The red lionfish (Pterois volitans)WIKIMEDIA, ALBERT KOKTwelve-year-old Lauren Arrington was just trying to do a cool science fair project by testing how far into Florida’s freshwaters invasive red lionfish (Pterois volitans) could infiltrate. But the sixth grader from Jupiter, Florida, ended up learning that the range of salinities at which the fish can live is wider than previously known. She essentially figured out that the fish could live in nearly fresh water, which researchers didn’t expect. “Scientists were doing plenty of tests on them, but they just always assumed they were in the ocean,” Arrington, now 13, told NPR on Sunday (July 20). “So I was like, ‘Well, hey guys, what about the river?’”
The red lionfish, which Arrington studied, and a morphologically indistinguishable species, the common lionfish (P. miles), are endemic to the Indo-Pacific, but both are invading the Caribbean and Atlantic Ocean up the US East Coast. Divers, snorkelers, and anglers report increasing encounters with the fish in ocean waters, which are usually about 35 parts per thousand (ppt) NaCL, off the coast of Florida, among other places. Previously, lionfish were known to live in salinities as low as 20 ppt. But by holding fish in tanks and gradually decreasing the salinity of their water from 35 ppt downward, Arrington determined that the fish could survive salinities as low as 6 ppt.
When North Carolina State University ecologist Craig Layman heard of Arrington’s findings, he replicated her ...
