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Alarming Amounts of Pharmaceuticals Found in Florida Redfish

Plus habitat diversification, Women Are Fly, and the March Merkin in the Fly Fisherman News Briefs for April 7, 2023.

A study conducted by Florida International University's (FIU) Coastal Fisheries Research Lab, funded by the Bonefish & Tarpon Trust (BTT), found that redfish sampled from nine estuaries throughout Florida are contaminated with pharmaceuticals. The study detected 17 unique pharmaceuticals in the redfish, with cardiovascular medications, opioid pain relievers, and psychoactive medications being the most commonly detected.

“The results underscore the urgent need to modernize Florida’s wastewater treatment systems,” said BTT President and CEO Jim McDuffie in a press release. “Human-based contaminants like these pose a significant threat to Florida’s recreational fishery, which has an annual economic impact of $13.9 billion and directly supports more than 120,000 jobs.”

Scientists and volunteer guides and anglers sampled redfish in nine of Florida’s most important estuaries: Pensacola, Apalachicola, Cedar Key, Tampa Bay, Charlotte Harbor, Florida Bay, Northern Indian River Lagoon, St. Augustine, and Jacksonville.

A map of sampling locations around Florida.
Scientists and volunteer guides and anglers sampled redfish in nine of Florida’s most important estuaries across the state. (Photo courtesy of Bonefish & Tarpon Trust)

A study from 2022 found similar results in south Florida’s bonefish, crabs, shrimp, and other flats prey-fish species.

“These studies of bonefish and redfish are the first to document the concerning presence of pharmaceuticals in species that are important to Florida's recreational fisheries,” said Dr. Jennifer Rehage, FIU professor and the study’s lead researcher. "Given the impacts of many of these pharmaceuticals on other fish species and the types of pharmaceuticals found, we are concerned about the role pharmaceuticals play in the health of our fisheries. We will continue this work to get more answers to these concerning questions.”

Although the study raises concerns, there is hope as research from Europe shows that most pharmaceuticals can be removed from the wastewater treatment process by applying ozone treatment to wastewater. Therefore, significant investment in Florida's water infrastructure is required to address pharmaceuticals and other contaminants of emerging concern.

Some specific findings:

  • Researchers sampled 113 Florida redfish for 94 commonly prescribed pharmaceuticals.
  • Redfish blood plasma samples were collected at nine Florida estuaries: Pensacola, Apalachicola, Cedar Key, Tampa Bay, Charlotte Harbor, Florida Bay, Indian River Lagoon, St. Augustine, and Jacksonville.
  • On average, researchers detected 2.1 pharmaceuticals per redfish; only seven redfish had zero pharmaceuticals.
  • Across all samples, a total of 17 unique pharmaceuticals were detected, comprising eight pharmaceutical classes.
  • Across estuaries, the number of pharmaceutical detections was highest in Apalachicola and Tampa Bay, intermediate in Charlotte Harbor, Cedar Key, Pensacola, St Augustine, and Jacksonville, and lowest in Florida Bay and Indian River Lagoon. The averages are as follows: Apalachicola = 3.3, Tampa Bay = 3.0, St. Augustine = 2.5, Cedar Key = 2.2, Jacksonville = 2.1, Charlotte Harbor = 1.8, Pensacola = 1.8, Florida Bay = 0.9, Indian River Lagoon = 0.9.
  • A total of 12 pharmaceuticals accounted for over 97% of detections. Harmful effects on fish have been documented for 7 of these 12 pharmaceuticals. These include, tramadol, caffeine, donezepil, dicolfenac, diphenhydramine, sertraline, and ranitidine while the effects of the remaining 5 pharmaceuticals (felodipine, flecainide, flutamide, flupentixol, and clotrimazole) remain unassessed.
  • The antiarrhythmic agent flecainide led detections, with 60 detections (53.1% of all redfish), while the synthetic opioid analgesic tramadol had 59 detections (52% of all redfish. Three other pharmaceuticals were commonly detected: caffeine (43.3% of samples), the psychoactive flupentixol (21.2% of samples), and the psychoactive donepezil (9.7% of samples).
  • Exposure to pharmaceuticals by redfish may occur by inhalation (via water/sediment) or through prey.
A researcher in a boat testing a redfish for pharmaceuticals.
A recent study detected 17 unique pharmaceuticals in the redfish. (Photo courtesy Bonefish & Tarpon Trust)

Montana Professor Advocates for Diversification of Trout Habitat

During a talk in Bozeman, Montana, Timothy Cline, an assistant professor of cold-water fish ecology and management at Montana State University, urged people that we need to adapt to the climate-change-induced loss of native trout habitats. The best way in his opinion is by maintaining and restoring “a diverse portfolio of habitats”, similar to diversifying assets in a retirement portfolio.

Cline and other scientists published a study that found anglers adapt by fishing in areas with colder waters during droughts, which means that the fishing economy remains strong. The study, entitled, “Socioeconomic Resilience to Climatic Extremes in a Freshwater Fishery,” projects that Montana could lose about 35 percent of its cold water by the year 2080.


To stay ahead of this, Cline and others are working on a cutting-edge drought-warning system that aims to help fisheries managers stay ahead of and cope with the changing climate.

Read more here.

Women Are Fly Event

Women are Fly Event 2023 poster

The 2023 Women are Fly event will be held on May 5-6, 2023 at the River's Edge Fly Shop in Bozeman, Montana. The event is designed to inspire and empower women to pursue fly fishing as a hobby or as a career.

Recommended


The event will feature a variety of activities, including fly casting instruction, fly tying demonstrations, and fishing clinics. There will also be opportunities to meet and learn from professional fly fisherwomen.

The event is open to women of all ages and experience levels. Registration is $50 and includes all activities and instruction.

Click here for more information.

Vallilee Wins March Merkin Permit Tournament

Kathryn "Kat" Vallilee has become the first woman to win the March Merkin tournament, the largest catch-and-release permit tournament in the world. Vallilee, who has fished in the last six March Merkin tournaments and finished second last year, was named Grand Champion Angler after landing the only permit in the entire tournament. The tournament, which took place from March 13-16, featured 25 teams of elite permit anglers. Vallilee's guide, Capt. Doug Kilpatrick, was named Guide to the Grand Champion.

Kathryn Vallilee and her guide Doug Kilpatrick holding permit art.
Vallilee won 2023's March Merkin tournament, catching the lone permit of the contest. (Photo courtesy of Hardy Fishing)

“I’ve been working hard to become more competitive in the field and fishing these tournaments has been a humbling experience,” Vallilee said in a Hardy Fishing press release. “The other teams in years past really showed me that I had a lot of work to do if I wanted to have a real chance at winning. Last year was a real heartbreaker for me, so for Doug and I to come back this year and win with such tough conditions felt really great.”

Vallilee fished a Hardy Zane Pro rod in her win.

The March Merkin has been put on by the Lower Keys Guide Association since 2006 as a benefit for the Lower Keys Guide Association and the Bonefish & Tarpon Trust. Full results are available here.

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