How Tampa Bay researchers are keeping tabs on Florida’s endangered sawfish

THE WATERS OFF RATTLESNAKE KEY One recent morning, Tonya Wiley waded through 2 feet of water, carefully scuffling her feet to avoid stingrays. She was looking for another kind of breed: the endangered smalltooth sawfish.

Where are you, children? Wiley, 51, screamed in the mangroves.

In recent weeks, Havenworth Coastal Conservation, a nonprofit focused on Wiley’s sawtooths, has found and tagged three juveniles.

These three pups and two others found in 2021 make up the only tagged sawfish discovered in Tampa Bay since Wiley brought his research here five years ago.

This excursion was Wiley’s first time back to Rattlesnake Key since recent tagging, and she came back empty handed. But Wiley said it’s fine. Sawfish sightings are so rare in Tampa Bay that three sightings in one year is a career milestone for her.

I felt greedy to get that third, he said.

Sawfish blend into the sandy bottom, where they are well hidden from predators such as sharks.
Sawfish blend into the sandy bottom, where they are well hidden from predators such as sharks. [ Tonya Wiley ]

Sawfish numbers have dropped so low that the state wildlife agency has a hotline for people who can report sightings. In Charlotte Harbor to the south, people report seeing sawfish to officials five or six times a week. But in the Bay, researchers are lucky to get so many calls in a year, Wiley said.

The last remaining stronghold for population exists between Charlotte Harbor and the Florida Keys. This is what researchers call the species’ core habitat; the sawfish has protection from Everglades National Park to thank for its conservation in South Florida.

Wiley said that although he has only tagged pups in Tampa Bay, most of the reported sightings are of large mature sawfish. This is because pups stick to their hatcheries, while larger sawfish tend to wander off.

Related: What is it like to catch an endangered Florida sawfish?

When he tracks one down, Wiley makes a small cut and fits a transmitter the size of an AA battery to the animal before stitching it back together. These tags last for four years and allow researchers to track the animals using receivers located along Florida’s waterways.

There are more than 100 receivers in Tampa Bay and another 100 in the Gulf of Mexico. Members of the Sawfish Research Group, which includes Havenworth, the National Oceanic and Atmospheric Administration, the Florida Fish and Wildlife Conservation Commission, and Florida State University, operate these receivers.

Between all of us, we have lower Tampa Bay completely covered, Wiley said.

Wiley has a research license to catch sawfish with a gillnet. The net, hung vertically and used to catch fish with the gills, was banned by the state of Florida in 1994.

He said gillnets and the fishermen who used them are partly responsible for putting sawfish on the endangered species list in 2003.

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The networks are how those people made a living, he said. Instead of cutting the net to get the sawfish out of the net, most of the time they will kill the sawfish.

Now, one of the biggest threats to small swimmers are shrimp trawlers, commercial boats that haul in large nets used to catch shrimp, said Adam Brame, who serves as sawfish recovery coordinator for National Oceanic. and Atmospheric Administration.

He said the agency is revising its estimates for species health and population expecting sawfish to recover faster than previously thought.

We’ve come a long way in the last 20, 25 years, he said. We are optimistic about the trajectory of this species.

But sawfish still have many hurdles to overcome before they repopulate Florida waters.

The species found in the Gulf of Mexico and the Atlantic Ocean today are smalltooth sawfish, but these waters were shared with largetooth sawfish, which have not been sighted in the United States since 1961.

The last remaining largetooth sawfish are found in Australia, Brazil and the Indo-Pacific region.

Sawfish perform an important function in estuary communities by preying on sick or injured fish, crustaceans and cephalopods. They are also an important food source for larger predators such as sharks.

The cultural importance of sawfish is another cause of conservation. Some native societies believe they are supernatural beings who bring good luck, according to the Florida Fish and Wildlife Conservation Commission.

Brame said ocean debris, climate change and habitat loss are still the biggest threats to the littletooth species.

Researchers are also finding sawfish tangled in bungee cords used to secure shade covers to boat houses.

During storm events, they tend to end up in the water, and they were seeing more and more images of sawfish with that string cutting its way up its rostrum and ending up around its face, Brame said.

Researchers found this smalltooth sawfish with a bungee cord wrapped around its gills.  Ocean debris is one of the biggest threats to endangered species.
Researchers found this smalltooth sawfish with a bungee cord wrapped around its gills. Ocean debris is one of the biggest threats to endangered species. [ Florida Fish and Wildlife Conservation Commission ]

The sawfish’s rostrum, its long snout with teeth resembling a handsaw, is what gave the animal its name.

It’s such a unique feature, but it’s also kind of an Achilles heel, Bram said. That thing can get snagged so easily on a multitude of objects.

Tampa Bay is an important nursery habitat for juvenile sawfish, and its cooler northern waters may become more important to the animals as oceans warm due to climate change, Brame said.

Wiley and his team found the three all-male, about 2-foot-long, month-old sawfish in about 6 inches of water near the mangrove shoreline of Rattlesnake Keys.

Juvenile sawfish thrive in these shallow coastal waters, close to where they hatched. And it’s likely that the sandy expanse where the researchers tagged this group of pups is actually their nursery, Wiley said.

Rattlesnake Key, which also serves as a nursery for rockfish, snook and other marine life, is expected to become a state park soon. During the 2022 legislative session, the state set its sights on the island, though the acquisition is still pending.

Charlie Hunsicker, director of natural resources for Manatee County, said the county has pledged $3 million to help the state purchase the land. The acquisition would reverse an 18-year project by the state’s Forever Florida land conservation program.

This location stands alone as a bright spot and the ecological balance needed if we are to continue to support our meaningful recreational fishery here, Hunsicker said.

Wiley has devoted more than two decades of his life to sawfish conservation and said it was special to have found the pups of Rattlesnake Key so close to his Palmetto home, just a 10-minute boat ride away.

The world said, Tonya, I owe you a sawfish, he said.

In 2000, Wiley was turned down for work studying blacktip reef sharks. A few months later, she was asked to move from her home state of Texas to Sarasota for new research on sawfish, an animal she knew nothing about.

Now, Wiley said now that he can’t imagine doing anything other than working the sawfish field. She’s added Rattlesnake Key to her list of picnic spots, making sure to carve out more time to look for more elusive critters.

I’ll be out here tagging sawfish until I physically can’t take it anymore, he said.

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