Mote Marine Laboratory

Firing Up the Fleet

By: Nadine Slimak

Mote is operating a new fleet of vehicles designed to find red tide and help cut the costs of ocean monitoring projects.

Called “autonomous underwater vehicles,” the long, taxi-colored devices look like torpedoes and are programmed for missions — albeit ones to seek, not destroy. The battery-powered vehicles operate on a buoyancy-control system that takes in and expels water to move the vehicles up and down in the water column, all the time looking for signs of red tide. Called Slocum Gliders, the devices are produced by Webb Research Corp., and are outfitted with Mote’s patented BreveBuster, which detects the presence of red tide by looking at the light-absorbing properties of particles in water samples. The vehicles also measure salinity, water temperature and, in some cases, dissolved oxygen.

The gliders will work in conjunction with the seven stationary BreveBusters already attached to buoys and channel markers in the Gulf of Mexico from Sarasota south to Charlotte Harbor. The idea is to use National Oceanic and Atmospheric Administration, NOAA, satellite images of the Gulf to determine likely locations of plankton blooms then compare those images with actual data collected by the moving and stationary BreveBusters to determine whether there’s a red tide bloom.

In all, Mote will have three BreveBuster-equipped gliders in rotation for coastal monitoring out to about 40 miles. Dr. Gary Kirkpatrick, manager of Mote’s Phytoplankton Ecology Program expects to have two operating at a time.

“It’s an issue of trading spatial resolution for temporal resolution,” Kirkpatrick said.

Stationary BreveBusters are great at monitoring one location over a long period of time, while the ’Busters on the gliders are better at measuring many locations over a short period of time. “It’s the best of both worlds,” he said. “The two technologies work together to make a complete picture.”

The BreveBusters are designed to transmit data to researchers in a control room via satellite at set times, so scientists know what’s happening on the water as it’s happening, whether the information is coming from a fixed point or from a glider. Gliders will be programmed in advance for a set course, but scientists in a control room can change the vehicles’ heading with just a few keystrokes. Two of the gliders were paid for by NOAA and will be used to help determine the accuracy of that agency’s harmful algal bloom forecast. The third glider was funded by the Florida Fish and Wildlife Research Institute and will be in rotation with the other two until needed to monitor a specific area, Kirkpatrick said.

For instance, in 2005, more than 100 bottlenose dolphins died in the Panhandle. The deaths were later found to be red-tide related, but those findings were available only after a group of researchers went out in boats and physically took repeated water samples. Had a BreveBuster-equipped glider been available, a crew of two could have deployed the instrument, which could have monitored the area around the clock for a set period of time, sending its readings back to the control room. Costs for manpower and boat time would have been much less. “Because the gliders communicate with satellites, they can be operated anywhere,” Kirkpatrick said. “I could be in the control room in Sarasota operating a glider in the Indian Ocean if I needed to.”

The control room

The data from the BreveBusters beamed back to Mote scientists in Sarasota comes in numerical form — like dots and dashes once transmitted over telegraph lines. Now, as then, someone has to decode that information. Enter computer whiz Robert Currier, data technology specialist, who has written a program that automatically decodes the information. Taking it one step farther, he’s also created a system that formats the information from the gliders for display with Google Earth, a satellite view of the Earth available to the public free through the Google search engine. The program gives scientists such as Kirkpatrick a three-dimensional look at what’s happening in the water. “It allows them to see things in the water that they couldn’t see before,” Currier said. “It makes it so much easier to visualize the data. It lets people like Gary concentrate on the science and not the interface support.”

Taken all together, the system helps support a larger integrated Florida Coastal Ocean Observing System. That system, now in its early planning stages, would combine elements like gliders and BreveBusters with data collected by numerous other agencies, technologies and instruments to give better information to ecosystem managers and those dependent upon the oceans.

“Florida has one of the longest coastlines in the nation,” said Dr. Kumar Mahadevan, Mote president. “We’re also one of the fastest growing states in the nation. Having integrated tools that help us look at and understand our oceans better is important for managing our coastal resources and our impact on them.”

Learn more about: Ecotoxicology

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