Scientific undertakings rather than commercial pursuits are the predominate human activity in Antarctica. Fishing off the coast and tourism, both based abroad, account for Antarctica's limited economic activity. Antarctic fisheries, targeting three main species - Patagonian and Antarctic toothfish (Dissostichus eleginoides and D. mawsoni), mackerel icefish (Champsocephalus gunnari), and krill (Euphausia superba) - reported landing 141,147 metric tons in 2008-09 (1 July - 30 June). (Estimated fishing is from the area covered by the Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR), which extends slightly beyond the Antarctic Treaty area.) Unregulated fishing, particularly of Patagonian toothfish (also known as Chilean sea bass), is a serious problem. The CCAMLR determines the recommended catch limits for marine species. A total of 37,858 tourists visited the Antarctic Treaty area in the 2008-09 Antarctic summer, down from the 46,265 visitors in 2007-08 (estimates provided to the Antarctic Treaty by the International Association of Antarctica Tour Operators (IAATO); this does not include passengers on overflights). Nearly all of them were passengers on commercial (nongovernmental) ships and several yachts that make trips during the summer.