Southern resident orca pod in best condition in decade
Published Monday, May 10, 2021 11:25AM PDT
SEATTLE -- She was a mother who happened to be an orca, whose plight resonated around the world as she clung to her dead calf, refusing to let it go.
Mother orca Tahlequah, J35, brought front and centre the extinction crisis threatening the southern resident killer whales that frequent Puget Sound. There are only 75 left.
She swam through the Salish Sea for 17 days and more than 1,000 miles in the summer of 2018, in what many interpreted as a journey of grief. It's possible she never let the calf go; when it was last photographed by scientists at the Center for Whale Research, the calf was falling apart.
But on this Mother's Day, there is some cause for cautious optimism for some of the most famous mothers in our region, on whom the future of this fragile population of orcas depends.
Since Tahlequah lost her calf that lived only one half-hour, she has birthed another, J57, a male born in September 2020 - and still going strong. Two more calves also have been born to J pod, J56, a female born in 2019, and J58, a female born in 2020.
“There are signs for optimism; in general over the last several years J pod is in better condition than in much of the last decade,” John Durban, professor at Oregon State University told The Seattle Times. He's also a research associate with an orca health monitoring project led by Holly Fearnbach of SR3, a science and research and marine mammal rescue non-profit.
Using a drone flown more than 100 feet above the whales, they take photographs to document the orcas' body condition. And lately, what they are seeing in J pod generally is improvement.
“There is hope in our images,” Durban said. “But it is fragile.”
After all, the region was celebrating a baby boom of southern residents in 2015 with five births - but three of those calves and two of the mothers subsequently died.
By the summer of 2018, J50, not even 4 years old, was wasting away, spurring an attempt at an international rescue effort, even as mother orca Tahlequah was clinging to her dead calf.
But since then a birth to L pod, L124 born in May 2019, and L125, born in February 2021, as well as the three J pod calves, have given the region something to root for: not only the new orca babies, but also their moms.
To a greater degree than in many other animals, including humans, the southern resident orcas put family first. Their society is matriarchal, with the pods led by grandmothers and mothers.
Every baby brings both hope and risk for the population, as the mother undergoes the most costly and risky stage of her life, carrying, birthing and nursing her baby.
Published peer-reviewed research led by Sam Wasser at the Center for Conservation Biology at the University of Washington has found two thirds of southern resident orca pregnancies are lost because of nutritional stress.
The southern residents eat primarily chinook salmon, which mostly are in decline throughout the orcas' foraging range.
The sharing never stops; orca moms care for their young lifelong.
When adult male orcas lose their mother their own chances at survival are diminished. “He has a higher chance of mortality, even in the prime of life,” Durban said. “Some of that may be emotional, but it is also direct for support from their mothers they are dependent on.”
Orca society is one of the few animal communities on Earth, in addition to humans, in which mothers persist decades into their post-reproductive years. These grandmother orcas play a crucial role in the pods, with the ecological knowledge they carry of where to find fish, particularly when times are lean.
L25 is the oldest orca grandmother left. Durban and Fearnbach last photographed her last September. In 2019, she also was photographed by whale watchers all the way down south of San Francisco - where she had taken her family to fish for chinook.
Born in about 1928, L25 learned the foraging routes of the southern residents from her grandmother - in a time before many of the major dams in the Northwest were built and the Columbia and Lower Snake rivers were still free flowing - and when winter chinook, unique in the world, were still abundant in California's Sacramento River.
She knew an environment of cleaner, quieter, more abundant waters.
L25, J35 and the other orca grandmothers and mothers still work to feed their extended families, now in a vastly changed world.
Today two of the 10 most endangered animals protected by the National Oceanic and Atmospheric Administration are the southern resident orcas and California winter chinook. Twin monarchs, in a struggle for survival.
Yet there is hope.
“We are encouraged that in the last two years J pod has in general been in better body condition than over much of the last decade,” Durban said. “We hope it continues and these calves can thrive. Every calf counts in a population this small.”