Eighty years ago, farmers were encouraged to plant an innocuous ornamental plant from Asia to serve as cheap ground cover and feed for livestock. Decades later, entire hillsides, power lines and forests have been devoured in kudzu’s jungle-thick, creeping conquest of the Southeast.
Despite these potent, twining reminders of the danger posed by invasive species, America is once more attempting to stem a seemingly unstoppable tide of alien invaders.
This time, however, it’s not a vine that’s eating the South; it’s a fish that’s swallowing America’s waterways.
“We have four species of carp from Asia in the United States. All four are invasive, and they all negatively affect our ecosystems,” said Dr. Bernie Kuhajda, Science Programs manager at the Tennessee Aquarium.
“Invasive species don’t add positively to the aquatic environment,” Dr. Kuhajda said. “They wreak havoc and cause our native species to decline and — in some severe instances — to completely disappear.”
Grass Carp, Bighead Carp, Black Carp and Silver Carp were brought to the United States to control algal growth and plankton blooms in ponds in Missouri and Arkansas. When these ponds were inundated by floodwaters in 1993, the carp escaped and made their way to the Mississippi River.
In the last quarter-century, the carps’ rapid rate of reproduction has resulted in an unassailable spread throughout the length of the river and into many of its tributaries, including the Cumberland River and Tennessee River.
Once carp enter these ecosystems, their sheer volume stresses native species, which often find themselves outcompeted for algae, plankton, snails and mussels consumed by the invaders. Additionally, boaters on infested waterways are all too familiar with the infamously skittish Silver Carp, which hurl themselves out of the water like 20-pound javelins when spooked by the rumble of an approaching motor.
Government agencies have taken steps to stem the tide by constructing bio-acoustic fish fences that stop the fish in their tracks. These massive devices installed on riverbeds use a combination of sound and light directed into a curtain of bubbles to deter sound-sensitive carp attempting to move through the system of locks and dams.
Tennessee and Kentucky have also introduced per-pound subsidies and free gill nets to encourage commercial fishermen and fish processing plants to remove millions of pounds of carp from infested rivers.
A growing movement is attempting to transform this invasive bounty into a marketable source of seafood. Even though carp are a staple in the diets of many other cultures, thinking of them as dinner plate-worthy has been a difficult transition for Westerners to make.
“Carp are an important aquaculture fish worldwide,” said Frank Fiss, Fisheries chief for the Tennessee Wildlife Resources Agency. “These carp, particularly those coming out of Barkley and Kentucky Reservoirs, are definitely safe to eat.
“They’re not eating stuff off the bottom of the river. They’re actually feeding on zooplankton in the middle of the water column, so there’s not a long food chain to compound problem chemicals.”
Chefs who have prepared dishes with Silver Carp describe its flesh as flaky, delicately flavored and easy to work with. Sometimes, they say, a single bite can be enough to change a long-held opinion.
“I was very surprised by how delicious Silver Fin — Silver Carp — was and how easy it was to work with,” said Chef Tamie Cook, owner of Atlanta-based Tamie Cook Culinary Productions. “Carp has gotten a bad rap, but this fish is very clean, very fresh, very neutrally flavored.
“It’s also invasive, so we need to cook as much of it as we can. Teaching people that they can eat invasive species really does make a difference.”
On Thursday, Sept. 19, the Aquarium will host Serve & Protect, its annual seated dinner and live cooking demonstration highlighting sustainably sourced seafood. Cook hosts the event and chooses other chefs to join her on stage as special guests. This year, the selectees — Chef Michael Gulotta of New Orleans’ MOPHO and Maypop and Chef Ricky Moore of Saltbox Seafood Joint in Durham, North Carolina — will be creating dishes using Silver Carp.
At a recent taste test of Silver Carp on the plaza in front of the Aquarium, Cook and Chattanooga-based chef Charlie Loomis — another Serve & Protect veteran — breaded and fried samples of carp paired with a sour cream-based tarter sauce.
The dozens of curious bystanders who tried carp weren’t the only ones surprised by its palatability.
“I’ve always been told that carp is not good to eat — that it’s bottom-of-the-barrel, as far as seafood goes — but it’s absolutely fantastic,” said Mr. Loomis, the executive chef and part owner of Chattanooga’s Feed Company Table & Tavern.
“I’ve seen videos of invasive carp jumping in Kentucky Lake, and it’s frightening to think of that happening here in Chattanooga,” he said. “I’m ready to start serving it in my restaurant and get the word out, for that reason alone, but it’s absolutely delicious, too.”
In an effort to educate the public about Asian carp, the Aquarium has prepared a trio of informational videos covering the potential danger — both ecological and economic — posed by these invasive fish, the methods being used to remove them from waterways and why carp should be on more seafood aficionados’ radars.
View the video series, A Battle Worth Carping About, at https://www.youtube.com/playlist?list=PLjkmEccUchZbEYwxDE1KrxGauykYlGm4_
More details about Serve & Protect are available at https://www.tnaqua.org/serve-and-protect.