Anywhere in the world, it is very common to spot a stranded jellyfish on a beach.

However, this summer on the beaches of the U.S. East Coast thousands of knuckle-size, gelatinous blobs cover the sand.

What are they?

These creatures are known as salps. Even though their appearance resembles the jellyfish, they are more closely related to humans!

A Salp is a barrel-shaped, planktonic marine invertebrate animal. It pumps water through its gelatinous body, enabling it to move and feed at the same time.

How are they ending up on the beaches?

‘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.

Are they dangerous?

No, unlike jellyfish, they are completely harmless!

A “weapon” against climate change

Salps’ reproduction involves asexual budding, where one salp creates a connected chain of clones – which can reach lengths of up to 15 metres!

Eventually the chain will be broken, and the individuals release mature into females containing only one egg. Males from a previous generation then fertilise these young females, producing an embryo.

The “mother” then develops male sex organs, so it can fertilise other eggs whilst the embryo grows inside it. These cloning methods require them to gorge themselves on algae blooms (rapid increase in the population of algae in a water system) so they can pump out the chains of clones.

All that eating produces large faecal pellets that ‘sink rapidly, as much as a thousand meters a day’ says Larry Madin, executive vice president and director of research at the Woods Hole Oceanographic Institution in Massachusetts.

The algae the salps are eating, takes in carbon dioxide (for photosynthesis) whilst it is still alive. Therefore the faecal pellets the salps produce contain a significant amount of carbon dioxide, so as they sink to the bottom of the ocean, it’s essentially removed from the carbon cycle.

Paul Bologna suggests it’s one way of trying to balance out how much CO2 is in the atmosphere.

Photo sourced from: news.nationalgeographic.com