5 WAYS SUBMERSIBLE PENS CAN INCREASE YOUR FARM VALUE

Submerged production systems have become a prominent production method for marine aquaculture, mainly for farmers looking to escape storms and the rough wave environment found at the surface of exposed locations. Submerging pens and grids is proven to be an effective way to reduce damage to system components and has opened new high-energy sites for production, but there are additional significant reasons to submerge pens and infrastructure.

Having access to water above and below a thermocline can save whole crops of fish. The University of New Hampshire is producing steelhead trout near the Isles of Shoals, NH. They are having a lot of success but are seeing high mortality during the summer months due to heat stress. They are looking at submerging their pens by 15m to get their fish below the thermocline and into water 4°C cooler which would alleviate the mortality associated with the high summer temperatures. By using submersible pens, the acceptable range for farming salmonids in US waters may be expanded from mid-Maine to Massachusetts on the East coast and from Washington State to the California bight on the West coast (figure 1).

Harmful algal blooms (HABs) typically occupy the top 5 - 15 meters where light can penetrate. HAB events caused massive mortality in Norway during the summer of 2019 and are expected to be more prevalent in the future according to climate change models. Submerged pens can offer protection from these events by moving fish below the most dangerous depths.

Multiple sources of value creation will be explored during this presentation, including using submersible pens and technology that take advantage of vertical current profiles, reduce parasites, and decrease visual impacts, vandalism and poaching.