Tasmanian beaches have been littered with an abundance of “mysterious jelly-like creatures” in recent weeks, leaving beachgoers scratching their heads.
The creatures have been spotted from Coningham to Opossum Bay and along the east coast near the Tasman Peninsula.
Associate Professor Kerrie Swadling from the Institute for Marine and Antarctic Studies (IMAS) has identified them as salps, a type of zooplankton.
She said they are common visitors to local beaches but don’t turn up every year.
“They don’t have stinging cells like jellyfish and they’re not dangerous,” she said.
“They are semi-transparent barrel-shaped animals made up mostly of seawater, with a brown spot (their guts) inside.”
Swadling said salps may look simple but have muscle bands encircling their bodies that contract to propel them through the water.
“The seawater pumped through their bodies is strained through mesh filters, capturing algae and particles in the seawater,” Swadling said.
“After salp blooms like we’re seeing now, the water is often very clear because the salps have filtered out and eaten all the algae, so it’s the perfect time for a dive or a snorkel.”
The salps species Salpa fusiformis is currently flourishing in Storm Bay, but blooms are usually short-lived and will only last for up to 22 days.
It can survive in temperatures from 14 to 22 degrees but peaks at around 16.5 degrees.
“Under favourable conditions, this species can number up to 400 per cubic metre of water,” Swadling said.
“We know that, locally, salps are eaten by Blue Warehou (also called snotty trevally) and some seabirds.”
“But because they leave behind no hard parts in the stomachs of predators, it’s difficult to know which animals eat them.”
