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. Trawling must hence be done at low speeds. Additionally, fine nets are delicate, and the first krill nets designed exploded while fishing through the krill schools. 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.