Scientists Searching For Elusive Largetooth Sawfish

August 6, 2009

Release from: Neil Johnson
Tampa Tribune (Florida)

TAMPA - Scientists will spend the next three months looking for what may be a phantom with fins.

In July, the National Marine Fisheries Service agreed to review whether the largetooth sawfish should be listed as an endangered species, kicking off a three-month study of its numbers, range and habitat.

There's one major difficulty facing scientists: finding a largetooth sawfish in U.S. waters.

Though its cousin, the smalltooth sawfish, still can be found, the last largetooth was seen during World War II, said Shelley Norton, program manager with the Fisheries Service.

The largetooth is a gargantuan fish, growing to 20 feet long and straining the scale at up to 1,300 pounds. Sawfish use their saw to unearth crabs and clams from bottom sediment or to stun schooling fish.

At one time, the largetooth inhabited shallow coastal waters along the Gulf Coast but the last was seen in Florida in 1941 and in Texas in 1943, Norton said. It has been even longer since one was spotted off Louisiana.

The fish are still believed to be in waters from South America to Mexico and some may make it to waters off the Texas coast.

But the U.S. Gulf Coast was probably the northern limit of its historical range, said George Burgess, director of the Florida Museum of Natural History's Florida Program for Shark Research.

"I believe it was always an animal that came into our water as a migrant," he said. "It didn't necessarily stay."

There is probably good reason to believe they have been wiped out in United States waters, he said.

The largetooth is in serious trouble elsewhere in its range, with the mouth of the Amazon River about its only population center. The largetooth is gone from the west coast of Africa, Burgess said.

The fish's size, unique saw and habitat of shallow coastal areas all helped contribute to its decline.

It was caught for food and as a trophy, with the saw, which scientists call a rostrum, hacked off and displayed as a souvenir. Sawfish are still sought for their fins.

The saw easily tangled in fishing nets and led to the fish being killed as fishermen and shrimpers dispatched them.

The Fisheries Service study was prompted by a petition from WildEarth Guardians, an environmental organization.

A major part of the study will be determining the sawfish's range and estimating its population. The assessment could lead to the fish being classified as an endangered or threatened species, Norton said.

The Fisheries Service, a branch of the National Oceanic and Atmospheric Administration, hopes to have the study finished by November and must make a decision on classification by July.

Even if the study shows the largetooth has no permanent population in United States waters, listing it would send a message to other countries about trying to preserve the fish, Burgess said.

The smalltooth sawfish was placed on the endangered species list in 2003. As few as 5,000 may remain, mostly confined to Southwest Florida after once ranging the coastline from Texas to New York.

It's difficult to tell the two species apart – counting teeth is the best way. The smalltooth usually has 23 to 34 teeth along each side of the saw; the largetooth usually has 14 to 21.

Also, their dorsal fins are in different locations on the back.

As part of a recovery plan for the smalltooth, the University of Florida is seeking the public's help tracking the rare creature to learn more about its numbers, range and any other information that can be gleaned.

The information will be added to a database kept by UF and the natural history museum; Burgess is involved in the sawfish registry.

Researchers are looking for information about encounters with sawfish, from catching one to spotting one. Even old photos of sawfish are useful, as are newspaper and magazine articles, books and historical reports.

The information gathered so far is improving understanding of the animal's distribution, Burgess said.

Youngsters stay upstream in rivers feeding estuaries. Juveniles – about 6 feet long – head to coastal waters, and adults spread out into deeper water.

Protection as an endangered species may have halted the decline of the smalltooth, but getting the fish back to its normal distribution in Florida could take 100 years.

"We can't get too cocky," Burgess said. "It's going to be a long recovery."

SAWFISH SIGHTINGS

The University of Florida is seeking the public's help in tracking the rare smalltooth sawfish. What information should you report?

• Your name, phone number and e-mail address

• Date, time and location of the encounter

• Number, size and behavior of the sawfish

• Your activity at the time, such as fishing, boating or diving

• Information on any tags, scars or other distinguishing marks

For information about sawfish and the recovery program, go to www.flmnh.ufl.edu/fish/sharks/sawfish.