Senin, 02 November 2020

Will Oregon see sea otters again? - OPB News

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Ron Jameson returns to Cobble Beach at Yaquina Head, holds up his binoculars, and scans the horizon.

Above the constant roar of surf and clatter of the beach’s pebbles, the air is filled with a cacophony of Caspian terns, the croaks of cormorants, and the incessant barking of California sea lions, punctuated by the shrill cry of seagulls. In the distance, Jameson spots the heads of harbor seals bobbing in the waves. Jameson’s eyes are scanning for an animal that’s not there: sea otters.

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A retired federal biologist, Jameson did research on sea otters for over 30 years.

When he scans the ocean, an image from nearly 50 years ago comes back in his memory: the sight of sea otters here on Oregon’s coast. Jameson was witness to an exciting moment in Oregon history — a massive attempt, unlike any other, to reestablish a population of sea otters on the Oregon Coast.

That chapter ended nearly 40 years ago, when the marine mammals mysteriously vanished.

Today, there is a renewed interest in bringing sea otters back to the Oregon Coast, layered with the lingering failure of the past. Researchers now wonder if we’ve learned enough to make a second attempt.

Luxurious fur, near extinction

Sea otters once called Oregon home, part of a larger connected population of sea otters spanning the entire length of the Pacific coast, as far north as Aleutian Islands in Alaska, and as far south as Baja, Mexico.

With a million hairs per inch, sea otters have the densest fur of any mammal. The plush pelts were esteemed by native communities as symbols of luxury and status.

During the fur trade era of the 18th and 19th centuries, sea otter pelts became an international commodity, fetching top dollar.

The last wild sea otter in Oregon was reported killed in 1906. Its pelt was sold in San Francisco for $900. Just four years later, in 1910, the last wild sea otter in Washington was killed. Its pelt sold for $1,000, approximately $27,000 today.

Related: Bringing back Oregon's sea otters gets federal bucks for feasibility study

The first protection of sea otters was passed in 1911, under the international Fur Seal Treaty. But by then, possibly less than 1,000 sea otters survived in the world. Only a very few pockets in the most remote places remained.

“By that time, sea otters no longer occurred anywhere outside the Aleutians or Prince William Sound, Alaska, and a tiny remnant population in California,” said Jameson. “None in Washington, none in Oregon, none in British Columbia. They were gone.”

The largest group of wild sea otters had survived in the remote Aleutians Islands. Shortly after the passage of the Fur Seal Treaty, the Aleutian Islands National Wildlife Refuge was established in 1913. It might have seemed that sea otters would once again be left alone, safeguarded from human disturbance.

Their respite would not last long.

A fishing boat tows a holding pen of wild sea otters captured in Alaska for the reintroduction attempt in 1970.

A fishing boat tows a holding pen of wild sea otters captured in Alaska for the reintroduction attempt in 1970.

Oregon Game Commission

Nuclear bombs and otters on planes

The Aleutian Islands are about as remote as it gets—a string of small, rock-and-tundra islands like tiny dots in the Bering Sea. They stretch from Alaska nearly to Russia. They are wind-swept and frigid.

Amchitka, the southernmost link of the Aleutian Island chain, had lost its native Aleut population in the 19th century. During World War II, the United States built an airfield to counter an invasion by Japanese forces. Since then, the remote island had been left to the wildlife, including the surviving sea otters.

At the height of the Cold War, the Atomic Energy Commission wanted to test America’s newest, most powerful nuclear bombs. Atomic bombs had already been tested on the U.S. mainland, as well as the Marshall Islands. But these sites had people living near them. Amchitka seemed to offer an option.

“So, some Alaska Department of Fish and Wildlife biologists said ‘hey, wait a minute. This is part of a national wildlife refuge and if you’re going to set off these atomic bombs, we want to mitigate that,’” explains Jameson.

The nuclear test would be the largest the United States had ever attempted; so perhaps it encouraged government biologists to launch the most ambitious wildlife project they could conceive: round up wild otters off the shore of Amchitka and “translocate” them to sites along their former range, as distant as the southern coast of Oregon.

This became an unexpected opportunity for Oregon. Biologists from the Oregon Game Commission [now Oregon Department of Fish and Wildlife] came to Alaska to participate in this historic effort.

On a bright July day in 1970, a transport plane landed at the Cape Blanco Coast Guard airstrip north of Port Orford, Oregon. A crowd of onlookers had gathered with curiosity and excitement. They watched as men carried wooden crates off the plane, delivering 29 wild sea otters.

The otters were put into a floating holding pen. The next day, the pen was towed by a fishing boat toward a rocky headland, Red Fish Rocks.

Film footage shows men with gaff poles and landing nets, trying to urge the otters out of the pen into the open ocean.

“Well, the otters were out of their minds by the time they were towed that far,” explains Jameson, “They had to practically force them to get out of the pens.”

Although sea otters are small, even tiny by marine mammal standards, they are the largest member of the mustelidae family — a group synonymous with “animals not to mess with” — which includes skunks, polecats, wolverines, and honey badgers.

When confronted, sea otters are feisty. They will hiss and bare their teeth — powerful enough to crack clamshells. Or swipe with their retractable claws.

“It wasn’t at all what we would call a ‘passive release,’” Jameson said. “But, they didn’t know. This was all groundbreaking stuff.”

Many of the otters had already swam back to Port Orford by the time the boat returned.

Sea Otters are often considered one of the cutest animals, but they are actually feisty by disposition and are the largest member of the animal family that includes skunks, wolverines, and honey badgers.

The sea otters at the Oregon Coast Aquarium are one of the most popular attractions. Considered "cute" by many, sea otters are actually feisty by nature. Related to honey badgers and wolverines, they are a wild animal best to be seen from a distance.

Ian McCluskey

Hope, then ghosting

The next year, 64 more otters were released off the Oregon Coast.

Jameson was just starting his graduate studies at Oregon State University. He was looking for a research project. At the right place and right time, he signed up to monitor Oregon’s new population of sea otters.

He spent countless hours on beaches and bluffs with his binoculars, tallying their numbers and jotting observations in his field book.

For the first couple years the few dozen otters hung on, in fact, they began to have babies, and the mood was optimistic.

“When I found those first pups I was really excited,” recalls Jameson. “I thought: ‘Man, this is going to happen!’”

But the next few years started to tip into decline.

Just two years after the releases, Jameson estimated that only one-third of the otters remained on the Oregon Coast. Two-thirds had mysteriously vanished.

By 1982, the population had disappeared completely.

For a second time, Oregon had lost its sea otters.

A sea otter mother and her baby swim in the icy waters of Alaska's Prince William Sound.

A sea otter mother swims on her back, holding her sleeping baby on her belly. The mother will hold her baby, leaving it only to dive for food. Baby sea otters can't swim, but their fur is so dense and fluffy, they float.

Ian McCluskey

Surviving to the north

No one knows exactly why the sea otters vanished from Oregon. There didn’t seem to be a lack of suitable habitat or food. And adding to the mystery—the small handful of sea otters released off the shores of Washington managed to hang on.

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In 1969 and ’70, 59 otters from Amchitka were transported to the tip of Washington’s Olympic Peninsula and released near the town of La Push. Not long afterwards, many were found washed ashore, dead. Researchers estimated that as few as 10 survived.

Yet, the population stabilized, then began to grow.

Since 1989, a formal population count has been performed by the U.S. Fish and Wildlife Service, Washington State Department of Wildlife, the Seattle Aquarium, Point Defiance Zoo and Aquarium, and Quinault Indian Nation.

By 2017, more than 2,000 otters were counted off Washington’s coast.

Jameson thinks perhaps the Alaska otters released in Oregon headed north, pointed by a homing sense. Perhaps they combined with the Washington otters, he wonders.

Unfortunately for researchers, none of the translocated otters had been marked. “We would have learned so much had they had some kind of marking, a flipper tag, an ear tag,” Jameson said. “If an otter was captured or came up dead on the beach in Washington State, we might have known ‘oh, this otter was released in Oregon.’ So, that would have told us a lot. Right now it’s all supposition.”

Two sea otters slowly swim on their backs. When not diving for food, sea otters will conserve their energy to stay warm in the icy water of the Pacific.

Two sea otters slowly swim on their backs. When not diving for food, sea otters will conserve their energy to stay warm in the icy water of the Pacific.

Ian McCluskey

Feast or die

Today, the only place to see sea otters on the Oregon Coast is at the Oregon Coast Aquarium in Newport.

“Our three sea otters are deemed ‘non-releasable’ by U.S. Fish and Wildlife, and they have a very comfortable life here at the aquarium,” said Brittany Blades, curator of marine mammals at the Oregon Coast Aquarium. “They eat better than I do!”

Every day, each of the three sea otters get a heap of fresh, restaurant-quality seafood—about 16 pounds each of Tillamook butter clams, shrimp, and Dungeness crab. An otter, weighing about 65 pounds, will eat more than will one of the 500-pound sea lions at the Aquarium. Sea otters can eat up to 25% of their body weight each day.

Each year it cost the aquarium $22,000 to feed just one of its otters.

“They don’t have that layer of blubber like other marine mammals do,” Blades said. “So one of their adaptations is a fast metabolism, meaning that they have to eat a lot of food.”

Their dense fur keeps the icy ocean water off of their skin, but to keep their body temperature up, they need to burn a lot of calories.

In the wild, sea otters dive for their food, often in the shallow waters of inlets, bays, and estuaries. They can feel with hands as sensitive as ours; remarkably, cold water doesn’t decrease their sensitivity.

They scoop up clams or other easy-to-catch creatures like urchins. They even have a flap of skin, like a pocket, to hold food so they can get more per trip.

They may grab a flat rock to use to smash open clams.

When not actively diving for food and eating, otters spend much of their time gently floating on their backs, resting, and conserving their precious calories.

In the wild, biologists have learned that otters have a fragile existence — they seem to be always on the verge of starvation.

Every morning the sea otters at the Oregon Coast Aquarium are coaxed onto a scale to track their health. With voracious appetites, it costs $22,000 a year to feed one of the otters.

Every morning the sea otters at the Oregon Coast Aquarium are coaxed onto a scale to track their health. With voracious appetites, it costs $22,000 a year to feed one of the otters.

Ian McCluskey

Second generation, second chance?

Similar to Jameson who was a master’s student at Oregon State University during Oregon’s first relocation, Dominique Kone was a graduate student at OSU looking for a research topic for his master’s thesis. The right person at the right time, it seemed, Kone found himself at a vanguard of a new interest in bringing sea otters back to Oregon.

“I’m trying to answer two questions,” he states. “The first one is very simply: does Oregon even have suitable sea otter habitat? Where is it? How much is there?”

Using geographic information systems, or GIS, mapping and computer modeling, Kone concluded that Oregon did have enough habitat to potentially support just over 4,500 otters. It is the first time a carrying capacity has been calculated.

He took his project a step further, looking at his maps to see where the places he’d identified as potential sea otter habitat overlapped with human uses.

Among the highest concerns about bringing sea otters back would be the potential impact on the harvesting of Dungeness crabs, Oregon’s most lucrative fishery. Over the past 20 years, an average of 17.3 million pounds of Dungeness crabs have been caught annually off of the Oregon Coast and in the mouth of the Columbia River, valued at an average of $39.5 million dollars each year, according to the Oregon Department of Fish and Wildlife.

Related: Oregon sea otter return encouraged by cost-benefit analysis

After analyzing his GIS maps and data, Kone’s research revealed hopeful results — the intersection of potential sea otter habitat and commercial crabbing areas was not high. This research supported what otter biologists like Jameson had observed in their field work.

“When I was doing studies, we found otters hanging out in rocky habitats, and the crabs they ate were mostly crabs that have no commercial value, red rock crabs, kelp crabs, things like that,” he said.

Commercial crab boats set their traps in deeper water than otters prefer.

“Diving down to 300 feet, for a sea otter, takes a lot of energy, and the cost-benefit ratio has to work out," Jameson said. "You can’t keep diving down for something to eat that you burn up more energy getting. You’re not going to last very long doing that.”

This wild sea otter in Prince William Sound, Alaska, is a descendant of the few otters that survived the Fur Trade.

A wild sea otter swims as he snacks on seaweed covered with roe. Sea Otters must consume as much as 25% of their body weight daily to survive in the chilly waters of Prince William Sound, Alaska.

Ian McCluskey

Urchins, otters, kelp

In the decades without sea otters, populations of urchins have significantly increased, and a small commercial fishery of urchin divers has developed. A return of sea otters would likely drastically reduce the number of urchins, according to Kone’s study. However, this may have a positive economic and ecological benefit.

In those areas where urchin populations have expanded, they have grazed down the kelp forests. Areas once thick with kelp are now bare.

“Without having sea otters as that keystone species in that ecosystem, you end up seeing the sea urchin population increasing,” Blades said. “They don’t have their top predator, the sea otter, and then they end up eating down that kelp forest which a lot of different marine animals depend on. Everything from small marine invertebrates like sea cucumbers all the way up to fish and even whales will depend on a healthy kelp forest.”

“So, it’s thought that if we bring sea otters back into the ecosystem, they can increase species diversity and improve the overall health of the ecosystem,” Kone said.

Kelp forests once grew thick here, but have been grazed down by growing populations of sea urchins.

Kelp forests once grew thick here, but have been grazed down by growing populations of sea urchins.

Oregon State University

Otters on the horizon?

Jameson scans the shore at Yaquina Head. It must have been 20 years ago, he figures, that he came here to confirm an otter sighting. A lone male, offering the flicker of possibility that otters from the north might drift south to Oregon.

In the years since, a few public sightings have been called in. They are always a lone male. These are exploratory missions of juvenile males to seek out new territory. But unless a female follows, the male will move on, and keep looking.

Biologists estimate that it may take at least 50 years, possibly a century, for otters to naturally move south on their own from Washington to Oregon. Or it may not happen at all. In places like Simpson Bay, Alaska, part of Prince William Sound, the wild sea otter population seems to have stabilized. In balance with the available food, the otters there have no incentive to look elsewhere.

As researchers learn that the chances are distant at best that otters will naturally repopulate Oregon, interest is growing in what it might take to attempt another reintroduction.

The Elakha Alliance, a nonprofit organization based in Siletz, Oregon, has been one of the primary advocates for returning sea otters to the state. Elakha is the word for sea otter in the Clatsop-Chinookan language.

This year, the alliance was awarded $40,000 from the U.S. Fish and Wildlife Service to conduct a feasibility study of sea otter reintroduction in Oregon.

Following the feasibility studies would come environmental impact studies, public hearings, a reintroduction plan, and sign off from multiple government agencies, said Bob Bailey, board president of the alliance.

“Right now we’re still very much in the information-gathering phase,” Kone said. “I think that we are still trying to figure out what the actual reintroduction process would be. I think one of the great things about what we’re doing now, is that we are ahead of the decisions before they’re actually made.”

For now, the reality is still years away.

“Oh I’d like to see them here,” Jameson says, gazing out at the ocean from Cobble Beach. “A little raft of them like I saw that one time…” He squints, as if picturing the sight of the small furry faces bobbing in the surf. “But you know, I’m afraid it’s not going to happen in my lifetime…” He pauses, then chuckles. “Unless we bring them back!”

Retired biologist Ron Jameson was witness to Oregon's reintroduction of sea otters in the 1970s. He counted the population until it disappeared completely. He hopes to someday see sea otters off Oregon's coast again.

Retired biologist Ron Jameson was witness to Oregon's reintroduction of sea otters in the 1970s. He counted the population until it disappeared completely. He hopes to someday see sea otters off Oregon's coast again.

Ian McCluskey

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November 02, 2020 at 08:04PM
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Will Oregon see sea otters again? - OPB News

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