The available data on shark fisheries is considered to be rather limited and questionable. Even if FAO statistics represent the most exhaustive data on world fisheries, it is not possible to determine the exact volume of shark from the total chondrichthyan catches. As can be seen in Table 1, there are problems of species identification and lack of species-specific reporting. Many of the estimated 465 shark species are small, deep-water and seldom met or caught. About 100 species are encountered in commercial fisheries throughout the world. FAO statistics report figures for only 29 species of sharks, from individual species to orders, plus the group of various sharks nei (Selachimorpha (Pleurotremata)) FAO data are compiled from information supplied by the fishery agencies of individual countries. National reporting by species is rare and generally occurs only in the few cases where sharks are included in existing management plans. Often countries lump together all shark species or report catches of sharks and batoid fishes within the single category of "Elasmobranchii unidentified", or simply provide FAO with summary information from these fisheries. Approximately half of all catches and landings, and the largest increases in landings in recent years, are reported in the category of unidentified Elasmobranchii.
According to FAO statistics, chondrichthyans represent only a minor group in terms of catches. In 1997 they accounted for only 0.65% of total world catches and 0.85% of total world captures. Total chondrichthyan catches have grown considerably, from 271 800 tonnes in 1950 to a record of 804 000 tonnes in 1996. This growth was fairly regular, with some periods sluggish (early 1950s and most 1970s) and some sustained increases (1955-73 and 1984-96). In 1997 catches were 789 900 tonnes, a 1.8% decrease as compared to 1996.