"The Blue Food Cookbook: Delicious Recipes for a Sustainable Future" from Maine-based author, sustainability expert and chef Barton Seaver and food television personality Andrew Zimmern, offers a comprehensive primer on sustainability issues and seafood cookery.

But the book is also a call to action, for the sake of the planet and public health, with a straightforward ask of its readers. As Chick-fil-A might put it, "Eat Mor C-Food." Seaver instead riffs on the longstanding National Livestock and Meat Board slogan.

"Please decide that seafood is what's for dinner, and feel good about that," he said. "Just deciding that is a really big step forward for so many Americans."

While Seaver today calls himself a "seafood evangelist," he was far more skeptical of the health of global fisheries 20 years ago. He offers his previous stance on salmon farming as an example. "I was a proud, card-carrying member of the 'farmed and dangerous' crowd, vociferously advocating against the farming of salmon."

But Seaver said "radical change and innovation" over the past couple of decades altered his outlook. He cited improvements to how salmon feed is formulated and sourced, more eco-friendly farm locations and stronger animal welfare practices.

"Ultimately, my position was a little short-sighted. The industry has advanced. It's a new era."

"The book's message is simple but urgent," said Zimmern, who responded to questions by email. "If we eat more from the water, wisely from the water, then we can nourish ourselves and heal the planet."

"The Blue Food Cookbook" -- the ninth of Seaver's books, which also include "For Cod and Country" and "The Joy of Seafood" -- arose from Seaver and Zimmern's work on the 2024 PBS docuseries, "Hope In The Water." Like the cookbook, the shows were spearheaded by the science-based communications initiative Fed By Blue. The series explores the work of fishermen, aqua farmers and scientists aiming to feed the planet while saving the oceans; one episode features Vertical Bay owner Andrew Peters talking with Martha Stewart about scallop farming in Maine.

"Blue food" is a term coined at the United Nations Food System Summit in 2021. Zimmern explained that it's meant to frame seafood in a larger, planetary context that includes how it affects nutrition, food security, biodiversity and climate resilience.

"Calling it 'Blue Food' invites policy makers, scientists and chefs to think of the blue economy as integral to solving food security and climate problems," Zimmern said. "Blue Foods provide high-quality protein and essential micronutrients while using far less land and freshwater than most terrestrial foods."

Seaver and Zimmern have known each other for decades, and collaborated over the course of about 18 months on the cookbook project. Along with an overview on sustainability issues and best practices, the book includes technique and equipment tips, advice for buying and storing seafood, and 145 recipes for shellfish, seaweed and fish across the spectrum -- from lobster, swordfish and octopus to tilapia, canned tuna and pink salmon.

The dishes draw inspiration from the authors' global travels, professional cooking experience and the many seafood meals they've cooked in their home kitchens. Seaver, who lives with his wife and two sons in south Freeport, said Mainers have an advantage over people in many other parts of the country when it comes to buying sustainable, high-quality seafood.

"Most of the places that Mainers shop for seafood are doing a really great job," he said. "With what you'll find available -- whether it's from Shaw's, Hannaford, Harbor (Fish Market) or Browne (Trading Market) -- you're going to have great quality options."

Specialty fishmongers are no longer the only place to find pristine, responsibly sourced fish and shellfish. Seaver said the seafood sections at Costco and Walmart are actually among the best sources. "No joke. I'm constantly surprised and impressed by the thought and care that has gone into getting sustainable products on their shelves, and also the quality of what's there."

Of course, cost is a large part of what keeps many people from eating seafood more regularly. Per pound, it's often considerably more expensive than chicken, pork or even beef. Still, less costly and smart-sourced seafood options are widely available.

"Seafood is actually the only sustainable food I can find in most gas stations in Maine, in the form of a can of tuna or sardines," Seaver said. He argued that there are also hidden costs for land animal proteins. We pay for our meat not only at the store, but through taxes that fund farm subsidies, "and again in the hospital, when the Western diet inevitably sends us there."

Seaver recognizes that this a "privileged" argument, and it's not something he expects to hold water with people struggling to find ways to feed their families amid ever-increasing food costs. But "The Blue Food Cookbook" offers practical strategies for home cooks to enjoy seafood more sustainably and also more affordably:

∙Embrace frozen seafood. It has an outdated reputation for being far inferior to fresh. Seaver and Zimmern note that frozen food technology has come a long way since Clarence Birdseye pioneered it in the 1920s.

Today's flash-freezing methods are much less likely to damage the food's cellular structure, better preserving flavor and texture. Acoustic freezing technology now being developed -- using high-frequency sound waves to control the size of ice crystals -- promises a quantum leap in frozen food quality in the years ahead.

"I have had my mind absolutely blown by the quality of frozen seafood, more and more," Seaver said.

Frozen seafood is also usually cheaper than its fresh counterparts, and far less perishable: A 2015 Johns Hopkins study found that more than a billion pounds of seafood is wasted every year by consumers discarding their spoiled or uneaten seafood at home.

∙Right-size your portions. Most people only need the calories, protein and micronutrients in a four-ounce portion of seafood. "You don't need to eat half or three-quarters of a pound of salmon," Seaver said.

The book's recipes split the difference between our sometimes super-sized portions and what a dietician might recommend, and call for about 5 ounces per person.

∙Eat lower on the seafood chain. "Eating underutilized species, like mussels, sardines, clams and seaweeds, eases pressure on overfished stocks and supports smaller, more sustainable fisheries," Zimmern said.

Small fish and bivalves breed much more prolifically than the larger fish that eat them. "A pound of tuna and a pound of anchovies are equally good at satiating us, but their overall impact on the environment is radically different," the book states, adding that small fish like anchovies, mackerel, herring and sardines are also very high in healthy omega-3 fatty acids.

Seaver suggests that locally, we'd all benefit by eating more bivalves. Maine's world-class farmed mussels, oysters and scallops are familiar, highly sustainable foods that represent the next chapter of the state's seafood industry.

"We live in the Napa Valley of bivalves," Seaver said. "Put a Bangs Island or Maine Gold mussel against any other mussel from anywhere else in the world -- we have got something going on here that just hits better."

∙Try new kinds of seafood. Narrow consumer preferences have been a major factor in overfished seafood populations. "The Blue Food Cookbook" asserts that salmon, shrimp and canned tuna alone account for 60 percent of America's seafood consumption.

"Most Americans don't realize that species like mackerel, mussels, or catfish can be cheaper, more sustainable, and often tastier than the 'Big Five' of salmon, shrimp, tuna, crab and cod," Zimmern said.

The book includes a section that breaks down seafood species by category -- e.g., flaky white fish; salmon family; steak fish; bivalves, shellfish and cephalopods -- so that cooks can be flexible at the market: If the halibut your recipe calls for doesn't look fresh, go with another flaky white fish that's better looking (and cheaper), such as pollock, hake, haddock or catfish.

"The Blue Food Cookbook" doesn't flatly label certain seafood species as "sustainable," since the designation is fluid and subject to change. Instead, the book suggests readers check recommendations offered by seafood industry watchdog groups like the Aquaculture Stewardship Council (ASC) and Marine Stewardship Council (MSC), and the Seafood Watch guide from the Monterey Bay Aquarium.

In the end, Seaver said he's less concerned about the state of any specific fishery right now. Instead, he's impressed by how well fisheries in general are being managed.

"I have come to trust the system," he said, "and I know that the arc of management bends toward sustainability."

Steamed Black Bass with Ginger, Garlic and Scallions

If you don't have access to whole fish, you can steam fillets or portions of black bass.

Serves 4 to 6

2 whole black bass, 2 to 3 pounds each, cleaned and scaled, head-on

Salt

1 (4-inch knob) fresh ginger, half very thinly sliced, half cut into very fine threads

3 garlic cloves, thinly sliced

2 cups Shaoxing cooking wine or sake

1/4 cup toasted rapeseed oil (available at Asian markets or online) or peanut oil

1 bunch scallions, sliced into fine threads about 4 inches in length

1/4 cup aged natural soy sauce

Special equipment: bamboo steamer

Wash and dry the fish very well. Season the fish with salt inside and out and set aside. You can score it if you like. Place the sliced ginger and garlic inside the fish cavities.

Place 1 ½ cups of the wine into the base of a steamer and add a quart or so of water, along with any ginger and scallion trimmings you have left. Place the fish on small plates and steam for 12 to 15 minutes, until cooked through. Use an instant-read thermometer to take the temperature along the backbone. It should read 130 degrees F when done.

While the fish is steaming, heat the oil in a small pot over medium heat.

When the fish is done, slide it onto a large platter. Place the ginger threads and scallion over the fish. When the oil is almost smoking, drizzle it over the fish along with the remaining wine and the soy sauce.

Scallop Aguachile

Andrew Zimmern fell in love with aguachile years ago on one of his first trips to coastal Mexico. This recipe is inspired by the aguachile dishes of San Diego Chef Claudette Zepeda.

Serves 4

8 ounces tomatillos, chopped

1/2 bunch cilantro, chopped

1/3 cup chopped scallions

1 ½ teaspoons honey

1 serrano chile, stemmed

1 cup coconut water

1/4 cup lemon juice (about 2 lemons)

1/4 cup lime juice (about4 limes)

1/2 large English cucumber, chopped (about 1/2 cup)

Salt

1 pound fresh jumbo dry-pack sea scallops, sliced across in half or thirds

1 teaspoon toasted fennel seeds

1 carrot, steamed and cooled, thinly sliced into rings (about 1/2 cup)

1 small Persian cucumber, thinly sliced into rings (about 1 cup)

1 shallot, thinly sliced into rings (about 1/4cup)

1/2 cup mint leaves (from about 4 sprigs) and mint flowers if you have them, to garnish

1/2 cup cilantro leaves (from about 4 sprigs), to garnish

1 cup edible flowers, to garnish

Combine the tomatillos, chopped cilantro, scallions, honey, chile, coconut water, lemon and lime juices, English cucumber, and salt to taste in a blender and blend until homogenous. Strain though a fine-mesh strainer or a strainer lined with cheesecloth and discard the solids. Season the liquid again as needed, then cover and refrigerate for at least 2 hours.

Place 4 to 5 ounces of aguachile into 4 ice-cold, low-sided wide bowls. Divide the scallops among the bowls. Sprinkle each with the fennel seeds and salt. Arrange the carrot discs, Persian cucumber rings, and shallot rings around each bowl. Arrange the mint and cilantro leaves and flowers around the bowls. Serve immediately.