People who want to eat fish only if it’s caught in an ecologically benign way should shop for fish caught by Mainers.

That’s the message from the Portland-based Gulf of Maine Institute as it begins an effort to create markets for under-used fish species. Seafood caught in the Gulf of Maine is among the most sustainably harvested seafood in the world, says Jan Levin, manager of the organization’s sustainable seafood program.

Long under fire for practices that destroyed habitat and depleted stocks, New England’s fishing industry has made an unappreciated turnaround because of changes in management and methods, Levin and others say.

The past decade has brought major innovations to trawling gear that reduce environmental damage. For example, haddock nets have been adapted to the behavior of fish. The nets capture haddock, which swim upward when caught, and allow cod, which swim downward, to escape.

Fishing regulations have increased nets’ minimum mesh size from 4 inches 30 years ago to 6.5 inches today, making New England’s net mesh sizes the largest in the world, said Levin. The larger mesh has dramatically reduced the unintentional catch of untargeted fish species.

Today, many of the heavily regulated Gulf of Maine groundfish stocks are rebuilt or are on the rebound. “If it is caught by a Maine fisherman, you should feel really good about eating it,” said Levin.

The institute has been working to help restaurants and food retailers adopt strategies that reward responsible fishing practices.

“When you have a thriving seafood industry, fishermen have the capacity to invest in equipment that reduces by-catch, engines that reduce fuel consumption and practices that improve the quality of the fish so they can catch less and make the same amount of money,” Levin said.

Hannaford Supermarkets and its parent company, Delhaize America, which also operates Sweetbay, Food Lion and Bottom Dollar Food, announced Thursday that they will sell only seafood that is caught by standards that ensure its sustainability.

The new program is expected to have an impact, since the 176 Hannaford stores alone sell about 18 million pounds of fresh fish a year.

The company developed its policy with help from the Gulf of Maine Institute. The company is requiring suppliers to demonstrate that the 4,000 to 5,000 fresh, frozen and canned seafood products it sells come from well-managed fisheries with detailed management plans.

George Parmenter, corporate responsibility manager for Delhaize America, said customers will get more information about the source of their seafood and may see more locally caught fish in Hannaford seafood cases.

“The good news is that what we are doing is in line with the retail and seafood industry, so suppliers and processors are moving this way as well,” said Parmenter.

Portland restaurant owners, who have long promoted fresh, locally grown ingredients, are joining the effort.

Charles Bryon, owner of The Salt Exchange restaurant on Commercial Street, decided to offer hake, an under-used Gulf of Maine species, on his menu and donate $2 from each hake entree sold to the research institute.

Bryon said a seminar that the institute sponsored to reacquaint restaurant owners and chefs with Maine-caught fish led to several changes at the restaurant.

Michelle Corry, owner of the restaurant 555 on Congress Street, started selling ocean-themed drinks a couple of months ago and donating $1 from each drink sale to the institute, for projects related to sustainable fishing.

Portland’s Harbor Fish Market has stayed away from overfished species for years, said Ben Alfiero, who owns the market with his brothers. The market will not sell shark, bluefin tuna or wolf fish.

Alfiero said it’s good for business to encourage sustainable harvesting, and his customers now depend on it. “Most people really care,” he said.

The Midcoast Fishermen’s Cooperative was banking on the growing demand for sustainably harvested fish when it was formed by a dozen fishermen in Port Clyde in 2007. The co-op opened its own fish processing plant the next year.

From the outset, the group marketed itself as a sustainable operation, to appeal to the growing appetite for locally caught fish and to protect its resource.

“We wanted to stop discarding so many fish and lighten up the gear to have less impact on the habitat,” said Glen Libby, president of the co-op, which sells its fish under the Port Clyde Fresh Catch brand.

Last year, the co-op started the first community-supported fisheries shares operation in the nation, and possibly the world. The idea has been picked up in other parts of the country.

Port Clyde Fresh Catch fish are sold at farmers markets and to restaurants as far south as Boston. The co-op’s payroll has jumped from two people last year to 23 today.

Libby said the quality of the product is the secret to the co-op’s success.

Staff Writer Beth Quimby can be contacted at 791-6363 or at:

bquimby@pressherald.com