Researchers fail to discover where walruses in the Arctic are hiding, with negative consequences for the protection of the animals.

Everyone can help with walrus spotting on a new website.

This article is from Trouw.

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Is this a walrus or a rusty oil drum? Not necessarily a question that the average Dutch person expects to give him or her a headache. But that may be about to change, at least if it's up to the World Wildlife Fund. For a new research project, WWF is asking Dutch people to analyze thousands of satellite images. Just at home, behind the computer, looking for walruses, as part of the Walrus from Space project.

It is now unclear where the estimated 25,000 mammals are located in the vast Atlantic Arctic.

"The melting sea ice is making them increasingly narrow," explains WWF Arctic expert Gert Polet.

From now on, anyone can help map the animals, in some 600,000 photos, so that researchers can see how many walruses there are, in which areas they live and what threat climate change and shipping pose.

The most active seekers get a place in a 'walrus detective scoreboard'.

Online call from the Scottish scouting

The project has been promoted in the Netherlands since this week.

In the UK, promoters WWF and the British Antarctic Survey (BAS) launched it a few months ago.

For example, Samantha Robertson and her two sons, ages 7 and 8, came across an online call from Scottish scouting to spot walruses.

"Just when the boys tested positive for corona and we had to stay home for ten days," says Robertson.

To get through the quarantine, the family decided to go walrus hunting from their flat in Edinburgh.

On sometimes grainy satellite images, they try to recognize whether brown spots on a coast are indeed walruses, or stones.

"Sometimes we had to argue for a long time before reaching an agreement."

A nice quarantine hobby, but WWF man Polet emphasizes the importance for the animals.

"If we know where the walruses are, we can see if protective measures are needed there, such as when the increasing number of shipping routes threaten their habitat."

In addition, global warming is a growing problem.

“Walrus forage for food at the bottom of shallow seas and use the nearby sea ice to rest. Due to the melting ice, they can often rest only on distant shores, so they have to travel ever greater distances to get to their food. it's getting harder and harder for them to survive."

Look for the walruses.

Spoiler: top right, close to the shoreline, is a group on the beach.

Look for the walruses.

Spoiler: top right, close to the shoreline, is a group on the beach.

Photo: WWF

Spotting walruses takes practice

Recognizing herds of walruses is indeed not easy, as

Trouw

puts it to the test.

Despite a helpful training module - "walruses can vary in color from light brown to reddish brown" - many of the satellite images are dark or fuzzy, for example due to cloud cover.

And it takes practice to recognize in a dark spot whether it is a walrus or a water puddle.

This is one of the reasons why recognizing the brownish walrus groups - which from space resemble an ant colony most - is not yet done by machine-learning computer programs, according to Arctic expert Polet.

Training a walrus search algorithm is 'inevitably the next step', says Peter Fretwell (BAS), one of the people behind the project.

"But recognition by people is already going very well, and it has the important additional advantage that it creates a lot of involvement in society."

The goal is for about 500,000 users worldwide to spot walruses online, in order to make a selection of potential walrus areas, which experts can verify.

Polet explains that walruses have been hunted for a long time, which has reduced their numbers worldwide.

"The population is recovering in some areas, but very slowly in others."

Previously, walruses were mainly mapped from airplanes, but the hope is that this can be done more effectively with satellite images and a little help from citizens.

A herd of walruses on an ice raft on Spitsbergen, Norway.

A herd of walruses on an ice raft on Spitsbergen, Norway.

Photo: Richard Barrett, WWF

Donate computing power to your computer

This is not the first time that citizens are being called upon to contribute to major research projects from behind their computers.

Early in the pandemic, for example, you could donate computing power from your computer for Covid19 data research - a call to which many gamers with powerful PCs heeded.

In addition, many internet users unconsciously contribute to the training of image recognition software - for example when you have to click on which photos to see zebra crossings or taxis as a security question from Google.

But this is the first study on this scale that en masse appeals to citizens to map an animal population, says Polet, who hopes to start a similar project with polar bears in the future.

"I hope enough people want to participate now.

'Walruses are very social and endearing'

"Walrus aren't exactly cute looking animals, but they do capture the imagination. They are very social and touching: mothers really care for and pamper their young, and teach them to swim."

The WWF man hopes that the Dutch will feel increasingly involved with the animal, especially now that a young walrus visited Den Helder and Harlingen in the summer.

In any case, the Scottish Robertson continues to scan satellite images for walruses, not only with her children, but also, for example, during her homework breaks.

"I work at a bank, and I don't often feel like I'm contributing to the world."

With this research she does have that feeling, "even if it is just a little bit".

Walruses on Spitsbergen, Norway.

Walruses on Spitsbergen, Norway.

Photo: Tom Arnbom WWF-Sweden

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