Invasive blue catfish are a problem in the Chesapeake Bay and its tributaries, preying on native seafood like the blue crab. To help keep them in check, local schoolchildren are eating catfish for lunch.

Ryan Kellman/NPR PRESTON, Md. — It's lunchtime at Preston Elementary School, on Maryland's Eastern Shore. Kids file in, get dollops of food on their segmented trays, and maybe grab a chocolate milk. But one option on today's menu is special, served alongside grapes and broccoli.

"I got a catfish sandwich!" announces Ben Rochon, a second-grader. Between mouthfuls, he tells me how it is: "It's yummy." He's eating a catfish cake, also known by its nickname, the "catty patty." Some kids like it with ketchup or mayo. Fifth-grader Teagan Donovan goes minimal.

"I like it by itself with no toppings, because it's pretty good by itself," she says. In Teagan's case, "by itself" is literal: "I ignore the bun." Preston Elementary School on Maryland's Eastern Shore, catfish sandwiches are a highlight of a local food initiative.

Not everyone's into the fish cake — after all, this sunny Friday is also pizza day at Preston, and cheese slices are tough competition. But more kids have been trying catfish when it's served a couple of times a month. That's good news to Beth Brewster, who oversees food services for Caroline County Public Schools. "It tastes great. It's great for you," she says of the fish cake.

It has another benefit: It's made with blue catfish. Since spreading to the Chesapeake Bay in recent decades, the fish has become an apex predator. It can grow to more than 100 pounds; its voracious appetite is fueling worries that it's eating too many native species.

"It tastes so good because it eats everything we love — crabs and rockfish, and all kinds of things that we love to eat," Brewster says.

Beth Brewster led her chefs in developing a catfish cake known as the "catty patty." Brewster is the supervisor of food services for Caroline County Public Schools. State officials first asked Brewster to help tackle this problem about eight years ago.

"I was like, 'Beth, we have this invasive species. It tastes pretty good, is what we've been hearing. Can you do something about it?'" says Karen Fedor, administrator of the Farm and Food Programs at the Maryland Department of Agriculture.

Fedor describes Brewster as an "out-of-the-box thinker" who'd be up for the challenge of experimenting with recipes that appeal to kids — and also conform with federal dietary requirements. That's how Brewster's team landed on a crabcake-like dish made of blue catfish.

"It was kind of fun for my chefs to play with the recipe," she says, adding that because they have USDA approval, the cakes can be served anywhere in the U.S.

The pandemic initially slowed the effort down, Brewster says. But then she heard that Virginia was partnering with a California-based program called Bay2Tray to connect seafood with schools. Brewster got in touch with a simple message: "I have a fish for you." Now, other school districts in both Maryland and Virginia are serving blue catfish. In Preston, a rural community near the Choptank River, kids are excited to do their part by chowing down on the catty patty.

"It kind of tastes like crabs, but in a fish way," says fifth-grader Raelynn Truitt. "It's like, really really good." Fifth-grader Teagan Donovan, at left, doesn't go for ketchup, mustard or mayo on her catfish sandwich. Classmate Raelynn Truitt is also a fan: "It kind of tastes like crabs, but in a fish way," she says.

Invasive fish came from the Midwest To Brewster, the blue catfish presents a bad news-good news proposition. It's invasive — and its white, flaky meat is tasty, in part because it's not a bottom feeder. It was first brought to rivers in Virginia in the 1970s for recreational fishing.

"Blue catfish are a large freshwater catfish native to the Midwest," says Branson Williams, manager of the Invasive Fishes Program for the Maryland Department of Natural Resources.

The idea, he says, was that people would catch the fish in a few rivers feeding into the Chesapeake. But brackish water in the bay would keep them from spreading.

"They're a freshwater fish; they should stay in those freshwater portions of the river," Williams says. But, it turns out, "they can handle some salinity." Zach Swann sorts through the day's catch of blue catfish at a dock on the lower Potomac River. The species was first brought to rivers in Virginia in the 1970s for recreational fishing. It's spread to every tidal tributary of the Chesapeake Bay in Maryland.

You could even say those officials got catfished. Because in 2018, when Virginia and Maryland had record rainfall, the blue catfish used all that fresh water to leave those rivers and find new habitats.

"They now occur in every tidal tributary of Maryland. They occur in the Chesapeake Bay proper," Williams says.

In some spots, blue catfish make up about 70% of the fish biomass, or total weight, Williams says. Virginia officials have also been raising the alarm saying the fish is out of control and threatening the seafood industry that relies on traditional species such as flounder.

Blue catfish reproduce quickly and eat important forage fish like menhaden. They also gobble up young crabs and fish, adding to stress on those populations.

If the Chesapeake Bay has fewer blue crabs, it would be a huge economic and cultural blow to Maryland. So the state is turning to the only predator the blue catfish really has: people.

It joins other states trying to tap humans' role as apex predators to combat invasive species. They include Kentucky Illinois targeting the Asian carp, and Maine Washington state's battle against invasive green crabs.

Rocky Rice likes to average at least 1,200 pounds of blue catfish on each outing on the lower Potomac River. The invasive fish is now his primary target.

A Maryland waterman turns from crabs to catfish On a recent sunny morning on the lower Potomac River, Rocky Rice is bringing his catch back to the dock. He's a fourth-generation Maryland waterman. But instead of crabs, his boat is full of blue catfish. He tosses them into ice tubs, sorting them by size. I ask how many pounds he hauled in.

"Right at a thousand," he says, as he slings a fat catfish into a crowded tub. "It's usually about a hundred pounds to a tub." That's actually a little light. Rice wants to average about 1,200 to 1,500 pounds. He goes out three days a week, pulling catfish from hoop pots that trap them in their nets.

Rice, at right, and Swann, his first mate, sort blue catfish by size and weight. Rice says the fish doesn't bring the high prices of some other seafood, but it provides a steady income for his small operation. He started fishing for blue catfish 14 years ago to stay busy when he wasn't crabbing.

Now that's all flipped around. The market for blue catfish doesn't bring the high prices of other seafood, but Rice says the market and steady volume of his catch are strong enough to sustain his small operation.

"What I started off as just something to do to fill in, in between other seasons, actually has turned into my primary job now." And Rice can fish for blue catfish year-round. Because they're invasive, there is no season or size limit.

"You can catch as many of them as you want," says Maryland Department of Natural Resources' Williams. "And you don't have to throw the little ones back. Please keep them all." Before we leave the dock, I ask Rice if he eats blue catfish himself. "Oh yeah!" he answers. "They're good. It's a snow white, mild fillet."

The lack of a "fishy" flavor means blue catfish is good for fish tacos, Rice says. But he has his own preference: "You know, I'm from the country. So, if we can, we want to deep-fry everything, like nuggets and fried fillets." Students at Preston Elementary select their lunches, including a catfish cake sandwich. On a recent visit, the school also offered fillets.

From the bay to school trays By early afternoon, Rice's catch will be on its way to a processor. And that's where things hit a bit of a bottleneck. Catfish is the only U.S. fish that's required to have a USDA inspection.

The rule is meant to protect the U.S. market from cheap imports. But it takes money and time for a seafood processor to have a USDA inspector on site. As a result, only four processors in Maryland are able to handle processing blue catfish, according to Williams — even with grants and other help.

Still, the fish is making its way to grocery stores and restaurants around the country; in Maryland, it's also in schools and food banks. After all, it's an affordable protein that comes from a sustainable fish. That makes it a good fit for Bay2Tray, which focuses on developing new markets for bycatch and invasive fish.

"Just yesterday, I shipped a pallet of the blue catfish to a university in Texas," says Jenn Lovewell, chief nutrition officer for Real Good Fish, the company that runs Bay2Tray. Rice secures his boat before heading back to his fish house in Maryland.

Both Lovewell and Brewster, the school official, say millions of pounds of the fish need to be harvested, just to maintain the status quo. "It'll never be eradicated," says Brewster. So she urges people to seek out the fish in markets and restaurants.

Or as Lovewell puts it, "Eat the problem and save the bay." Newly harvested blue catfish are quickly put on ice, ready to be sent to a seafood processor.