How to save orcas living in the south

This summer, a baby killer whale is swimming in the waters of the Salish Sea (inland marine waters along Washington state and British Columbia) for the first time since 2011. The birth of a new baby whale is cause for celebration among struggling residents for decades.

But the calf alone isn’t enough to allay the concerns of researchers and conservation groups southern resident killer whales, as the genetically distinct subgroup of species found in those waterways are called. For one thing, the first year will be the hardest for a calf to survive. Health indicators such as stress hormone levels and body weight across the orca population indicate that successful births are becoming increasingly rare.

“[The new calf] “It’s pretty miraculous,” says Deborah Giles, director of science and research at the Washington-based Wild Orca Group. “But we know from decades past that these females were able to give birth every three years, which is not the case now.”

[Related: Drones revealed the intricate social lives of these killer whales]

In 2017, Giles’ team found that 69 percent of the pregnancies of female resident whales in the South did not terminate in recent years. Due to chronic stress and malnutrition, the population of these killer whales has shrunk from 89 individuals when they were federally listed as critically endangered in 2005 to just 74 today.

Killer whales face the same set of threats they did 17 years ago: noise and potential collisions with boats, chemical pollutants, and a lack of prey. Of all of these, researchers today are most concerned about the shortage of orca’s main food source, chinook salmon.

These killer whales co-evolved with the Chinook, which is also an endangered species. They can and do eat other types of fish, but the bigger and fatter fish of the Salish Sea have always made up the majority of their diet.

With the number and size of salmon returning to breed in the Washington and British Columbia rivers dwindling over the years thanks to overfishing, rising water temperatures, clogging dams, and habitat destruction, among other things, killer whales have struggled to find enough prey to survive.

“They’re starving all the time because there aren’t enough fish out there,” Giles says.

Another recent study of southern resident killer whales by researchers at the University of British Columbia identified the same problem. By comparing the decades’ availability of salmon with what they know about the whales’ movements and health, they determined that for six of the past 40 years, marine mammals haven’t been getting enough to eat.

This means that any effort to protect endangered killer whales in the south must include protecting the endangered Chinook salmon. “The most promising effort toward promoting a positive pathway to the recovery of southern-dwelling killer whales are salmon and river recovery initiatives throughout the entire whale population,” says Shari Tarantino, executive director of the Washington-based nonprofit Orca Conservancy.

[Related: The secret to saving salmon is lodged in their ears]

The state has introduced new regulations this summer that require whale-watching boats to keep a half-nautical mile away from orcas, following news that a number of them are pregnant, but potentially unhealthy. While these additional restrictions will benefit the whales, Giles of Wild Orca says they won’t do enough on their own to help them recover in the long run. We have spent a lot of time studying the effects of ships to reduce the impact of ships on these animals. Now, we need to look at policies focused on fisheries management, she says.

Tarantino, of the Orca Conservancy, agrees. “While we support mitigation efforts, emergency regulations in Washington state still fall short of what the southern killer whale population needs,” she adds.

And it’s about more than just orcas. Killer whales are at the top of the food chain, and as Tarantino points out, “When an apex predator fails, it means that the entire ecosystem below it also fails, which will ultimately affect the population.”

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