They also contain traces of a wide array of hydrolytic enzymes such as proteases, carbohydrases, nucleases and phospholipases, which are concentrated in the digestive gland in the cephalothorax of the krill.

Krill are small animals, considered a type of zooplankton, and hence need to be fished with fine-meshed plankton nets.

Such nets pose several problems: they tend to clog fast, and they have high drag, producing a bow wave that deflects the krill to the sides.

Furthermore, fine nets increase unwanted bycatch, such as fish fingerlings, which might have unforeseen side-effects on the ecosystem, even though large krill aggregations tend to be monospecific.

When the full net is hauled out of the water, the organisms compress each other, resulting in great loss of the krill's liquids.

Experiments have been carried out to pump Antarctic krill, while still in water, from the cod end of the net through a large tube on board.

This method had already been used by the small fishing boats in Japanese waters; it increases the capture capacity and the processing rate of krill.

[7] [8] Krill must be processed within one to three hours after capture due to the rapid enzymatic breakdown and the tainting of the meat by the intestines.

Krill as a food source is known to have positive effects on some fish, such as stimulating appetite or resulting in an increased disease resistance.

Medical applications of krill enzymes include products for treating necrotic tissue and as chemonucleolytic agents.

All throughout the decade, preparatory activities were carried out, resulting in small catches of a few tens of tonnes per year.

Its purpose is to regulate the fishery in the Southern Ocean to ensure a long-term sustainable development and to prevent overfishing.

Still, the CCAMLR is criticized for having defined its catch limits too generously, as there are no precise estimates of the total biomass of Antarctic krill available and there have been reports indicating that it is declining since the 1990s.

In the 1970s, the krill fishery expanded drastically and began to use also one- or two-boat seines, which can catch swarms as deep as 150 m (490 ft).

In Canada, fishing for E. pacifica takes place in the Strait of Georgia off British Columbia; there is a government-imposed catch limit of 500 tonnes per year.

Fisheries targeting the Northern krill (Meganyctiphanes norvegica), a medium-sized krill reaching body lengths of more than 4 cm (1.6 in), as well as Tysanoessa raschii (2 cm) and T. inermis in the Gulf of St. Lawrence and on the Scotian Shelf have been proposed, but didn't get beyond early experimental stages.