Chef Johnny Graham of the Home Port in Menemsha was one of the top 20 contestants on Bravo’s Top Chef. Chef Kyle Garell of Sidecar in Oak Bluffs started his own cooking show on Martha’s Vineyard Television. And while Mario Batali and Bobby Flay may not be there, Mr. Graham and Mr. Garell will go to head-to-head tomorrow as the West Tisbury Farmers’ Market becomes the next kitchen stadium.

Mr. Graham and Mr. Garell are throwing it down seafood-style in a cooking battle of local seafood and produce, all for the sake of promoting local fisheries on the Vineyard. Just as in traditional Iron Chef competitions, the chefs will be given a secret ingredient (some type of local fish) and then will be given 15 minutes and $50 to shop the farmers’ market. One hour later, judges Tina Miller, author of Vineyard Harvest, Katherine Long of Up-Island Eggs and Eleni Collins from the Martha’s Vineyard Times will decide who the winner is.

Not to worry — marketgoers will have the chance to taste the food as well.

The Northwestern Atlantic Marine Alliance (NAMA) is hosting the seafood throwdown, and for the past two years has held competitions across the Northeast, even one at the Union Square farmers’ market in New York city that was sponsored by the Food Network.

“It’s proven to be a great way for us to talk about the challenges in the fishing community,” seafood throwdown creator Niaz Dorry of NAMA said earlier this week. “Especially in a place that’s isolated like Martha’s Vineyard, how do you deal with the future and make sure the community has a way to fish for years to come?”

Ms. Dorry said educating consumers about local fishing issues is easier to do through something that has grown into more habitual practices — buying local produce. “It’s an interactive way for us to talk about issues people just don’t know about,” she said. “To do it in a way like the throwdown, as opposed to lecturing, opens up the opportunity for people to absorb info better. It’s a much more relaxed way than being told what to do.”

Warren Doty, president of the Martha’s Vineyard/Dukes County Fishermen’s Association, which is sponsoring the event, will be the competition’s master of ceremonies. “We’re sponsoring the event to highlight local seafood and what local seafood is available and how we’d like to see it in restaurants and people’s homes,” he said. “Our local seafood stocks are rebuilding and there is a great future for wild caught harvest on Martha’s Vineyard.”

Both Mr. Doty and Ms. Dorry thought the farmers’ market was the perfect place for this to happen, to pique people’s consciousness that local fishermen and farmers face similar issues.

“One of the things we want people to walk away with is, we have to see fisheries through the same lens as the rest of the food system,” Ms. Dorry said. “People are already thinking about that at farmers’ market. Those same things apply to fisheries and are equally important elements of sustainability.”

Farmers’ market director Linda Alley agreed. “It’s a great place to host it,” she said. “Sometimes people like to cook with ingredients they might not know about at the market.”

The chefs will be able to bring three ingredients from their own kitchens, as well as cooking utensils and pots and pans. Ms. Dorry is providing a propane grill and three-burner cast-iron stovetop; the rest of the magic is up to the chefs.

“I’ve never met the other chef so I’m looking forward to meeting him,” Mr. Graham said, taking a break from the kitchen at the Home Port. While Mr. Graham has Top Chef experience, he’s never participated in a direct contest before. “I’m excited to showcase our local seafood. We really do have world-class seafood in our backyard and we get so spoiled here we forget.”

This is Mr. Graham’s second season at the Home Port, returning from Los Angeles after missing Menemsha “dearly.” Mr. Graham is confident in his cooking abilities and local seafood available, buying directly from boats and being fluent in Island ingredients. “I’m excited to see what they’ve got to offer,” he added.

The chalkboard menu at Sidecar has an ever-changing list of local farms, almost creating a map of the West Tisbury market. Although Mr. Garell hasn’t been in a competition since culinary school at the New England Culinary Institute, he’s feeling good about Saturday. “It’s different when all eyes are on you,” he said. “But it’s a great idea, I can’t believe they haven’t done it sooner.”

Mr. Garell buys from the market every Wednesday and Saturday, and thinks his knowledge of the farms and what they’re producing will give him an advantage. “I know exactly what the farms are producing right now,” Mr. Garell said before he went to the line earlier this week. “It’s a matter of knowing the right booth to go to.”

“When people get seasonality elements it helps them also to see that there’s a cod season for example,” Ms. Dorry said. “People realize that it’s coming from the ocean, I shouldn’t be demanding the same thing all year round. It’s not a way to keep healthy.”

Through NAMA’s seafood throwdowns, Ms. Dorry wants people to shift their thinking from produce and apply it to the ocean. “The more communities we do this in, the more we have to talk about,” she said.

Seafood Throwdown begins Saturday at 10 a.m. at the West Tisbury Farmers’ Market at the Grange Hall on South Road.