If you live on the East Coast, you may notice some strange blobs on the beach. Small, gelatinous balls are washing up by the thousands this summer.

Often called jellyfish eggs, they actually aren't related to jellies at all. They're called salps, barrel-shaped creatures that pump water through their bodies and filter out the phytoplankton that is their food. And right now, they're washing up in large numbers.

National Geographic reports, "Changes in wind direction or water currents will push the barrel-shaped animals on to beaches, which happens with some regularity, says Paul Bologna, director of the marine biology and coastal sciences program at Montclair State University in New Jersey. That’s what happened in Ocean City, Maryland, on July 11 and 12, and it’s what’s happened up in Cape Cod, where Madin says he’s heard reports of salp strandings this summer."

The strandings are really nothing to worry about. Like all other species, salps experience booms and crashes based on food availibility. Salps feed on phytoplankton, so when there is an abundance of phytoplankton, there is an abundance of salps. When the food disappears, the populations die off, and wash up. In response to an uptick in strandings earlier in July, Assateague Park Ranger, and Science Communicator Kelly Taylor told WBOC, "What we think we're seeing right now is that the population has crashed, and there's nothing for them to eat because they ate it all. That's why they are washing up on the beach.They are essentially starving to death."

The Metropolitan Oceanic Institute and Aquarium writes, "One reason for the success of salps is how they respond to phytoplankton blooms. When there is plenty of food, salps can quickly bud off clones, which graze the phytoplankton and can grow at a rate which is probably faster than that of any other multicellular animal, quickly stripping the phytoplankton from the sea... During these blooms, beaches can become slimy with mats of salp bodies."

While oozy beaches are not exactly an appealing prospect, it is also nothing to worry about. Salps are harmless, so you need not worry about being stung should you touch one. Remember, they aren't related to jellyfish and have no stingers. It just makes the beaches more, um, interesting places to visit during the temporary uptick in strandings.

A population boom happened in 2012 as well in the waters off of California. KQED reported, "Over the course of decades, the Pacific Ocean alternates between "warm" and "cool" phases. During a warm phase from 1977-1998, salps declined in abundance; the trend reversed after 1998 with a shift to a cool phase. Yet none of the years since 1998 have shown salp numbers even close to the banner year of 2012."

A video about their population booms can be found on Plankton Chronicles.

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Jaymi Heimbuch ( @jaymiheimbuch ) focuses on wildlife conservation and animal news from her home base in San Francisco.