A crab mystery

August 23, 2024 11:47 PM

These crabs congregate on Australia's shores in a spectacular fashion but their story remains a mystery. Faced with an enduring ocean mystery and next to no money, researchers studying thousands of crabs on Australia's southern coast have turned to the public for help.
posted by chariot pulled by cassowaries (7 comments total)

Thousands of volunteers help with research
With thousands of pictures to check, researchers are reliant on citizen scientists.

The images are loaded onto a website for people to review, so far more than 7,000 people have taken part and Dr Camprasse says their input is "vital".

I can look at ocean pictures to find crabs, and be useful? Where do I sign up? Scistarter?
posted by eustatic at 2:17 AM on August 24

I can look at ocean pictures to find crabs, and be useful? Where do I sign up? Scistarter?

https://www.zooniverse.org/projects/spidercrabwatch/spider-crab-watch
posted by chariot pulled by cassowaries at 2:44 AM on August 24 [3 favorites]

”Sometimes, there's so many crabs you can't even see the sea floor, like it's all crabs, it's just amazing."

Carcinization has gone too far!
posted by GenjiandProust at 5:25 AM on August 24 [1 favorite]

I mean, I would theorize that they gather for, basically, fertilization purposes and the continuation of the species. It's just a crorgy.
posted by mephron at 7:10 AM on August 24 [1 favorite]

Victorian Fisheries Agency

I know it's not Victorian in that sense but the image this conjured up was of monacles, hoop skirts and those old-fashioned cast-iron diving suits with the hoses and that is now my preferred idea of how these people go about their business.
posted by AdamCSnider at 11:08 AM on August 24 [1 favorite]

Some scientists! How have they not even heard of a crab rave? That's like their whole thing, man!


Ok, more serious answer: I thought this was a solved thing and a number of different crab species do this. And it's because they are taking turns molting and finding safety in numbers.

I swear I just saw a documentary on specifically about the giant spider crab talking about this. They form a big pile, some of them get to molting and get protected by piles of crabs that haven't yet molted, the ones that molt then rejoin the pile once their shells harden enough, and the next ones molt, etc.
posted by loquacious at 12:47 PM on August 24 [1 favorite]

I know Elodie - glad to see her work featured! It’s not just why the crabs congregate - as the article says (although not explicitly enough), there’s not enough known about the Great Southern Reef in general, even though it’s massive and incredibly important . Studying the crabs helps build that body of knowledge.
posted by andraste at 3:56 PM on August 24