Technical Notes: Trends in Marine and Inland Fisheries Capture by Species VARIABLE DEFINITIONS AND METHODOLOGY Fisheries capture data refer to the nominal catch of fish, crustaceans, molluscs, aquatic mammals, and other aquatic animals taken for commercial, industrial, recreational and subsistence purposes from marine, brackish, and inland waters. The harvest from aquaculture and other kind of farming are excluded. Aquatic plants include: brown seaweeds, red seaweeds, green seaweeds, and miscellaneous aquatic plants. For more detailed information, please refer to the original source at http://www.fao.org/waicent/faostat/agricult/fishitems-e- e.html. Crustaceans include: freshwater crustaceans, sea-spiders, crabs, lobsters, spiny-rock lobsters; squat lobsters, shrimps, prawns; krill, planktonic crustaceans; and miscellaneous marine crustaceans. For more detailed information, please refer to the original source at http://www.fao.org/waicent/faostat/agricult/fishitems-e-e.html. Diadromous fish include: sturgeons, paddlefishes, river eels, salmons, trouts, smelt, shads, and miscellaneous diadromous fishes. For more detailed information, please refer to the original source at http://www.fao.org/waicent/faostat/agricult/fishitems-e-e.html. Freshwater fish include: carps, barbels and other cyprinids; tilapias and other cichlids; and miscellaneous freshwater fishes. For a more detailed listing of the species mentioned above, please refer to the original source at http://www.fao.org/waicent/faostat/agricult/fishitems-e-e.html. Marine fish include: flounders, halibuts, soles; cods, hakes, haddocks; redfishes, basses, congers; jacks, mullets, sauries; herrings, sardines, anchovies; tunas, bonitos, billfishes; mackerels, snoeks, cutlassfishes; sharks, rays, chimaeras; and miscellaneous marine fishes. For a more detailed listing of the species mentioned above, please refer to the original source at http://www.fao.org/waicent/faostat/agricult/fishitems-e-e.html. Data include all quantities caught for both food and feed purposes but exclude discards. The harvest of fish, crustaceans and molluscs are expressed in live weight, that is the nominal weight of the aquatic organisms at the time of capture. Data are given in thousand metric tons. Aquatic organisms included in the FAO FISHSTAT capture production database have been classified according to approximately 1290 commercial species items, further arranged within the 50 groups of species constituting the nine divisions of the FAO International Standard Statistical Classification of Aquatic Animals and Plants (ISSCAAP). Most fisheries statistics are collected by FAO from official national reports. When these data are missing or considered unreliable, FAO estimates fishery production based on regional fishery organizations, project documents, industry magazines, or statistical interpolations. Fishery production statistics were revised completely by FAO in the 1990s. At this time, FAO estimated missing data points, updated taxonomical classifications, and discriminated more clearly between aquaculture and capture fisheries production. Fisheries production statistics typically refer to the calendar years (January 1 to December 31) with exception of data from Antarctic waters, which use a split year (July 1 to June 30). FREQUENCY OF UPDATE BY DATA PROVIDERS FAO publishes updated data sets annually for FishStat. The most recent updates incorporated by WRI are from May, 2003, and include fisheries data through the year 2001. DATA RELIABILITY AND CAUTIONARY NOTES While the FAO data set provides the most extensive, global time series of fishery statistics since 1970, there are some problems associated with the data. Funding for the development and maintenance of fisheries statistics at the national level has been decreasing in real terms since 1992, while the demand is growing for a variety of global statistics on discards, fish inventories, aquaculture, and illegal activites. Country-level data are often submitted with a 1-2 year delay, and countries are declaring an increasing percentage of their catch as "unidentified fish". As a result, species- item totals frequently underestimate the real catch of individual species. Stock assessment working groups can more accurately estimate the composition of a catch; however, due to financial constraints, these groups are rare, especially in developing countries. Statistics from smaller artisanal and subsistence fisheries are particularly sparse. FAO states that "general trends are probably reliably reflected by the available statistics...but the annual figures and the assessments involve a certain degree of uncertainty and small changes from year to year are probably not statistically significant." These statistics provide a good overview of regional fisheries trends. However, when reviewing the state of fisheries stocks, evaluating food security, etc., these data should be used with caution and supplemented with estimates from regional organizations, academic literature, expert consultations, and trade data. For more information, please consult Fishery Statistics: Reliability and Policy Implications, published by the FAO Fisheries Department and available on-line at http://www.fao.org/fi/statist/nature_china/30jan02.asp. SOURCE Fishery Information, Data and Statistics Unit, Food and Agriculture Organization of the United Nations (FAO). 2003. FISHSTAT Plus: Universal software for fishery statistical time series, Version 2.3 (available on-line at http://www.fao.org/fi/statist/FISOFT/FISHPLUS.asp); Total production dataset. Rome: FAO.