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In 1971, the United States conducted its largest underground nuclear weapons test on a remote Alaskan island.
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Earlier, scientists managed to relocate hundreds of sea otters that may have died in the explosion.
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Their populations are thriving in Alaska, Canada, and Washington, but they cause some problems.
When a large earthquake struck Alaska’s Aleutian Islands in 2014, U.S. government scientists rushed to assess the damage on Amchitka Island. were looking radiation leak of underground nuclear tests carried out decades earlier.
During the first half of the 20th century, the remote island had been a wildlife reserve, until the United States government converted it into a nuclear test site.
Three atomic weapons exploded in Amchitka in the late 1960s and early 1970s, including the largest underground detonation the United States had ever set off.
No humans lived on the island, but the largest explosion, in 1971, killed at least 900 sea otters. He Atomic Energy Commissionthe government agency in charge of nuclear research, had predicted at most 240 the otters would die.
Had environmentalists and others not pushed to relocate some otters before the detonation, it likely would have been much worse.
“There was pressure from the state of Alaska as well as environmental groups,” conservation biologist and author Joe Roman told Business Insider. “They ended up moving hundreds of otters.”
Roman wrote about the otter relocation in his new book “Eat, Poop, Die: How Animals Make Our World“.
Why were the otters collected?
When the AEC was studying Amchitka in the 1960s, the island’s sea otter population was one of the few that had survived the near-extinction of marine mammals a century earlier.
Their delicious skins were valued as “soft gold.” In the 1700s and 1800s, hunters killed about a million sea otters to sell their skin.
The population drop was alarming, from between 150,000 and 300,000 at the beginning of the 18th century to around 2,000 just 200 years later. Russia, Japan, Great Britain and the United States signed a fur treaty to help protect the animals in 1911. Over the next few decades, sea otter numbers increased to around 30,000.
In 1959, the charismatic animals starred in a nature film, “Amchitka Sea Otters“No one wanted to see those adorable otters decimated by an underground explosion, John Vania, an otter specialist with the Alaska Department of Fish and Game, told AEC.
A confluence of events made many Americans more environmentally conscious in the 1960s, from the The Cuyahoga River is constantly on fire to Rachel Carson’s exploration of the dangers of pesticides in his book “Silent Spring” to the greatest Oil spill in US waters at the time, near Santa Barbara, California.
The protesters did not want a third nuclear test in Amchitka at all. In fact, the conservation group Greenpeace was formed from an organization trying to stop the test.
A U.S. Fish and Wildlife Service biologist, Karl Kenyon, had already worked to relocate some otters to areas where they had lived before the 18th-century hunt. The explosions in Amchitka were a good reason to move even further, ecologists and biologists thought.
If the AEC paid for it, Vania said, scientists could relocate the otters.
The return of the kelp forests
In addition to financing the transfer, the AEC provided the scientists with a plane with capacity for more than 50 otters. Over the next few years, scientists captured more than 700 otters in nets and transported them to southeastern Alaska, Washington, Oregon, and British Columbia.
Over the next 50 years, sea otter populations in many of these places, such as Sitka, Alaska, would grow from several dozen to hundreds or thousands. “All the sea otters, of which there are thousands, in Sitka are now descendants of these airborne sea otters,” Roman said.
Eighty-nine otters went to British Columbia. Now there are more than 7,000. An estimate 125,000 sea otters They live in the Pacific Ocean as of 2015.
The presence of otters soon changed the landscapes where they live today. Their relocation allowed biologist Jim Estes to study islands with and without otters. As a result, he realized that there was a link between otters, sea urchins and kelp forests.
“In the absence of sea otters, there are a lot of sea urchins,” Roman said. “When there are many urchins, they create what are called wasteland hedgehogs.”
Sea urchins eat the algae supports that anchor the algae. Roman compares it to cutting down a forest. The algae eventually disappear.
One of otters’ favorite foods is sea urchin. And they can eat a lot of them. “They have a very high metabolism,” Roman said. “They’re eating machines.” When the number of sea urchins decreases, the seaweed returns.
In Sitka Sound, sea otters reduced the sea urchin population by 99%. In return, the kelp forests exploded.
“Forests provide food and shelter for more than 800 species, including sea lions, harbor seals, lingcods, gobies, moray eels, octopuses, crabs, sea anemones and starfish,” Roman wrote.
Kelp forests are also amazing at capturing carbon, a concern for global warming.
Otters can also affect land animals, Roman wrote, either directly, as food for wolves on Alaska’s Pleasant Island, or indirectly, with kelp forests that attracted fish-eating birds.
Racing with otters
Roman called the sea otter relocation one of the “most successful cases” of its kind. However, he said, “you don’t release animals that way these days.”
For one, the United States did not consult First Nations and Indigenous peoples before releasing the otters. The mammals reclaimed the kelp forests, but destroyed a reliable source of food for many people.
“Sea otters don’t just eat urchins,” Roman said. “They also eat geoducks and other valuable benthic invertebrates in the area.” That includes crabs and clams. “And, of course, that puts them in conflict with the fishermen in that area,” he said.
Suddenly, otters appeared where they had not been for generations. “So no one remembers having sea otters in that area,” Roman said. “They are used to collecting these invertebrates and they are quite abundant in the absence of a predator.”
Their voracious appetite is one of the reasons some people call otters “sea rats“For some Alaskans and Canadians, they are seen as a nuisance.
When otters arrived in new regions of Alaska, Washington and Oregon in the 1960s and 1970s, it was still legal to hunt them. The Marine Mammal Protection Act of 1973 changed that, although Alaska Natives can still hunt otters, whales and seals.
“I talked to Mike Miller, who is a Sitkan native,” Roman said. “He promotes this idea of some balance” between the human population and the otters.
It is an idea that researchers also echo. “We’re wondering if there’s a sweet spot where you can have it all,” says environmentalist Kristy Kroeker. he told the BBC.
While sea otter numbers are much higher than 100 years ago, the animals still endangered. They also face challenges due to the climate crisis. And not all relocated populations survived. They disappeared from Oregon after about a decade.
But the success of sea otters elsewhere (especially their impact on kelp forests) has made Oregon want try to reintroduce them again, only with more caution and this time with the contribution of the coastal tribes.
Read the original article on Business Insider
