Seafood For Thought

2017-08-16 04:54:43

Net pen aquaculture in deep coastal waters. Photo Credit: NOAA

Net pen aquaculture in deep coastal waters. Photo Credit: NOAA

The world’s oceans possess vast, untapped potential for sustainable aquaculture, say UCSB marine scientistsCovering 70 percent of Earth’s surface, the world’s oceans are vast and deep. So vast, in fact, that nearly every coastal country has the potential to meet its own domestic seafood needs through aquaculture. In fact, each country could do so using a tiny fraction of its ocean territory.

So finds a study led by scientists from UC Santa Barbara and including researchers from the Nature Conservancy, UCLA and the National Oceanic and Atmospheric Administration. Their research, published today in the journal Nature Ecology and Evolution, demonstrates the oceans’ potential to support aquaculture. Also known as fish farming, the practice is the fastest-growing food sector, and it’s poised to address increasing issues of food insecurity around the globe.

According to the study, among the first global assessments of the potential for marine aquaculture, the world’s oceans are rife with aquaculture “hot spots” that provide enough space to produce 15 billion metric tons of finfish annually. That is more than 100 times the current global seafood consumption.

More realistically, the researchers note, if aquaculture were developed in only the most productive areas, the oceans could theoretically produce the same amount of seafood that the world’s wild-caught fisheries currently produce globally, but in less than 1 percent of the total ocean surface — a combined area the size of Lake Michigan.

The United States, for example, has enormous untapped potential and could produce enough farmed seafood to meet national demand using only 0.01 percent of its exclusive economic zone, Gentry noted. Given that the U.S. imports more than 90 percent of its seafood, aquaculture presents a powerful opportunity to increase domestic supply and reduce the nation’s seafood trade deficit, which now totals over $13 billion.

To determine aquaculture’s global potential, the researchers identified areas where ocean conditions are suitable enough to support farms. They used synthesized data on oceanographic parameters like ocean depth and temperature and the biological needs of 180 species of finfish and bivalve mollusks, such as oysters and mussels.

The research team ruled out places that would come into conflict with other human uses, such as high shipping zones and marine protected areas, and excluded ocean depths that exceed 200 meters, following current industry practice to keep their assessment economically realistic. Their analysis did not consider all possible political or social constraints that may limit production.

There’s so much area available that there’s a lot of flexibility to think about how to do this in the best way for conservation, economic development and other uses.