NEWS RELEASE

Florida Fish and Wildlife Conservation Commission

April 20, 1999

CONTACT: Jon Fury (561) 791-4730

BIOLOGIST EMPLOYS TINY RADIO TRANSMITTERS TO TRACK TRAVELS OF EVERGLADES BASS

Tiny radio transmitters implanted in largemouth bass may answer questions about the impact of fluctuating water levels in the Everglades marsh.

Do bass swim out into the deeper canals before being trapped during long-term droughts? Or do many bass end up stranded and die in the muck? What water levels are optimal for bass survival?

Those are some of the questions asked by Jon Fury, a fisheries biologist who heads the Everglades Investigation Project for the Florida Fish and Wildlife Conservation Commission (FWC). He and his assistant, Tim Roettiger, are currently tracking six radio-tagged bass through the 210-mile-square Water Conservation Area 2A west of Ft. Lauderdale in Broward County. They plan on tagging four more bass before the study concludes.

Fury emphasized that this is field research designed to uncover information helpful to the better management of largemouth bass in the Everglades. "I hope our findings will help us better advise water managers on how artificially manipulated water levels impact the bass in the marsh," Fury said.

The biologists make bi-weekly trips to the area and use a portable radio receiver with antennae to locate the fish. Fury said he can pick-up the signal up to a half-mile away. The tracking study began in November and will continue for another six months.

In that time the water in the marsh has receded from three-feet in depth to as low as four-inches with isolated depressions slightly deeper. Fury said each tagged bass has reacted to the dropping water levels differently.

One bass headed towards even shallower water and finally became trapped in a three-foot deep pothole. Another went straight for the 20-foot deep canal and--so far--has stayed. A third tagged bass traveled from the marsh into the deep water canal and then--inexplicably--returned to the shallow water.

The distance traveled by each tagged bass has also varied. Some have traveled less than a mile. The record-holder is Bass Number 813 which swam seven miles from the interior marsh to a canal junction near the Sawgrass Fish Camp.

"I expected that as water levels dropped, we'd find the bass moving to deeper water if at all possible," Fury said. "We didn't find that. Most of them stayed in the same general area. When the situation became critical, they took refuge in depressions teeming with forage fish.

Continued tracking of the bass is growing more difficult as the water in the marsh recedes even further, and hampers air boat operation. Fury said the air boat rides are increasingly bumpier, and getting stuck in the dried-up marsh becomes more likely.

"If this continues, we might not be able to get within range of these tagged bass in another week or so," he said. "At the same time the bass themselves are captives of the few remaining holes and depressions. Whether they will survive until water levels rise again is just one more question the study hopes to answer."