Just as land based food is in jeopardy from Climate Destabilization and the seas are overfished, tunicates promise to help out. They can be eaten directly or fed to farmed salmon (yum).
The yellowish, slimy growth that many of us have come across on ropes that have lain in seawater is the marine organism known as tunicates.
Tunicates are basically living filter tubes that suck bacteria and other microorganisms into one end and excrete purified water out the other end. This is how tunicates feed -- at the very bottom of the food chain and without competing directly with fish or other marine animals higher up in the chain.
Tunicates grow very quickly and year-round. Found in every ocean, they particularly thrive in cold, nutrient-rich waters such as those around the quays and coastal rock slopes of Western Norway.
Since there are no marine predators feeding on tunicates, some 2 500 to 10 000 individuals can grow undisturbed in 1 m2 of ocean surface area.
Other than the Japanese and Koreans, who eat tunicates, no one has paid them much attention until now.
The production method resembles the cultivation of mussels. At a facility in a small finger of a fjord, long plastic sheets are anchored to the seabed and held vertical by buoys. Between these sheets flows seawater teeming with the microorganisms tunicates need.
Norway is the world's largest producer of salmon feed, and there is a huge demand for more marine proteins as feed ingredients, but the limit has already been reached in industrialised fishing.
One major challenge facing feed producers is to produce salmon feed containing omega-3 fatty acids, which the fish need but do not generate. The bulk of omega-3 in salmon feed presently comes from the fisheries industry. Dried tunicates contain 60 per cent protein and are rich in omega-3. Perhaps just as importantly, salmon find them tasty as well. [emphasis mine]