Even so, "we were extremely lucky—from the first net we put down right through to the last, we were getting thousands of salps," said Everett, of the Fisheries & Marine Environmental Research Facility at the University of South Wales in Australia.
Transparent except for their guts, salps are difficult to see—especially the species studied, the one- to ten-millimeter-long Thalia democratica.
Everett has swum in a salp swarm, and he described it as being like "swimming through a pool of jelly balls."
"Every time you take a stroke, you'd touch some little pieces of jelly. It's an odd sensation, given you can't really see the salps in the surf zone due to the waves and whitewater."
Read More | "Huge Swarm of Gelatinous Sea Creatures Imaged in 3-D" | Christine Dell'Amore | National Geographic