SHELL SHOCK
Marine creatures are making use of human pollution in creative ways. Two-thirds of hermit crab species have been found using debris that humans have discarded as ‘artificial shells’, instead of those left behind by molluscs.
In a study of hermit crab residences using photos taken by tourists and posted on social media and photo-sharing websites, Marta Szulkin, an urban ecologist from the University of Warsaw, explained, “We started to notice something completely out of the ordinary… Instead of being adorned with a beautiful snail shell, which is what we’re used to seeing – they would have a red plastic bottle cap on their back or piece of light bulb.”
Szulkin’s study found a total of 386 individuals using human junk as shells – mainly plastic caps. “According to our calculations, 10 out of the 16 species of land hermit crabs in the world use this type of shelter and it’s been observed in all tropical regions of the Earth,” she said. It is not clear whether using human debris as shellsdecline, it is possible that it might be becoming easier for the animals to find an artificial alternative, and the lighter, plastic ‘shells’ might even help smaller, weaker crabs to survive because they are easier to carry.
