Fifteen years ago, aquaculture looked like the savior of New England’s historic but declining fishing industry. Instead of chasing diminishing stocks of fish around the Gulf of Maine, those who wanted to make a living harvesting from the saltwater could grow their own in bays and harbors close to home. It seemed like the perfect, conservation-sensitive solution for Maine, combining centuries of tradition with modern technology and marketing.

But the fledgling industry stumbled after bumping up against problems with disease, pollution and public opposition to its encroachment on open waters. A major blow came when the native Atlantic salmon was listed as a federally endangered species, which meant salmon farmers had to stop farmed fish from escaping. Then, many locally based businesses were gobbled up by foreign-based companies, and employment and production dropped precipitously.

Though the industry has not been in the news as much as when it was new, aquaculture is very much alive in Maine and rebuilding, with the assistance of a serious research and development institution, the Center for Cooperative Aquaculture Research, in Franklin. Currently, salmon are being raised at 40 sites around the state, managed by 13 farms. The region with the most intensive salmon farming is Cobscook Bay in Washington County. Cod, the historic New England staple fish, is being raised in Frenchman’s Bay, and shellfish farming is seeing steady growth along the midcoast.

The future is promising, says Sebastian Belle, executive director of the Maine Aquaculture Association. His confidence is fueled in part by the rise of research-based practices, which emerged after the initial gold rush phase that often accompanies a new venture like aquaculture. The early days were marked by trial and error, and a kind of arrogance, Mr. Belle admits. Those proposing pens for areas of the coast were often dismissive of residents’ concerns, he said. That and other objectionable practices have changed, in part because of legal requirements due to the native salmon endangered species listing.

Proposed farm sites are considered more judiciously, feed is now 40 percent vegetable based, allaying concerns about the health of the product, each year’s stock is kept far away from the previous year’s to prevent the spread of disease, and sites are on a three-year rotation.

In addition to the new research center, the University of Maine also is bringing science to fish farming. Dr. Ian Bricknell, a veteran of the mature aquaculture industry in his native Scotland, is researching vaccines for farm-raised fish at UMaine. And the university now offers a bachelor’s degree in aquaculture. Dr. Bricknell notes that the research center in Franklin is better than similar facilities in Chile and Norway, where aquaculture has thrived for years.

Yet challenges remain. Chief among them is persuading bankers to lend money for fish farming endeavors. A state revolving loan fund could help fishermen displaced from off-shore harvesting start small farms to support their families, Mr. Belle says. The local foods movement could help revive fish farming. And perhaps most helpful would be a campaign to again persuade the public of the benefits of consuming farm-fresh fish.