The capelin fisheries are managed by a simple catch rule The Marine Research Institute, often in cooperation with fishing boats, assesses the size of the spawning stock with acoustic methods. Fisheries are then allowed if more than 400 thousand t of mature fish are found, if not the fishery is closed for that season. If more than 400 thousand t are found the quota is set to the amount exceeding 400 thousand t. As an example, if the spawning stock is measured at 600 thousand t, the quota is set to 200 thousand t. This is to ensure that the spawning stock will not be compromised and enough is left behind as important food for other marine animals.