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Facing the Possibility of Extinction for
by Christopher Dunagan
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Southern Resident killer whales, cherished by many Puget Sound residents, are on a course headed for extinction, and they could enter a death spiral in the not-so-distant future.
It is time that people face this harsh reality, Ken Balcomb told me, as we discussed the latest death among the three pods of orcas. A 2-year-old male orca designated J-52 and known as Sonic died tragically about two weeks ago.
The young orca was last seen in emaciated condition, barely surfacing and hanging onto life near the entrance to the Strait of Juan de Fuca on Sept. 15. Ken, director of the Center for Whale Research, said the young whale was attended to by his mother Alki, or J-36, along with a male orca, L-85, known as Mystery -- who may have been Sonic's father, but more about that later.
Extinction, Ken told me, is "very real" -- not some ploy to obtain research dollars. The population of endangered Southern Residents has now dropped to 76 -- the lowest level since 1984. Most experts agree that a shortage of chinook salmon -- the primary prey of the orcas -- is the greatest problem facing the whales.
Last week, the Leadership Council -- the governing body of the Puget Sound Partnership -- discussed what role the partnership should play to "accelerate and amplify efforts" to restore chinook salmon runs and save the orcas. Chinook themselves are listed as a threatened species.
Puget Sound Partnership is charged by the Legislature with coordinating the restoration of Puget Sound, including the recovery of fish and wildlife populations.
The Leadership Council delayed action on a formal resolution (PDF 149 kb.) in order to allow its staff time to identify specific actions that could be taken. Although the resolution contains the right language, it is not enough for the council to merely show support for an idea, said Council Chairman Jay Manning.
Sonic was one of the whales born during the much-acclaimed "baby boom" from late 2014 through 2015. With his death, three of the six whales born in J pod during that period have now died. No new calves have been born in any of the Southern Resident pods in nearly a year.
Meanwhile, two orca moms -- 23-year-old Polaris (J-28) and 42-year-old Samish (J-14) -- died near the end of 2016. Those deaths were followed by the loss of Granny (J-2), the J-pod matriarch said to have lived more than a century. Another death was that of Doublestuf, an 18-year-old male who died last December.
Three orcas were born in L pod during the baby boom, and none of those whales has been reported missing so far.
Ken believes he witnessed the final hours of life for young Sonic, who was lethargic and barely surfacing as the sun set on the evening of Sept. 15. Two adults -- Sonic's mother and Mystery -- were the only orcas present, while the rest of J pod foraged about five miles away.
That was the last time anyone saw Sonic, although his mother Alki as well as Mystery were back with J pod during the next observation four days later. Ken reported that Alki seemed distressed, as often happens when a mother loses an offspring.
Ken admits that he is speculating when he says that Mystery may have been Sonic's father. It makes for a good story, but there could be other reasons why the older male stayed with the mother and calf. Still, researchers are engaged in studies that point to the idea that mature killer whales may actually choose a mate rather than engaging in random encounters. I'm looking forward to the upcoming report.
I must admit that this issue of extinction has been creeping up on me, and it's not something that anyone wants to face. Food is the big issue, and chinook salmon have been in short supply of late. It will be worth watching as the whales forage on chum salmon, as they are known to do in the fall months.
"This population cannot survive without food year-round," Ken wrote in a news release. "Individuals metabolize their toxic blubber and body fats when they do not get enough to eat to sustain their bodies and their babies. Your diet doctor can advise you about that.
"All indications (population number, foraging spread, days of occurrence in the Salish Sea, body condition, and live birth rate/neonate survival) are pointing toward a predator population that is prey-limited and nonviable," he added.
The Center for Biological Diversity, which was involved in the initial lawsuit that led to the endangered listing for the whales, is calling upon the NOAA's National Marine Fisheries Service to move quickly to protect orca habitat along the coasts of Washington, Oregon and California. Currently designated critical habitat is limited to Puget Sound, even though the whales are known to roam widely along the coast.
"The death of another killer whale puts this iconic population on a dangerous path toward extinction," Catherine Kilduff of CBD said in a news release. "If these whales are going to survive, we need to move quickly. Five years from now, it may be too late."
How fast the whales will go extinct is hard to determine, experts say, but the current population is headed downward at an alarming rate, no matter how one analyzes the problem.
"I would say we are already in a very dangerous situation," said Lance Barrett-Lennard, senior marine mammal researcher at the Vancouver Aquarium. "If this trajectory continues and we lose two or three more from deaths or unsuccessful birth, we will be in a real spiral," he told reporter Richard Watts of the Times Colonist in Victoria, B.C.
A five-year status review (PDF 4.3 mb), completed last December by NMFS, takes into account the number of reproductive males and females among the Southern Residents, the reproductive rates, and the ratio of female to male births (more males are being born). As the population declines, the risk of inbreeding -- and even more reproductive problems -- can result.
Eric Ward of NOAA, who helped write the status report, said the agency often estimates an extinction risk for endangered populations, but the actual number of Southern Residents is too small to produce a reliable number. Too many things can happen to speed up the race toward extinction, but it is clear that the population will continue to decline unless something changes.
As Ken describes it in simple terms, Southern Resident females should be capable of producing an offspring every three years. With 27 reproductive females, we should be seeing nine new babies each year. In reality, the average female produces one offspring every nine years, which is just three per year for all three pods. That is not enough to keep up with the death rate in recent years. To make things worse, reproductive females have been dying long before their time -- and before they can help boost the population.
Experts talk about "quasi-extinction," a future time when the number of Southern Residents reaches perhaps 30 animals, at which point the population is too small to recover no matter what happens. Some say the population is now on the edge of a death spiral, which may require heroic actions to push the population back onto a recovery course.
As described in the five-year status review, prey shortage is not the only problem confronting the Southern Residents. The animals are known to contain high levels of toxic chemicals, which can affect their immune systems and overall health as well as their reproductive rates. Vessel noise can make it harder for them to find fish to eat. On top of those problems is the constant threat of a major oil spill, which could kill enough orcas to take the population down to a nonviable number.
Despite the uncertainties, Robert Lacey of Chicago Zoological Society and his associates calculated in 2015 that under recent conditions the Southern Resident population faces a 9 percent chance of falling to the quasi-extinction level within 100 years. Worsening conditions could send that rate into a tailspin. See report for Raincoast Conservation Foundation.
What I found most informative was how the probability of extinction changes dramatically with food supply. (See the second graph on this page.) A 10 percent decline in chinook salmon raises the quasi-extinction risk from 9 percent to 73 percent, and a 20 percent decline raises the risk to more than 99 percent.
On the other hand, if chinook numbers can be increased by 20 percent, the whales would increase their population at a rate that would ensure the population's survival, all other things being equal. Two additional lines on the graph represent a gradual decline of chinook as a result of climate change over the next 100 years -- a condition that also poses dangerous risks to the orca population.
The close links between food supply and reproductive success are explored in a story I wrote last year for the Encyclopedia of Puget Sound.
At last Wednesday's Puget Sound Leadership Council meeting, members discussed a etter from the Strait (of Juan de Fuca) Ecosystem Recovery Network (lPDF 146 kb) that called on the Puget Sound Partnership to become engaged in salmon recovery efforts outside of Puget Sound -- namely the Klamath, Fraser and Columbia/Snake river basins.
"Such collaborative efforts must be done for the benefit of both the SRKW and chinook fish populations, without losing sight of the continuing need to maintain and improve the genetic diversity of these fish populations ..." states the letter.
A separate letter from the Puget Sound Salmon Recovery Council (PDF 395 kb) also asks the Puget Sound Partnership to become more engaged in orca recovery. The group is calling on the partnership to support salmon recovery statewide, "relying on each region to identify strategies to restore robust salmon runs."
Rein Attemann of Washington Environmental Council said salmon on the Columbia and Snake rivers, as well as he Fraser River in British Columbia, are "vitally important" to the recovery of the Southern Resident killer whales, and Puget Sound efforts should be coordinated with other programs.
Jim Waddell, a retired civil engineer with the Army Corps of Engineers, spoke forcefully about the need to save chinook salmon and the Southern Residents, starting by tearing down dams on the Snake River.
"We are out of time," Waddell said. "The Corps of Engineers have it within their power to begin breaching the dams within months.... The orcas cannot survive without those chinook."
An environmental impact statement on chinook recovery includes the option of breaching the dams, something that could be pushed forward quickly, he said.
"Breaching the Snake River dams is the only possibility of recovery," Waddell said. "There is nothing left."
Stephanie Solien, a member of the Leadership Council, said speaking up for orcas in the fashion proposed is not something the council has done before, but "we do have a responsibility to these amazing animals and to the chinook and to the tribes."
The council should work out a strategy of action before moving forward, she added, but "we better get to moving on it."
Related Pages:
Another Orca from 'Baby Boom' Dies, Fears Expressed about Extinction by Staff, KOMO News, 9/25/17
Why Do Most Orca Pregnancies End in Miscarriage? Look Upstream by Hanna Brooks Olsen, Pacific Standard, 9/21/17
UW Professor's Study Links Food Scarcity to Orcas' Failed Pregnancies by Lynda Mapes, Seattle Times, 6/28/17
Southern Resident Killer Whale Population is Running Out of Salmon, Running Out of Time by Carl Safina,National Geographic, 1/31/17
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