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Creative Crabs


Plastic is everywhere. About 2,000 garbage trucks’ worth of plastic waste is dumped into oceans, rivers, and lakes each day. That’s according to the United Nations. There’s plastic at the bottom of the ocean. There’s plastic at the top of Mount Everest.

Now plastic has been found in another unlikely place: on the backs of hermit crabs. They’re using it as shells. This was published in a study in February in the journal Science of the Total Environment.


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. It’s the period when human activity has made a big impact on the environment. Hermit crabs using plastic waste as shells is one example of this.

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Hermit crabs are small. They have soft bodies and live near oceans. For protection, they typically wear seashells. They find shells left behind by dead sea snails.


But according to February’s study, at least 386 hermit crabs have been documented wearing garbage. There are 16 species of hermit crabs that live on land. Ten species were 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 and her team saw photos online of hermit crabs wearing garbage. They decided to conduct 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.


The researchers scanned the Internet for photos of hermit crabs wearing trash. They found photos from all over the world. Some were from scientists. Some were from nature photographers. Many were from 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. It’s possible that hermit crabs can’t find enough seashells.


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

Scientists agree that plastic pollution harms wildlife and habitats. 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,” 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.