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Creative Crabs


Plastic is everywhere. According to the United Nations, enough plastic waste to fill 2,000 garbage trucks is dumped into waterways such as oceans, rivers, and lakes each day. There’s plastic litter at the bottom of the ocean and on top of Mount Everest.

Now plastic has been found in another unlikely place: on the backs of hermit crabs. According to a study published in February in the journal Science of the Total Environment, hermit crabs are using plastic litter as shells.


Zuzanna Jagiello is a biologist at the University of Warsaw, in Poland. She’s the study’s lead author. “For me, a hermit crab in a plastic shell could be an icon icon someone or something that has important meaning (noun) The bald eagle is an American icon. of our times,”

Jagiello told TIME for Kids. “They don’t have homes, so they use rubbish.” Jagiello studies the Anthropocene age. That’s the geologic geologic relating to the age of rock and its history (adjective) The geologic age of dinosaurs was the Mesozoic era. age we’re in now. Scientists define it as the period in which human activity has had a major impact on the environment. Hermit crabs using plastic waste as shells is one example of that impact.

New Homes

Hermit crabs are small, soft-bodied crabs that live near oceans. To protect themselves from predators, the crabs typically wear seashells that have been left behind by dead sea snails.


But according to February’s study, at least 386 hermit crabs have been documented wearing garbage. Of the world’s 16 species of hermit crabs that live on land, 10 have been seen wearing trash. Nearly nine out of every 10 of those crabs were wearing plastic waste, such as bottle caps. The others wore glass or metal, such as broken lightbulbs or soda cans.

Jagiello says that she and her team first learned about hermit crabs wearing garbage when they noticed photos of them posted online. They decided to learn more by conducting research (see “Internet Ecology”).

TEMPORARY HOUSING Hermit crabs wear seashells to protect their soft bodies from predators. Recently, they’ve been seen wearing human-made objects made of plastic, glass, and metal.


For their study, the researchers scanned the Internet for photos of hermit crabs wearing trash. They found photos from all over the world. Some had been taken by scientists. Some had been taken by nature photographers. Many had been taken by people who were just curious.

What Does it Mean?

Scientists aren’t sure why hermit crabs are choosing litter instead of snail shells. But they have theories.

Some sea snail populations are declining. Hermit crabs could be turning to litter because they can’t find enough seashells.


It’s also possible that crabs are opting for plastic because it’s light and easy to carry. Or they’re drawn to its flashy colors.

Scientists agree that plastic pollution harms wildlife and habitats in many ways. But it isn’t clear that the crabs are in any danger.

CLEANUP Volunteers work to clean up beach litter. Pollution in our waterways is harmful to wildlife.


“It’s really an amazing example of the beauty of adaptation, how some animals are coping with the Anthropocene age,” Jagiello says. “What are the long-term consequences of these adaptations? We don’t know.”

Internet Ecology


To study hermit crabs, researchers used iEcology, or Internet Ecology. It’s a way of doing research. It uses information on the Internet to spot patterns in the natural world. For this study, researchers looked at photos of hermit crabs that people had posted online.

iEcology isn’t perfect. The data can be biased. For example, people are more likely to take and post a photo of a hermit crab in a plastic shell than a snail shell, because it’s more surprising.