Thursday, May 31, 2007

Krill fishery

Krill fishery is the commercial fishery of krill, small shrimp-like marine animals that live in the oceans world-wide. Estimates for how much krill there is vary wildly, depending on the methodology used. They range from 125–725 million tonnes of biomass globally. The total global harvest of krill from all fisheries amounts to 150 – 200,000 tonnes annually, mainly Antarctic krill (Euphausia superba) and North Pacific krill (E. pacifica).

Krill are rich in protein (40% or more of dry weight) and lipids (about 20% in E. superba). Their exoskeleton amounts to some 2% of dry weight of chitin. They also contain traces of a wide array of hydrolytic enzymes such as proteases, carbohydrases, nucleases and phospholipases, which are intense in the digestive gland in the cephalothorax of the krill.

Most krill is used as aquaculture feed and fish bait; other uses comprise livestock or pet foods. Only a small percentage is prepared for human consumption. Their enzymes are interesting for medical applications, an expanding sector since the early 1990s.

No comments: