ANNA MARIA – Clams are not the solution to red tide pollution, retired marine biologist Dr. Randy Edwards told city commissioners who are considering a proposed clam restoration project in and around Anna Maria.
Having heard from Edwards during the Feb. 10 city commission meeting, the Anna Maria Commission has not yet made a final decision regarding a $50,000 funding request for clam and seagrass restoration projects recently proposed by local restaurateur Ed Chiles and representatives of The Gulf Shellfish Institute, The Diatom Initiative and Sea & Shoreline.
Led by Chiles, that group seeks $50,000 of the approximately $850,000 in American Rescue Plan (ARP) funds the city has and will receive from the federal government over a two-year period.
Edwards’ appearance at the Feb. 10 meeting served as a follow-up to the letter he previously sent Commissioner Jon Crane. In that letter, Edwards addressed Crane’s concerns regarding the degree to which clams remove red tide cells (Karenia brevis) from the waters in which they live. The toxic algae can cause respiratory irritation, shellfish poisoning and fish kills during its bloom phase.
After hearing Edwards’ scientific positions and personal views on clams’ impact on red tide mitigation, Commissioner Robert Kingan suggested, and the commission supported, directing city engineers to research potential stormwater mitigation/nitrate reduction runoff improvements as possible alternative uses of the $55,000 in ARP funds included in the city’s current fiscal year budget for water quality/environmental projects.
Edwards’ views
Edwards, a Bradenton resident, told the commission he has nearly 50 years of experience in marine biology and ecology. He said he holds a master’s degree in marine science and earned a Ph.D. based on his study of nutrient dynamics in Florida’s estuaries.
Edwards said he served as a research scientist at the University of Miami, where he directed a large aquaculture/fish species project that included a saltwater fish stocking program. He said he was then hired by Sarasota-based Mote Marine Laboratory to lead Mote’s fish stocking program.
He said he later focused his efforts on research pertaining to the ecology of fish and fish habitats in Florida’s bays and estuaries and directed studies for the Sarasota Bay Estuary Program, multiple Florida water management districts, the Florida Fish and Wildlife Conservation Commission, the National Marine Fisheries Service and the U.S. Geological Survey.
“I have no dog in the fight. I’m free to speak the truth because I have no strings attached,” he said when noting he has no financial stake in the proposed restoration projects.
“I do believe that locally environmentally concerned citizens that have been involved in promoting clams as a way to mitigate red tide and nitrogen pollution actually do so out of very good intentions. The same applies to local organizations such as START (Solutions To Avoid Red Tide) and Sarasota Bay Watch. Almost all really believe that they are doing something very good for the environment. However, the scientific realities are that they have somehow become misinformed, or at least under-informed, and there seems to be some involved partially because of self-interest,” Edwards said.
“But clams are not the solution to pollution. The scientific fact is that even large populations of clams will not remove significant amounts of nitrogen. In some specific situations, clams could increase nitrogen and have negative impacts,” Edwards said, noting that clam waste contains ammonia that other organisms can convert into nitrogen.
“The main problem that we have facing our waters is the increasing nitrogen pollution in our bays, estuaries and coastal waters – nitrogen loading that continues to increase because of man-made increases mainly due to population growth and inadequate pollution control. That nitrogen increase causes severe ecological changes to our bays and estuaries, including increased phytoplankton blooms that shade out seagrasses and reduce water quality. The nitrogen also stimulates the growth of microalgae and seaweeds. That nitrogen increase surely contributes to red tides becoming more frequent and more severe,” Edwards said.
“I can say this with scientific confidence: There has been no scientific validation or evidence that stocking clams can or may significantly impact ride tide. There’s no science behind it. There is no evidence yet that clams have or will provide substantial mitigation. They won’t reduce red tide, they won’t reduce nitrogen,” Edwards said, when calling into question whether the proposed restoration projects are an appropriate use of the federal funds.
Edwards also addressed the assertion that a single clam can filter 4.5 gallons of water per day. He estimated there are approximately 100 billion gallons of water in Sarasota Bay, Anna Maria Sound and the local areas of Tampa Bay. For mathematic simplicity, he postulated that if a single clam could filter and clean 10 gallons of water per day, 10 billion clams would be needed for adequate filtration purposes in those local waters.
He cautioned that placing a large number of clams in Bimini Bay and its surrounding canals could act as a trap for the organic matter clams produce as waste products.
“I don’t think people really want that,” Edwards said.
In reference to Edwards’ comments, Commissioner Kingan said later in the meeting, “Having heard Dr. Edwards today, and knowing the other proposal that we had, it seems to me pertinent to consider talking to our own city engineers and seeing what they might propose for environmental mitigation and runoff treatment. We could ask the mayor to engage with them and see if they have a proposal that would be efficient, effective and something we could do to use this money we have.”
The commission reached consensus in support of Kingan’s suggestion.
Gulf Shellfish Institute Executive Director Stephen Hesterberg attended Thursday’s meeting but did not address the commission. Chiles did not attend the meeting. The group’s funding request was not included on the meeting agenda so no action was taken.
Related coverage
Decision still pending on clam, seagrass restoration funds
