Orcas hunting for salmon: Not worth the effort in Puget Sound?

Trying to understand what motivates Puget Sound’s killer whales is difficult enough when the orcas are nearby. But now that they have abandoned their summer home — at least for this year — researchers are not able to easily study their behaviors, their food supply or their individual body conditions.

L-84, a 29-year-old male named Nyssa, was thought to be in good health when he went missing.
Photo: Center for Whale Research

Not so many years ago, we could expect the orcas to show up in the San Juan Islands in May, presumably to feast on spring chinook returning to the Fraser River in British Columbia and to streams in northern Puget Sound. Those chinook have dwindled in number, along with other populations of chinook in the Salish Sea, so it appears that the orcas may not come back at all.

Apparently, they have decided that it isn’t worth their time and effort to set up a summer home in the inland waterway. They have gone to look for food elsewhere, such as off the west coast of Vancouver Island, where it is harder for researchers to tell what they are eating and exactly where they are going.

The whales were out there somewhere this past week when Ken Balcomb of the Center for Whale Research announced that three whales had been missing long enough to declare them deceased. He had been consulting with experts and observers in Canada. See my Water Ways post from Tuesday.

Food is the big issue for the southern resident killer whales. They have been judged to be in overall worse body condition than the northern residents — an entirely separate group that normally stays farther up the coast in British Columbia. Experts are reporting that the northern residents have been venturing south more often than they used to. Perhaps the cultural divide between the two resident groups has begun to weaken.

It’s all in the realm of speculation, of course. Last year, I shared some ruminations about what could have happened if the endangered southern residents had not grown up in a culture of eating chinook salmon. I mentioned some interesting research papers on the topic. See Water Ways, Aug. 30, 2018.

Food is the key. Despite other problems that humans have caused — including toxic chemicals, noise and general disruption — food is at the heart of the matter. When you are hungry and searching for food, you don’t have much time for social interaction — and making babies takes a back seat to survival.

Even when southern resident females do get pregnant, they suffer a high rate of miscarriage, often coming late in pregnancy. Food and stress are related to these problems, according to research by Sam Wasser, director of the Center for Conservation Biology whose work I reported in the Encyclopedia of Puget Sound in 2016.

Although the term “starvation” is often tossed around loosely, few if any of the dead whales are actually starving to death from lack of available food. They may have stopped eating when they got sick or for some other reason. Illness can be brought on by a weakened condition in conjunction with reduced immunity caused by toxic chemicals in their food. It’s more complex than “starvation,” as writer Jeff Rice of the Puget Sound Institute points out in a new story posted in the Encyclopedia of Puget Sound.

A low reproductive rate and unexpected deaths continue to drive the population downward. Some deaths can be predicted when the whales loose so much body fat that they reach a condition called “peanut head,” but other deaths come quickly and unexpectedly.

“We had expected two of the three deaths, having chronicled their decline during the past year,” Ken Balcomb said in an email on Friday. “But L84’s death was unexpected. He was a vibrant male who appeared healthy.”

When apparently healthy whales disappear, experts are left wondering what happened. Years ago, this kind of sudden disappearance was more typical of their final departures, because the whales were in better condition. Other factors, such as ship strikes and Navy operations were sometimes suspected, and disease is always a lurking threat.

Finding ways to improve the chinook runs should help the whales, and that effort continues despite some disagreement about how to go about it. But larger forces are also at play, such as long-term shifts in ocean conditions and changes in the climate that reverberate through the entire food web.

Laura Blackmore, executive director of Puget Sound Partnership, issued a statement Thursday that reflects what many Northwest residents may be feeling.

“We are deeply saddened to learn of the presumed deaths of three endangered southern resident orcas, L84, K25, and J17,” Laura wrote. “These new losses cut deeply, and we grieve with all those who mourn these symbols of Puget Sound.

“Our orcas are dying because the marine environment they live in is ailing and there are too few salmon for them to eat,” she continued.

“The Puget Sound Partnership stands with Governor Inslee, the governor’s Southern Resident Orca Task Force, and the many tribes, government agencies, organizations, businesses and individuals who are committed to helping recover the orca population. Together, we can help by restoring salmon runs, quieting the waters of Puget Sound, and getting toxic chemicals out of our waterways.”

New government policies and laws are being implemented, she said. Meanwhile, there are some things that we all can do. Here are her suggestions for individual action:

  • Help restore salmon runs. Volunteer on a habitat restoration project. See orca.wa.gov for links to organizations involved in habitat restoration.
  • Quiet the waters of Puget Sound. If you’re a boater, give orcas space. Follow the BeWhaleWise guidelines for whale watching.
  • Keep toxic chemicals out of our waterways. Stop using toxic chemicals in your home or on your landscape; fix vehicle leaks; and have your vehicle oil changed by a professional.
  • Learn about southern resident orcas, and pass the information on to others.
  • Speak up for orcas. Vote. Make sure your local, state, and federal representatives know how important orcas are to you.

One thought on “Orcas hunting for salmon: Not worth the effort in Puget Sound?

  1. Applying the research to the field and honing the question to “what needs to be done to help the SRKW survive? the weight of the evidence says food shortages are impacting them disproportionately relative to either transients or NRs. I think that’s a safe enough assumption to commence immediate action to actually help them survive.

    Continuing down that process, it seems logical to look for the fastest possible ways to increase salmon presence within the SRKW’s known range. Dramatic hatchery increases have been proposed but there’s not a lot of margin for that scale of increase, especially if avoiding negative impacts on native salmon populations is considered. Wholesale predator culling also has limited prospects of preventing predation on the scale needed to provide substantially more Chinook or other fish that SRs eat without seriously depleting the prey base for transients.

    Myriad salmon habitat restoration projects, if funded above the 20% level currently appropriated, could substantially increase their overall food supply gradually over the next few decades.

    If access could be substantially improved for high-altitude spring/summer Chinook to and from the 5,500 miles of spawning streams in the Salmon and Clearwater basins upriver of the reservoirs that span most of the 140 miles of the Snake above the confluence with the Columbia, substantially more smolts would survive to the Pacific, and adults to the spawning beds, to increase the SRKW food supply by at least several hundred thousand adult fall, spring, and summer Chinook beginning within 3 years, greatly reducing their risk of suffering nutritional deficiency.

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