Gadget may sniff out birth of Red Tide
A new sensor scans the water for the genetic mark of the toxic algae. Scientists hope the device leads to an early alert system.
By CURTIS KRUEGER
Published August 8, 2006
VENICE - In the battle against the toxic algae called Red Tide, scientists are turning to one of the same techniques that police use to catch killers: genetic evidence.
Call it a kind of CSI in the search for Red Tide.
That's why University of South Florida scientists sailed a kilometer off the coast of Venice on Monday to deploy a sensor that can search for Red Tide, which killed thousands of fish in the Tampa Bay area last year and created an annoying smell that soured local tourism.
The hope is that the new sensor can become "a first step toward an early warning system" for Red Tide, said David Fries, who leads the Eco-Systems Technology Group at USF's Center for Marine Technology. Fries, USF professor John Paul and other members of the ecosystems group developed the sensing device.
The device placed in the water by the scientists Monday is a 4-foot-long black cylinder that contains a sophisticated genetic sensor. It tests the water and conducts an underwater analysis of the microorganisms' genetic material, similar to the way crime labs try to match a person to a crime using genetic evidence. The sensor then transmits the data back to shore.
The scientists chose to place the genosensor near Venice because Red Tide already has been detected off Lee and Collier counties, and it may eventually extend north to Pinellas County. The researchers would like to see if their new sensor accurately tracks the movement of the algae bloom.
Matthew Smith, a biosystems scientist with USF, plans to stay in Venice until Thursday. With help from the South Venice Yacht Club, he plans to visit the buoy every eight hours to take his own water samples, which can then be tested and compared with the genosensor's results for accuracy.
The new genosensors probably need another couple of years' worth of development. But for researchers trying to learn more about Red Tide, these devices can be "a new vista, a new lens they can look through," Fries said.
Currently, Red Tide often is first discovered by fishermen who find dead fish floating on the surface or notice its pungent smell. That means the Red Tide is not only present, but pretty far along in developing.
Fries likes to imagine a time in the future when a large grid of his sensors would constantly test waterways for Red Tide, then sound an alarm when a bloom first begins.
"We want to be able to see where it starts," Fries said.
That would help the public by alerting fishermen and tourism officials that Red Tide may be coming to shore. It also would help scientists learn more about when, how and why the algae starts to bloom, which is not well-understood now.
And that, in turn, could become the ultimate weapon against Red Tide. Although it is understood that humans can aggravate algae blooms by polluting waterways, most scientists think more study is needed to understand the complexity of how and why Red Tide gets worse.
The new genetic sensor is not the only way to detect Red Tide. Biologists have been recording Red Tide events off Florida's west coast for decades, and researchers sail out to designated spots to check for it.
Mote Marine Laboratory in Sarasota developed a Red Tide sensor that uses optical technology, which has benefitted scientists there and elsewhere.
But Fries said USF's new genosensor is an advance because the genetic test is more accurate and zeroes in on a specific organism.