.
Researchers are watching closely where the search for food takes the resident killer whales. How a recovery plan for the resident killer whale, finalized last month by the National Oceanic and Atmospheric Administration, is implemented will, of course, hinge on where the animals travel.
"We can probably do a better job and reach out to California as we learn more about where the whales are going and what is critical habitat," says Lynne Barre, a NOAA marine mammal specialist and one of the architects of the federal recovery plan.
Although there are thousands of killer whales worldwide, Washington's resident whales, which aren't known to interact or breed with other groups, are unique. The whales live in one of three highly social groups centered around older females, who live an average of 50 years but sometimes survive beyond 90, according to the Center for Whale Research. The members communicate through an underwater dialect in which the sounds can travel 10 miles or more, according to the center.
The recovery plan for the killer whales aims to better protect the salmon populations the whales feed on, clean up contaminants in the Puget Sound and perhaps regulate ships whose noises can interfere with communication among whales.
"I'm optimistic," Barre says. "Many of these actions are already being implemented."
Source: Mercurynews.com
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