Tainted Water could spoil mullet run

On Aug. 10, a group of friends and anglers will gather in Wabasso to enjoy an annual fishing tradition. Armed with cast nets, they’ll go out onto the waters of the Indian River Lagoon and fish for the largest striped mullet.

Phillip Pederson said some in the group are commercial fishermen, while others are local with long connections to the water. The whole event is all in good fun, but this year, that fun may be tempered a bit by the quality of the water they will be cast netting into.

By August, the northern reaches of the Treasure Coast begin to show signs of more and more small schools of mullet gathering together. Some of the mullet are about as long as a man’s finger known as finger mullet and they will eventually amass numbers into the billions as they gather in nearshore estuaries and start to travel south along Florida’s peninsula.

Anglers like Pederson wonder, however, how good that run of mullet is going to be this year.

“It seems like many of our fishing patterns are at least a month late,” he said. “It could be all the runoff, and of course, in the northern lagoon, there isn’t any grass and mullet live in the seagrass.”

Pederson said this time of year, he can observe when the mullet are starting to get ready to move when he sees schools of the important bait fish sweeping around the ends of docks near his home.

“The second day of lobster mini-season, the water coming out of Sebastian Inlet looked like it was flowing out of a coffee pot,” he said.

Grant Gilmore, scientist with Estuarine, Coastal and Ocean Science in Vero Beach, said mullet are to marine estuaries as the buffalo are to the Great Plains.

“They are like cows, they are grazers. They graze on plants, algae, bacteria, fungi and microorganisms low in the food chain we never see,” Gilmore said.

Mullet are one of the chief fishes found in the waters of the Indian River Lagoon. They are also found along beaches, up into brackish and freshwater rivers and area canals, and offshore out into the Gulf Stream.

“Mullet have a high productivity rate, converting all that energy they gather from what they eat into protein that goes into all the organisms that eat them,” Gilmore said.

Nearly everything that lives in, and along, the Indian River Lagoon eats mullet.

They are a primary food source for birds of prey and water birds, bottlenose dolphins and scores of fish species.

“Mullet represent the highest biomass of any fish that spends time in the mangrove communities and near the shorelines of the Indian River Lagoon,” Gilmore said.

Typically, this time of year, silver mullet about a year old migrate to the south, where they winter in the warmer waters of Biscayne Bay, Florida Bay and the Everglades. By October or November, the striped mullet push offshore where they are believed to spawn.

Geoff Quatraro of White’s Tackle in Fort Pierce said it’s a bit early to predict whether this year’s mullet run will be what the predators in the estuary require or whether it will be a year where few mullet migrate through the area due to poor water quality.

“Weather patterns may have more to do with the success of the mullet run than the runoff,” Quatraro said. “We made need to feel a decent cold front in order to get the push started.”

Quatraro said in Fort Pierce, the thick of the run occurs in September and into early October. He remembers fishing in 2004 between Hurricanes Frances and Jeanne, both September storms, when the mullet run and the fishing was spectacular.

Farther south, anglers are keeping an eye on the detrimental effects of the discharges from the St. Lucie Canal into the St. Lucie River and southern Indian River Lagoon. At maximum discharges, some 4.5 billion gallons of water per day, there is a several knot current pushing all the way out into the Atlantic Ocean.

“I don’t know what’s going to happen, but most of us are afraid to touch the water,” said Capt. Ed Zyak of Local Color Guide Service in Jensen Beach.

That sentiment is reflected by Pederson.

“I really don’t know what it’s going to be like,” Pederson said of the mullet run.


DIET: Zooplankton, dead plant matter, and detritus.

DIGESTIVE SYSTEM: Mullet have thick-walled gizzard-like segments in their stomach along with a long gastrointestinal tract that enables them to feed on detritus.

KEY FISH: They are an ecologically important link in estuarine communities. They feed by sucking up the top layer of sediments, striped mullet remove detritus and microalgae. They also pick up some sediments which function to grind food in the gizzard-like portion of the stomach.

GRASS CLEANERS: Mullet graze on epiphytes and epifauna from seagrasses as well as ingest surface scum containing microalgae at the air-water interface.