Leaping snails: the small, slimy acrobats of the forests of the Northwest

The Pacific Northwest is home to a group of rare species you’ve probably never heard of. Their name alone may scare or delight you: jumping slugs.

Environmentalists and the federal government clash over a species whose populations appear to be declining, along with its habitat in Washington’s Olympic Peninsula.

It is not a salmon or spotted owl or even a salamander.

It is a snail and it jumps as it were.

Unless you’re a malacologist, as mollusk experts are called, it’s unlikely you’ve seen or even heard of this five-inch-long creature: the Burrington Leaping Snail.

The inhabitant of fallen maple and alder leaves can only be found from Vancouver Island to the Oregon Coast Range.

While fans say the tiny mollusk has a certain charisma up close, it’s camouflaged and stealthy enough to avoid detection by accidental invaders in its mossy rainforest habitat.

Most slugs are known for gliding slowly and slimy on the ground, but at least a half-dozen species in Washington, Oregon, and Idaho are referred to as jumping snails for their habit of wriggling and flopping like a fish in water. Biologists believe it is a defense mechanism.

The snails can’t get any air, but they can fall off a branch or leaf they are sitting on and break free from their own slime trail to drive a hungry predator away from the scent.

“Yeah, they jump,” says biologist Michael Lucid of Selkirk Wildlife Science in Sandpoint, Idaho. “But they don’t jump like you might imagine.”

“Yes,” said retired Olympian biologist Bill Leonard, hesitantly. “More like somersault or something than jumping.”

Above, a leaping dromedary, a close relative of the Burrington, strikes Vancouver Island.

“It’s kind of like a corkscrew, coiling and unrolling tight that causes them to fall out or tumble,” Leonard said.

He saw his first slug jumping on the Olympic Peninsula in 1982.

“I was out there watching spotted owls and saw these crazy snails,” Leonard said.


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Like spotted owls, the leaping slugs are considered an indicator species for forests in the Northwest.

Jumping snails are sometimes called semi-snails: they sit halfway between snails and snails and carry a sort of half-shell around in a hump on their backs.

Nudibranchs are snails whose ancestors gave up all or most of their shells at some point in their evolution.

If you’ve ever thought about snails, chances are you think of them as slimy pests that can make gardening a frustrating exercise. Mollusc experts say the garden and crop destroyers are almost exclusively European species that have somehow taken a ride across the Atlantic.

There are at least six species of snails in the Pacific Northwest.

“These are integral inhabitants of our northwest forests,” Leonard said. “They are not found anywhere else in the world.”


caption: A Burrington leaping nudibranch, with its multicolored hump hiding partial shell, on Rialto Beach in Olympic National Park in 2001

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The Burrington Leaping Nudibranch glides through wet forests from the Oregon coast to Vancouver Island, where biologist Kristiina Ovaska studies a variety of tiny creatures. (“All things slimy and flaky,” she said.)

Other people go birdwatching. Ovaska goes to watch slugs.

“You have to look very closely, leaf by leaf, and you can find them on the forest floor,” she said.

The Burrington snail may never be a Northwest icon like salmon or killer whales, but Ovaska says that if you get close enough, it has a certain charisma.

It has a multicolored hump like a dazzling little backpack. His eyes are at the end of cute little eyelets.

“We have tail droppers and jumping slugs, and we have these really cool native species in our forest that most people know very little about,” Ovaska said.

Spring snails may not have many fans, but they do have avid fans.

In England, there is even an Ugly Animal Preservation Society that champions Northwest jumping snails, among other strange species.

“A slug, with a hump on his back, and he can jump, where’s his Disney movie?” asks a society video. “We have the Hunchback of Notre Dame. Where are the dromedary jumping slug and the princess?”

(In a competition to choose the Ugly Animal Preservation Society’s mascot, voters chose the blobfish over the dromedary jumping snail, a close relative of the Burrington.)

Conservationists plan to sue the federal government to keep the Burrington from becoming extinct.

In November, the Center for Biological Diversity gave the U.S. Fish and Wildlife Service the required 60-day notice of its intention to sue the agency for failing to provide endangered species protection to four species: the Burrington’s jumping snail, the Southern rubber boa -California, Florida’s Black Creek crayfish and a fish from Utah called the Virgin River spinedace.

The center also said it would sue the agency for delaying protection of another six species, including the Oregon and Washington Siuslaw tiger beetle.

The Fish and Wildlife Service found that the jumping slug had problems throughout much of its range, especially along Hood Canal, Willapa Bay and on Vancouver Island.

When their habitat is cleared, the snails cannot slide or jump fast enough to find a suitable wet and shady place to live.


caption: A jumping Burrington snail clings to a log on Vancouver Island.

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Burrington Jumping slug will continue to decline in levels of resilience, redundancy and representation within 20 to 50 years, the agency concluded.

Still, the agency said the species had “moderate” resilience and did not warrant new measures to protect its habitat, prompting the lawsuit.

“We need to better protect our forests and old-growth forests,” said Noah Greenwald of the Center for Biological Diversity, the group that is filing a lawsuit to protect the nudibranch as an endangered species.


caption: More molluscs, mostly land snails, are known to have gone extinct in modern times than any other type of animal.

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As far as scientists have been able to document, more mollusks have gone extinct in modern times than any other type of animal. The few people who study these overlooked animals feel they deserve more respect, especially given all the work they do for us.

“Decomposition isn’t as sexy as pollination,” Lucid said. “Yet it is a super essential ecosystem service.”

“Imagine a world without decomposers,” he said. “Imagine the leaf litter that would build up on the forest floor, and all the fuel that would feed these fires that are getting worse. So the species group is very important to humans.”

Nearly 20 years ago, the US Forest Service said the Burrington snail relies on old-growth forests. Lucid says it can thrive in younger forests too, as long as loggers leave microhabitats with shade and woody debris, the snails can stay cool underneath — and as long as our changing climate doesn’t dry out the wet patches the snail calls home.

“It’s definitely sensitive to warming temperatures,” Greenwald said.

“The ecosystems we all depend on that are made up of species are starting to unravel around the world,” he said. “The Burrington snail may seem like a small species, but it’s one of those that got caught up in it.”

Extinction and our unraveling climate are ongoing tragedies, but there is also comedy about jumping slugs.

While some experts say jumping slugs don’t actually jump, Tim Pearce, the curator of molluscs at the Carnegie Museum of Natural History in Pittsburgh, says they can jump higher than the Empire State Building.

That’s because the Empire State Building can’t jump.

“I once told my friend that I was going to the Olympics to see the jumping slugs,” Pearce said. “And she said, ‘I didn’t even know that was an Olympic event.'”


caption: A Burrington Leaping Nudibranch on Vancouver Island

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People who study these overlooked little creatures seem to develop a real fondness for them.

In Idaho, Michael Lucid and his wife, biologist Lacy Robinson, named a species of jumping snail they discovered in 2018 after their young daughter, Skade. They had named her after the Norse goddess of winter, mountains, skiing and archery. The Skade snail, research has found, lives in the coldest nooks and crannies of Idaho’s Coeur d’Alene Mountains and may be particularly sensitive to climate change.

“These are species that need it cold, they need it wet, and anyone who’s lived in the Northwest this past summer knows that’s changing,” Lucid said.

Ovaska said another rare mollusk, the blue-grey tail dropper, appeared to have disappeared from the spot she studies on Vancouver Island after this summer’s drought and extreme heat.

Now Lucid and Robinson hope to find another new mollusk species to name after Skade’s little brother.

“Fair is fair,” Lucid said. “One day we will be in trouble if we don’t find another one for him.”

Lucid says he wants to make sure there are still snails around when his kids grow up.

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