Credit: George Danby

I am both dismayed and encouraged by the debate around the proposal for a land-based salmon farm in Belfast. Dismayed because of the misinformation and emotional statements made at a public hearing last month, such as “The ocean is already collapsing,” and “Nordic is for the destruction of the ocean because they’re a fish farm.” But I am also encouraged because “a couple of speakers” reportedly “seemed to indicate their willingness to move forward and find out more hard facts,” as the BDN reported.

First, I offer some background on salmon farming: The history of salmon aquaculture unfolded during my life and career. The first farmed salmon appeared when I was a graduate student. It was once thought it would be suitable for fishing families, but large investments were needed in research and development. Meanwhile, the global demand for farmed salmon skyrocketed everywhere.

In the 1990s, as industrial salmon farming expanded, net pens developed in bays and fjords, first in Norway, then in Chile, Canada and Down East Maine. These were “open systems” where waste, feeds, dead fish and farming debris were released, and pens occasionally failed, spilling farmed fish into the ocean causing “biological pollution.” Coastal landowners vehemently complained that their views were being invaded by pens, feeding barges and the “plastic spaghetti” on the water surface needed to feed fish.

But with research and development, sophisticated feeds and new technologies were invented, and food conversion ratios have dropped to 1:1. That’s right, just one pound of feed can produce one pound of salmon. (It takes seven pounds of feed to produce one pound of beef, which also produces much more pollution.)

In the 1990s, antibiotics were added to control diseases. No more. Vaccines have been developed for the major diseases that plague salmon, so today each fish is vaccinated. No antibiotics needed. Again, to draw a comparison with industrial meat production, antibiotics are used routinely in cattle — and not to control disease but promote growth.

Now in the 2010s, after more than 30 years of research and development, the science of recirculating aquaculture systems on land is finally here, making it possible to farm fish without the use of net pens in the ocean. Recirculating aquaculture systems are more costly, but they enable fish farms to be part of a true recycling aquaculture economy where the wastes may become more valuable than the fish fillets themselves, as they are used in new products from animal feed to pharmaceuticals.

But there is a much larger issue for all of humanity to face. Fish account only for 15.7 percent of global animal protein consumption. By 2050, we’ll need to increase food production by about 50 percent to 75 percent to feed a planet of 10 billion. If we expect to get this protein from the land, most of the world’s last great natural areas will be destroyed by agriculture’s expansion. Sustainable intensification just won’t do it. We must find ways to sustainably farm aquatic species to save Mother Earth.

The ocean is not “collapsing” due to aquaculture. On the contrary, aquaculture needs high water quality, or its products have little value. The major coastal ocean problems are sewage and trash. Billions of gallons of wastewaters containing a witch’s brew of personal health care products and plastics are causing over fertilization and coastal acidification as well as other trends that scare even the most staid, conservative research scientists.

We have an extraordinary opportunity for Maine communities. Land-based aquaculture can create hundreds of knowledge-based jobs. Our universities could be global centers of excellence in education, research and business outreach. And land-based aquaculture could expand inland for trout and Arctic charr of which Maine has special varieties found nowhere else.

Americans import more than 90 percent of the seafood we eat, much of which comes from poorly regulated aquaculture farms elsewhere. Don’t let those who jump on junk science websites or express a simple dislike of farmed fish distract us from the real opportunities. Dirigo aquaculture, Maine.

Barry A. Costa-Pierce is editor-in-chief of the journal Aquaculture, the executive director of UNE NORTH and a professor of marine sciences at the University of New England.

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