by J. Michael Wheeler
Part of an on-going series on Sustainable Agriculture
Friends don’t let friends eat farmed fish – Seattle bumper sticker
Just as land-based farmers are working out the kinks in developing sustainable agriculture, so too are ocean-based fish farmers. Seemingly, farm fishing has all the elements of a perfect symbiotic relationship with nature: the fish are raised in their natural habitat, the dwindling wild stocks are preserved, and there is minimal disruption to the environment. The reality, until now, has been somewhat different.
Critics of fish farming cite three major issues: too many fish in too little water, the depletion of wild stocks by feeding wild fish to farmed fish, and the possibility of introduced species escaping from the nets and competing with the native species for resources.
Currently, many commercial fish farms are located in bays and inlets that are relatively shallow. The waste from these concentrated fish populations accumulates in these shallow, sheltered waters. The pollution created by too many fish in too little water threatens farmed fish stocks, and, perhaps more alarmingly, the neighboring indigenous species. Just like high-density land-based farms, these fish farms are forced to add antibiotics and other pharmaceuticals to the fish feed to prevent disease and infection.
Marine biologists think that this problem would be avoided by farming in deep ocean water: strong ocean currents move millions of gallons of seawater daily, eliminating the concentration of fish waste and thereby eliminating the need for supplements.
Farm fishing in open ocean is a much greater challenge than shallow water farming, and until recently the technology to withstand the demands of fish framing in unsheltered ocean didn’t exist.
OceanSpar, a Bainbridge Island based company (near Seattle), has developed the OceanSpar Sea Station. Fish pens are attached to a 65-foot central shaft. This shaft, the “Spar,” can be raised or lowered by filling the hollow core with air or water. This allows the stations and the fish stock to be submerged far enough below the surface to be protected from the weather and rough water. In deep enough water, the natural ocean currents keep the water from accumulating and avoiding the biological hazards of shallow water fishing.
OceanSpar’s web site tells us
Off-shore, exposed environments demand deep water capabilities, survivability in extreme storm events, and efficient feeding, harvesting and maintenance operations.
OceanSpar’s SeaStation line of off-shore fish pen solutions is the only technology proven capable of handling the demands of off-shore aquaculture operations…Our SeaStation fish pen systems are customized to the unique site and species characteristics…SeaStation fish pens are the secure, economical solution for open ocean aquaculture.
How about taste? Foodies criticize farmed fish for its bland taste compared to wild caught. In our next article we’ll explore how a fish farm in Hawaii is wowing restaurants, diners, and fish farm critics.
Links:
OceanSpar
Greenpeace article critical of fish farming
The Marine Conservation Society (MCS) article on Sustainable Seafood
Buy a Wild Caught hat, click here.