Small jellyfish are sometimes washed up on the sands of the bay of Mont-Saint-Michel by the receding tide. They are harmless, but it is best not to pick them up as some of the marine animals in the bay feed on them. In summer, leatherback turtles (Dermochelys coriacea) sometimes wash up in the bay in search of jellyfish, which they love eating. The world's largest sea turtle is on the brink of extinction due to the proliferation of plastic waste in the oceans. Indeed, turtles mistake plastic for jellyfish, swallow it, and die of gastric or intestinal obstruction.