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How Tampa Bay researchers are keeping an eye on endangered Florida sawfish

Only five have been found in the bay since tagging efforts began.
 
Tonya Wiley, director of Havenworth Coastal Conservation, looks for endangered smalltooth sawfish while trudging through 2 feet of water near Rattlesnake Key.
Tonya Wiley, director of Havenworth Coastal Conservation, looks for endangered smalltooth sawfish while trudging through 2 feet of water near Rattlesnake Key. [ JACK PRATOR | Times ]
Published June 26, 2023|Updated June 27, 2023

THE WATERS OFF RATTLESNAKE KEY — On a recent morning, Tonya Wiley waded through 2 feet of water, carefully shuffling her feet to avoid stingrays. She was looking for another type of ray: the endangered smalltooth sawfish.

“Where are you, babies?” Wiley, 51, called out among the mangroves.

Over the last few weeks, Wiley’s sawtooth-focused nonprofit, Havenworth Coastal Conservation, has found and tagged three juveniles.

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

This excursion was Wiley’s first trip back to Rattlesnake Key since the recent taggings, and she came back empty-handed. But Wiley said that’s OK. Sawfish sightings are so rare in Tampa Bay that three taggings in a year is a career milestone for her.

“I felt greedy getting that third one,” she said.

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

Sawfish numbers have dropped so low that the state wildlife agency has a hotline for people to 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 that many calls in a year, Wiley said.

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

Wiley said despite only having tagged pups in Tampa Bay, most sightings reported are of large, mature sawfish. This is because the pups stick to their nurseries, while larger sawfish tend to roam.

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

When she does track one down, Wiley makes a small cut and fits the animal with a transmitter about the size of a AA battery before stitching it up. These tags last four years and allow researchers to follow the animals using receivers stationed along Florida waterways.

There are more than 100 receivers in Tampa Bay and another 100 in the Gulf of Mexico. Members of the sawfish research team, 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 by their gills, was banned by the state of Florida in 1994.

She said gillnets and the fishermen who used them are partially to blame for sawfish ending up on the endangered species list in 2003.

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“The nets are how those people made their living,” she said. “Instead of cutting the net to get the sawfish out of the net, most times they’ll kill the sawfish.”

Now, one of the biggest threats to the smalltooth swimmers is shrimp trawlers, commercial boats dragging big nets used to catch shrimp, said Adam Brame, who acts as the sawfish recovery coordinator for the National Oceanic and Atmospheric Administration.

He said the agency is overhauling its estimates for the species’ health and population — they expect sawfish to recover faster than previously thought.

“We’ve made a lot of strides over the last 20, 25 years,” he said. “We’re optimistic about the trajectory of this species.”

But sawfish still have many hurdles to clear before repopulating Florida’s waters.

The species found in the Gulf of Mexico and Atlantic Ocean today are smalltooth sawfish, but these waters used to be shared with largetooth sawfish, which haven’t been spotted in the U.S. since 1961.

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

Sawfish provide an important function in estuary communities by preying on sick or injured schooling fish, crustaceans and cephalopods. They are also an important food source to larger predators like sharks.

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

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

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

“During storm events, these tend to end up in the water, and we’re seeing more and more images of sawfish with that cord that has worked its way down its rostrum and ends up around its face,” Brame said.

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

The sawfish rostrum, its long snout with teeth resembling a hand saw, is what gave the animal its name.

“It’s such a unique feature, but it’s also kind of its Achilles’ heel,” Bram said. “That thing can get tangled so easily in a multitude of of items.”

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

Wiley and her team found the three sawfish — all male, about 2 feet long and one month old — in about 6 inches of water near Rattlesnake Key’s mangrove shoreline.

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

Rattlesnake Key, which also serves as a nursery for redfish, snook and other marine life, is slated 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, Manatee County natural resources director, said the county has pledged $3 million to help the state purchase the land. The acquisition would check an 18-year-long project off the state’s Forever Florida land conservation program.

“This location stands alone as a bright spot and the ecological balance that’s necessary if we’re going to continue to sustain our recreationally significant fishery here,” Hunsicker said.

Wiley has dedicated more than two decades of her life to conserving sawfish, and she said it feels special to have found the Rattlesnake Key pups so close to her home in Palmetto — just a 10-minute boat trip.

“The world was saying, ‘Tonya, I owe you a sawfish,’” she said.

In 2000, Wiley was passed over for a job studying blacktip sharks. A few months later, she was asked to move from her home state of Texas to Sarasota for new research into sawfish, an animal she knew nothing about.

Now, Wiley said now she can’t imagine doing anything but sawfish field work. She has added Rattlesnake Key to her picnic spots list, making sure to carve out extra time to look for more of the elusive creatures.

“I’m going to be out here tagging sawfish until I physically can’t anymore,” she said.