Friday, June 18, 2010

Big sawfish landings help scientists

Former Charlotte High School classmates Justin Huxstep, 18, and Craig Nichols, 19, went fishing for shark along the beach at Boca Grande one night a week ago and, after a two-hour fight with what they thought was a 12-foot shark, wound up landing something far more exciting.

The fish they'd caught - and released unharmed - was a rare smalltooth sawfish, an endangered species that was once commonly found along the U.S. coast from North Carolina to Texas.

However, its numbers dwindled rapidly within the past 100 years to the point the fish is rarely found outside its federally designated critical habitat, the Charlotte Harbor estuary and the 10,000 Islands in Southwest Florida.

The fish looked like "a dinosaur," said Nichols of North Port.

It had a snout "like a chainsaw," added Huxstep of Port Charlotte.

"It was incredible," he said. "Even if it hadn't been a 12-footer that took a two-hour fight to bring in, it would have been amazing."

The catch got more exciting, the men said, after they learned about its ancient heritage and rarity.

The animal, which has a skeleton of cartilage, is from the same evolutionary family as skates and rays. The first sawfish emerged about 100 million years ago; the modern smalltooth dates back 56 million years.

The local men's catch was one of two landings of large sawfish off Charlotte Harbor last week. The other was a 12.5-foot sawfish caught off the southern tip of Sanibel Island last Thursday.

Both catches were reported to a team of Florida Fish and Wildlife Conservation Commission scientists that is working on a comprehensive study of the fish. The team was awarded $2.5 million in federal funds this month to continue their research for at least the next three years.

The FWC asks people who encounter sawfish to report the encounter to the field lab at 941-255-7403. The data will be logged into a National Sawfish Encounter Data Bank maintained by the University of Florida. The FWC researchers also use the information in real time to tell them where to look for sawfish to sample.

Friday, less than 24 hours after learning of the second big-sawfish catch, FWC lead scientist Gregg Poulakis used the anglers' information to target the vicinity off Sanibel. The team hunted for another big sawfish using a longline of baited hooks, said Poulakis, in a phone interview from his boat.

Once one was caught, the team planned to determine the fish's sex, clip off a tip of a fin for DNA testing, scan its belly with an ultrasound device, draw a blood sample and tag the fish with both an acoustic signaling device and a satellite tracking transponder.

The acoustic device will allow the fish to be tracked if it swims into the Caloosahatchee River. The FWC maintains several dozen acoustic receivers in the river, said Poulakis.

The satellite device will allow the fish to be tracked for several days if it travels offshore, he said.

The team makes several fishing trips per month based on angler reports.

"We're interested in seeing the big picture; why are they here?" said Poulakis.

People have encountered more than 1,000 smaller sawfish, those measuring less than 9 meters, and 99 bigger sawfish since 1999 within the Charlotte Harbor area. The vast majority of the smaller fish were sighted within the estuary while the vast majority of the larger fish were sighted at the southern tip of Sanibel Island or Boca Grande Pass.

That raises a question: Are the big sawfish coming to the estuary to dine on migrating crabs and shrimp? Or are they returning to the estuary to give birth to pups?

Dr. Philip Stevens, research administrator for the FWC's Charlotte Harbor Field Lab, pointed out people usually encounter the big ones near the estuary between February and June. The research team also learned that's when most smalltooth babies are born.

They figured that out after discovering that smalltooth babies are born with a sheath over their toothy rostrums. The sheath disappears within about two weeks. Researchers have only seen sawfish with sheaths between February and June.

However, the season for encountering big sawfish also coincides with tarpon season, and some believe the sawfish, like the tarpon, are attracted to area passes to feed on shrimp and crabs that flow out with the tide, according to Frank Hommema of Fishin' Frank's.

"Most fish grow up here and then leave, like redfish and tarpon," he said of the estuary.

Hommema said he supports the FWC team's research "150 percent." It will identify the needs of the sawfish, and conserving those resources would also help numerous other species, he said.

Huxstep and Nichols said they took up fishing for shark this summer as a fun way to spend their summer break from college. Huxstep is an Edison State College student who plans to pursue a law education at the University of Florida and Nichols is a Florida Gulf Coast University student.

However, when they went out fishing just after 9 p.m. June 3, they never expected to land a sawfish.

"I had no idea what it was," said Nichols. "I mean, the only time I saw a sawfish before was at Seaworld."

The men first put a catfish on a hook. Something "chewed it up a little bit," so they replaced it with a freshly caught whiting, said Huxstep.

After 10 minutes, the "clicker" on his reel starting ticking and line began paying out, he said. He said after about five seconds, he set the hook with a "whack" of the pole - and the fight was on.

"Every time I would gain 5 yards, it seemed the fish would take out 20," Huxstep said. "It almost spooled me."

Finally, the fish was dragged on to the beach. Nichols then saw a sword-like blade lined with sharp teeth.

"It's a sawfish!" he exclaimed.

The duo took a few pictures before pushing the fish back into the water and watching it swim away.

"Oh, hands down, without a doubt, it was the catch of a lifetime," said Nichols.


Sun Herald

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