Across U.S. lakes and rivers, people are spotting strange, jelly-like blobs underwater—prompting viral posts and wild claims about “alien egg pods.” These slimy, translucent masses have sparked both curiosity and fear, with some calling them body snatchers or sci-fi hatchlings. But wildlife officials say there’s no reason to panic.

According to the Oklahoma Department of Wildlife Conservation, these creatures are bryozoans—harmless, ancient invertebrates that have been around for over 470 million years. Starting as microscopic organisms called zooids, they clone themselves into large colonies that help clean the water and support aquatic life.

Though they may look like something from a horror film, bryozoans are actually a good sign—indicating healthy water. Their appearance can be unsettling: soft, blob-like clusters clinging to submerged logs or docks, sometimes as big as basketballs. Still, they’re natural and pose no danger to humans.

Found worldwide (except Antarctica), these organisms flourish in warm weather, dying off in winter but leaving behind egg-like statoblasts for spring. So if you see one this summer, don’t worry—it’s not an alien invasion, just one of nature’s weirder wonders doing its part to keep our waters clean.