An orca leaps out of the water near a whale-watching boat near the San Juan Islands. (AP Photo/Elaine Thompson, File)

An orca leaps out of the water near a whale-watching boat near the San Juan Islands. (AP Photo/Elaine Thompson, File)

To avoid extinction, orcas need more chinook and less noise

According to a new study, southern-resident killer whales could vanish within a century.

By Lynda V. Mapes / The Seattle Times

SEATTLE — Orca whales are on a path to extinction within a century unless they get a big increase of chinook salmon to eat, and significantly quieter seas in which to find their food, a new study has found.

The research, published in the journal Scientific Reports, evaluated the relative importance of known threats to the survival of southern-resident killer whales, the salmon-eating whales that frequent Puget Sound.

An international team of scientists reviewed 40 years of data and the threats of lack of food, pollutants and excessive noise under different future scenarios.

A clear finding emerged: Lack of food, specifically chinook salmon, is the orcas’ biggest threat to long-term survival, so much so that a 30 percent increase in chinook above average levels is needed to recover the orca population. That increase could be cut to 15 percent if vessel noise also is reduced by half.

Otherwise, the populations will continue to decline and there is a 25 percent chance the whales will be lost within 100 years, the scientists found.

The findings reflect the unique biology of southern-resident killer whales, which insist on targeting chinook salmon for their diet, virtually to the exclusion of other prey. They also use echolocation — sound — to find their food.

Lower abundance of salmon in a sea noisy from vessel traffic means the whales must forage longer to find their food — even as chinook populations also are declining. And if they can’t get enough to eat they burn their own fat, laden with chemicals stored in their tissue, absorbed from pollutants in the waters of the Salish Sea.

The linked nature of the threats to orcas means progress must be made on all three fronts, noted Rob Williams, an author on the paper based at Oceans Initiative in Seattle, a nonprofit scientific research firm.

The orcas already are in a 30-year population low, with just 76 animals in the J, K and L pods.

“The very first thing we should be doing is holding the line, and not increasing threats and harms that are already there, clearly we don’t want to be adding to the problem,” said Paul Paquet of the Raincoast Conservation Foundation in Sydney, B.C., a lead author on the paper.

“There is an urgency here that is not well-appreciated; they are certainly in jeopardy,” he said of the orcas. “There is no doubt about that.”

Bob Lacy, a conservation biologist with the Chicago Zoological Society, and another lead author on the paper, said the southern residents are “just holding on; the population is too fragile to withstand any increased threats.

“It is not a cheerful story, but it is a wake-up call.”

Lynne Barre, Seattle branch chief of the Protected Resources Division at NOAA Fisheries West Coast Region, said the agency is well aware of the orcas’ predicament, as their population — at the lowest numbers since the 1980s — continues to drop. They are listed as endangered under the Endangered Species Act.

“We are moving in the wrong direction,” Barre said. The agency is looking for partners at every level — local, state, federal and across the border in Canada, to ease threats to orca survival she said.

It’s not a problem orcas might just fix on their own by turning to other prey.

While so-called transient killer whales in Canada feast on marine mammals, especially seals, the southern residents will not switch from chinook — the most calories for the hunting effort of any salmon — even when the region’s most prized fish is scarce.

“It seems to be cultural, this is what they learned from their mothers, they live in tight family groups and it makes them unique and very special, but it might be a downfall as well,” Barre said.

Chinook are listed as threatened under the Endangered Species Act both in the Columbia River and in Puget Sound. Orcas forage for chinook at the mouth of the Columbia in the early spring and again in Puget Sound in the summer, especially on the west side of San Juan Island.

Scientists have been studying the whales’ foraging behavior and can see that vessel traffic affects it, she noted.

The agency is considering a proposed change in the critical habitat protected for the whales to include the West Coast all the way to the San Francisco Bay Area, to reflect what scientists are learning about how far the orcas travel for their food, Barre said.

Also under review is a protection zone that extends three-quarters of a mile offshore of San Juan Island from Mitchell Point in the north to Cattle Point in the south.

All motorized vessels would be excluded from the zone to give the whales a refuge from their noise.

The proposal from Orca Relief Citizens Alliance and other conservation groups, under review by NOAA since January, received more than 1,000 comments, including suggestions of new approaches to the problem.

James Unsworth, director of the Washington Department of Fish and Wildlife, even suggested that instead of a fixed protection zone, what is needed is a floating go-slow bubble extending 1,000 yards around every orca as it travels anywhere in Washington’s inner marine waters. Within the bubble, vessel speeds would be restricted to not more than 7 knots on the water.

That would be a big increase in the 200-yard, no-approach zone around every orca imposed by NOAA in 2011.

Slower travel speeds help orcas by quieting vessel traffic. Some change is already underway on a voluntary basis.

The Port of Vancouver, B.C., in a pilot program last summer, asked ships to cut their speed to 11 knots — a reduction to nearly half speed for some vessels — to reduce noise levels in a 16-mile-long area of the orcas’ prime feeding ground. More than 61 percent of ships using Haro Strait voluntarily participated.

It’s the kind of measure that perhaps could buy the whales some time and take the pressure off a population struggling to survive, Williams said.

“This is a really small population that is teetering.” Not because of some catastrophe, such as an oil spill, he noted, but just because of what their environment has become. “We are looking at their daily lives.”

Talk to us

More in Northwest

State Sens, Ron Muzzall, R-Whidbey Island, left, Simon Sefzik, R-Ferndale, center left, Keith Wagoner, R-Sedro-Woolley, center right, and Chris Gildon, R-Puyallup, right, confer on the floor of the Senate during a recess, Wednesday, Jan. 19, 2022, at the Capitol in Olympia, Wash. (AP Photo/Ted S. Warren)
House passes pause to state’s long-term care program and tax

The measure would delay the tax until July 2023, and would refund any premiums collected before then.

In this photo taken May 17, 2017, wine barrels are shown at a vineyard adjacent to the Walla Walla Vintners winery in Walla Walla, Wash. The remote southeastern Washington town of Walla Walla - which used to be best known for sweet onions and as home of the state penitentiary - has now reinvented itself into a center of premium wines and wine tourism. (AP Photo/Nicholas K. Geranios)
More sustainable Washington wines are on the way

Labels will indicate grape growers met guidelines in 9 areas, including water, pest and labor practices.

FILE - Washington Attorney General Bob Ferguson talks to reporters, Monday, Aug. 26, 2019, during a news conference in Seattle. In a 5-4 decision Thursday, Jan. 20, 2022, the Washington Supreme Court upheld an $18 million campaign finance penalty against the Consumer Brands Association, formerly known as the Grocery Manufacturers Association. Ferguson sued the group in 2013, alleging that it spent $11 million to oppose a ballot initiative without registering as a political committee or disclosing the source of the money. (AP Photo/Ted S. Warren)
Washington justices uphold $18M fine in GMO-labeling case

Big grocers funneled dark money into a campaign against genetically modified labels on food packaging.

Section of a tsunami high ground map. (Island County)
Tsunami warning fizzled, but future threat to Whidbey is real

State and county officials have long warned about the possibility of a tsunami striking the island.

A sign bearing the corporate logo hangs in the window of a Starbucks open only to take-away customers in this photograph taken Monday, April 26, 2021, in southeast Denver.  Starbucks is no longer requiring its U.S. workers to be vaccinated against COVID-19, reversing a policy it announced earlier this month. The Seattle coffee giant says, Wednesday, Jan. 19, 2022,  it's responding to last week’s ruling by the U.S. Supreme Court.  (AP Photo/David Zalubowski)
Starbucks nixes vaccine mandate after Supreme Court ruling

The move reverses a policy the coffee company announced earlier this month.

Marianne Edain and Steve Erickson of WEAN at their South Whidbey home in 2019. (Laura Guido / South Whidbey Record, file)
Whidbey environment group isn’t suing county for first time in 25 years

The impact WEAN founders have had on environmental policy in Island County is extensive.

Lawsuit: Washington’s new majority Latino district is a ‘facade’

The legal action targets state Legislative District 15 in Yakima.

FILE - Trees scorched by the Caldor Fire smolder in the Eldorado National Forest, Calif., Friday, Sept. 3, 2021. The Biden administration wants to thin more forests and use prescribed burns to reduce catastrophic wildfires as climate changes makes blazes more intense. (AP Photo/Jae C. Hong, File)
US plans $50B wildfire fight where forests meet suburbia

Blazes have wiped out communities in California, Colorado, Arizona, Oregon and Washington state.

Skiers make their way uphill under idle lift chairs at the Summit at Snoqualmie Ski Area as fresh snow falls, Wednesday, Feb. 14, 2018, in Snoqualmie Pass, Wash. Several inches of snow fell Wednesday, and the area shown was scheduled to open to skiers and begin lift operation later in the day. (AP Photo/Ted S. Warren)
Snoqualmie ski resort cuts some operations after losing power

For Monday skiing, the resort’s website said they have “less than a partial supply of energy.”

Most Read