Scientist hopes to change perception of common sea squirts –

Scientist hopes to change perception of common sea squirts Published:  09 March, 2006

SEA squirts are ubiquitous in marine environments and well known as nuisance globs that grow on ropes, pilings, and everything else humans put in saltwater. But Harbour Branch scientists, working in collaboration with Florida Atlantic University (FAU), are hoping that people may instead think of sea squirts as water saviours.

They say these filter feeders may help reduce the impacts of such Indian River Lagoon plagues as the neon-green alga that overcame parts of the estuary last year in conjunction with high discharges of nutrient-rich waters from Lake Okeechobee. At the latest 2006 Ocean Science Lecture Series, Harbor Branch aquaculture expert Dr. John Scarpa yesterday for the first time publicly discussed work to explore the bioremediation potential of sea squirts.

“It may be a pie-in-the-sky idea,” said Scarpa, “but that’s what research is for and in our preliminary work we’ve definitely shown that the potential is there.”

Sea squirts naturally filter water, indiscriminately removing as food a wide range of particles present. Theoretically, that means the organisms could, if placed in an area in large enough quantities, remove species responsible for harmful algal blooms, or troublesome bacterial species that might be contaminating a waterway. To avoid unwanted proliferation of the species, the idea would be to place the sea squirts in a waterway in a contained fashion that would allow them to be moved to another area once filtering goals had been accomplished. The sea squirts would likely have to be one component in an overall plan to clean up water in a particular area.

Lisa Draughon, an FAU graduate student, began preliminary work with Scarpa last summer to explore the sea squirt bioremediation concept. She found that sea squirts native to the Indian River Lagoon do in fact filter substantial volumes of water – 100 of the small organisms can filter about 2,000 gallons of water per day – and that their filtering process will remove the common bacteria E. coli. Draughon will be pursuing the sea squirt research as her doctoral dissertation and she, Dr. James Hartmann of FAU, and Scarpa, are currently seeking funding to pursue sea squirt research targeted at the Indian River Lagoon.

Besides the bioremediation project, Scarpa also discussed benefits sea squirts already offer, namely producing chemical compounds that have shown promise as cancer treatments. One of these compounds was discovered by a Spanish company called PharmaMar and is currently in human clinical trials.

Dr. John Scarpa is an Associate Scientist in the Division of Aquaculture. His research concentrates on improving culture methods for aquatic organisms through breeding, nutrition, and environmental manipulation. is published by Special Publications. Special Publications also publish FISHupdate magazine, Fish Farmer, the Fish Industry Yearbook, the Scottish Seafood Processors Federation Diary, the Fish Farmer Handbook and a range of wallplanners.