Feed starving whales farmed salmon, say scientists
Radical idea that led to an orphaned orca being returned to the wild could help endangered Southern Resident Killer Whales.
By Fabian Dawson
One of the most enduring tales of human intervention to save killer whales is that of Springer, found emaciated in Puget Sound, rescued and restored to health, before being returned to her orca family in the waters off Northern Vancouver Island.
Since her historic reintegration into the wild in 2002, Springer aka A73, has been seen with her Northern Resident Killer Whale family living a normal life after giving birth to two healthy offspring.
One part of the remarkable story that went untold, was what nourished Springer back to health.
It was a diet of omega-3-rich farmed Atlantic salmon, said Dr. Wally Pereyra, a globally renowned scientist who has been involved with Pacific Northwest fisheries for over 50 years.
Now as Springer’s cousins collectively known as the Southern Resident Killer Whales (SRKW) face imminent threats to their survival, Dr Pereyra believes that a lipid-rich farm-raised salmon supplemental feeding program will help the ailing orcas.
There are only 73 Southern Resident Killer Whales now and conservationists say they are on a collision course with extinction mainly because of declines of their primary prey, Chinook salmon. The known range of the Southern Resident Killer Whale, which are also threatened by contaminants extends from southeastern Alaska to British Columbia down to central California.
Efforts are underway on both sides of the border to save the whales, which include boosting hatchery production of Chinook salmon, habitat restoration and sweeping closures of commercial and recreational fisheries around Vancouver Island.
In Seattle, the Wild Fish Conservancy (WFC) is seeking an injunction to stop the Southeast Alaska summer troll fishery, alleging the government has failed to allow enough King (Chinook) salmon to return to Puget Sound to feed endangered Southern Resident Killer Whales.
Dr. Pereyra’s suggestion of feeding the whales with farmed salmon, comes in the wake of the lawsuit and Canada’s decision to continue closures for recreational and commercial fishing in key killer whale foraging areas.
“I have been known to think outside the box,” said the retired NOAA (National Oceanic and Atmospheric Administration) scientist, who acts as an advisor to government agencies, international private sector joint-ventures and conservancy groups.
In a direct challenge to WFC, Dr. Pereyra said: “If you really want to help the whale population, please consider withdrawing your lawsuit and preliminary injunction request, and instead work with all stakeholders to increase hatchery Chinook production; restore riparian habitats and reduce ecosystem degradation; and immediately initiate a SRKW supplemental feeding program of lipid-rich farm-raised salmon.”
Dr. Pereyra in an opinion piece released via the Northwest Aquaculture Alliance (NWAA) said
WFC should support measures to provide farm-reared lipid-rich salmon to SRKW populations. “Such a feeding program is needed to alleviate a short-term extinction risk while other longer-term programs to increase natural and hatchery production of Chinook salmon prey for the SRKW are identified and implemented.
“Additionally, the WFC makes a big issue out of the delay in implementation of proposed mitigation measures to increase hatchery production of Chinook salmon. This concern on their part should elicit whole-hearted support from them to initiate an immediate program to implement a directed feeding program with lipid-rich salmon.
“Taking legal action to shut down a scientifically managed and authorized troll salmon fishery will do little or nothing for the endangered SRKW but will certainly economically damage family fishermen and their small coastal communities.”
So how can this be done?
Dr. Pereyra said while the idea may seem radical, it has been raised before and that science supports it while technology is available to implement it.
Speaking to SeaWestNews, Dr. Pereyra said behavioral studies show whales, like other animals, can be conditioned to be attracted to feeding sources.
“If you feed them consistently for a while in a similar pattern, they will be attracted to the food source…they will eat more, get healthier and reproduce.
“When the numbers are sufficiently high, this feeding routine can stop and the whales will reacclimatize to foraging in the wild.”
“You could use well boats to deliver the farmed fish to where the whales feed.”
On concerns that farmed salmon being released in the whales’ foraging areas could do damage to native fish stocks, Dr. Pereyra said millions of Atlantic salmon have been intentionally released into the wild in dozens of experiments over the years.
“They have not been able to take to this environment and colonize,” he said.
Agreed, Dr. Conrad Mahnken, the former director of the U.S. National Marine Fisheries Service, Manchester Field Station in Washington where Springer, the orphaned orca, was fed and treated in 2002.
Recalling the event that made headlines around the world, Dr. Mahnken said money was quickly running out to feed Springer a special diet after she was moved to a sea pen at the government research station in Manchester.
“Fortunately, the local fish farmers stepped up to provide salmon for Springer,” he told SeaWestNews.
Both farmed Atlantics and most Chinook salmon share a similar lipid profile so feeding Springer farmed Atlantics was obviously a suitable Chinook salmon substitute for the scientists at the government research centre.
To avoid creating a dependency on humans, staff kept their contact with Springer to a minimum and released food into her pen at random times of day. Her health improved and she began to eat more, approaching the 60–80 pounds of fish per day needed to increase her weight. After medical tests revealed no genetic disorders or communicable diseases, Springer was cleared for her return to Canada.
Dr. Mahnken is supportive of Dr. Pereyra’s suggestion of feeding the endangered SRKW farmed salmon.
“Lawsuits by conservation groups don’t do anything for the whales…this is an idea worth pursuing” he said.
Jeanne McKnight, Executive Director of Northwest Aquaculture Alliance, said the lawsuit by the Wild Fish Conservancy, if successful, will effectively prevent Chinook salmon fishing in Southeast Alaska and adversely impact the fate of some 1,600 Southeast Alaska salmon trollers.
“Similarly, in Canada, the recreational and commercial fisheries closures have had devastating impacts to rural fishermen, their families, and coastal communities.”
McKnight urged conservation groups to be part of the solution and work with all stakeholders to help the whales.
“Frivolous lawsuits don’t do that,” said McKnight, whose association represents companies that farm as well as commercially harvest seafood.
Main image: A Southern Resident Killer Whale pod (NOAA)