The collection of various catch statistics for tuna and tuna-like species has been carried out by various regional and national institutions for specific species and areas. Such statistics with a geographical resolution of 5° x 5° rectangle or higher were provided to the Marine and Inland Fisheries Service (FIRF) of FAO's Fisheries Department (FI) for the specific purpose of preparing this Atlas. This provision was conditional on FIMF not releasing the data separately by country, but only in the aggregated format presented in the Atlas.
This Atlas, prepared by Fabio Carocci and Jacek Majkowski of the Marine and Inland Fisheries Service (FIRF), Fisheries Department (FI), Food and Agriculture Organization of the United Nations (FAO), is the result of the collaboration among numerous institutions and scientists. The following institutions provided data on tuna and billfish catches:
Australian Fisheries Management Authority (AFMA)
Commission for the Conservation of Southern Bluefin Tuna (CCSBT)
Indian Ocean Tuna Commission (IOTC)
International Commission for the Conservation of Atlantic Tunas (ICCAT)
Inter-American Tropical Tuna Commission (IATTC)
National Marine Fishery Service (NMFS)
Secretariat of the Pacific Community (SPC)
Western and Central Pacific Fisheries Commission (WCPFC)
The authors would like to thank, for the provision of catch data, Christofer H. Boggs (NMFS, Honolulu), Miguel Herrera (IOTC), Michael G. Hinton - Nick Vogel (IATTC), Mauricio Ortiz - Carlos Palma (ICCAT), Timothy Lawson (SPC), Samuel Pooley (NMFS, Honolulu), Darryl Tagami (NMFS, Honolulu), Bob Kennedy - Simon Morgan (CCSBT), Peter Williams (WCPFC), Thim Roed Skousen (AFMA).
Collection Method: Approximately every 2 years, the Atlas is being updated by incorporating the catch data that become available from the websites of the data providers listed in the Data Source section. Before the publication, the data are reviewed to eliminate any overlap among the sets available from the different data providers. Also, the original data are adjusted (including combining of some data) so their resolution and format are compatible with those of the Atlas. Such data are supplemented, as required, by those from national institutions.
Processing Method: Because not all catches are recorded in logbooks with their locations, the resulting data are raised, by the institutions responsible for collating such data, to total catches for some fisheries where such a raising can provide adequate approximations. These raised catches are referred in the Atlas as spatial catches or 5° by 5° catches. Because locations and/or season of some catches may be unknown or poorly known, the Atlas may not account for them. Also, in some area, the location of catches from industrial fisheries for tuna and tuna-like species are not available to the public domain. Consequently, they may be significantly different from those of nominal catches available from FAO Global Capture Production database as well as from those available from regional international and national institutions.
Validation Mechanism: Figures 1 to 4 show the geographical areas where longline, pole and line, purse seine and other gears catches of the principal market tunas and the billfishes considered in the Atlas are reported. As longline and, to a lesser extent, pole and line, fisheries target both temperate and tropical tunas and tuna-like species (not necessarily with the same fishing gear configuration), their areas of operation are largest. The purse seine fisheries operate mostly in the tropics. Figures 5 and 6 show the geographical distribution of catches for the last 5 years (2005-2010) presented in the Atlas by fishing gears and by species.
Trends of catches
Figure 7 shows the global combined spatial catches for all the species included in the Atlas separately for longline, pole and line, purse seine and other gears fisheries from the historical perspective. The lack of the reported spatial catch data should not necessarily be interpreted as indicative of no catches made. Particularly in the initial and final years of the periods for which the data were provided, the spatial catch data may not be complete.
The annual spatial catch of the longline fishery (red line) was fluctuating around 400 000 tonnes from the early 1960s to present, with a peak of about 533 000 tonnes in 2004. Figure 8 gives the species composition of longline spatial catches. The species that fetch the highest price per kilogram (i.e., Atlantic, Pacific and southern bluefin all combined as blue line) contribute only a small fraction of the total catch. Bigeye tuna (green line), also fetching high prices per kilogram, has recently been contributing the largest fraction of the spatial catches, followed by yellowfin (yellow line) and albacore (white line).
In the early 1970s, the reported annual spatial catch for the pole and line fishery (blue line in figure 7) increased dramatically reaching a maximum of 556 000 tonnes in 1984. The species composition for pole and line spatial catches is shown in Figure 9. Skipjack (red line) contribute mainly to these catches.
The purse seine fishery (green line in figure 7) now produces most spatial catches in terms of weight. These catches were increasing nearly continuously from 1962 to 2009 (the last year for which catch data are complete), when catches of about 3.4 million tonnes was reported. Figure 10 gives the species composition for the purse seine spatial catches. Skipjack (red line) and yellowfin (yellow line) are predominant in the purse seine catches.
The spatial catches of other gears fishery included in the Atlas only represent a small portion of the total catches (grey line in figure 7). Catches of skipjack and yellowfin (red and yellow lines in figure 11) contribute the largest fraction of the spatial catches.
Some catches are unknown or poorly known and they are not accounted for on the maps of the Atlas. Many artisanal and some commercial fisheries (e.g., Japanese pole and line fisheries in the Pacific Ocean prior to 1978) contribute to such catches of poorly known locations. Other spatial catch data were provided only in number of fishes (i.e., Japanese longline catches in the Indian Ocean) and they are also excluded fro the Atlas. The latter catches may represent a significant portion of catches in some regions.
For the Atlantic industrial fisheries, ICCAT combined data by 5° x 5° rectangle and quarter and raised their data to the level of its nominal catches. For most small-scale fisheries in the Atlantic, catches which are not reported by 5° x 5° and quarter resolution are also assigned to specific rectangles. For the Pacific, data received from WCPFC, also such adjustments were made to a significant extent. In particular, for the western and central Pacific Ocean, the adjustments have been done for certain large industrial fleets (e.g., Korean longliners) and for several local fleets of commercial vessels (e.g., New Caledonian longliners). On the other hand, certain fleets, such as the Japanese coastal longline fleet, are not yet included to WCPFC's data.
For the Indian Ocean and the remainder of the Pacific, such adjustments have not been mostly done, not accounting for a significant portion of nominal catches especially for small-scale fisheries in the Indian Ocean. Also for the eastern Pacific, catches from industrial longline from logbooks are not accessible by the public domain and therefore they are not included in the Atlas. In the Western and Central Pacific, catches in 5° x 5° cells where less than 3 vessels operate are not available to the general public. Since 1970, less than 2% of total annual catch for each year has been removed and since 2000, less than 1% of total annual catch for each year has been removed.
Further information on tuna fisheries can be accessed from the Tuna Fisheries
Presentation of data
The display of spatial catches is possible through an Internet based interface form which the user can select each items considered in the data set and the preferred method of presentation.
The first step is to select one or more items under the Species and Gears tabs. Multiple selection of items can be done by simultaneously pressing the CTRL key and the mouse left button.
The second step is to select, under the Time tab, the aggregation method, where options are between presenting spatial average and cumulated catches across years and quarters.
The application is launched by clicking on the “Map it” label.
The resulting map shows the magnitude of catches in each 5º latitude by 5º longitude cell by shading each cell with different colours assigned to certain ranges of catch magnitude. A limited range of colours are used on a single map, so that classes can be easily distinguished.
Once the resulting map is displayed, the user can access a printable version of the map or download the subset of data used for creating the map output. The downloadable file is in Comma Separated Value format.
Collection Method: FAO's the Fisheries Marine and Inland Fisheries Service (FIRF) received spatial catch data for tuna and tuna-like species by: species (including albacore, bigeye tuna, black marlin, blue marlin, northern bluefin tuna, sailfish, skipjack tuna, southern bluefin tuna, striped marlin, swordfish, yellowfin tuna and other tuna and tuna-like species), fishing gear (purse seine, pole and line, longline and other fishing gears), 5° latitude by 5° longitude or smaller rectangle and by year and quarter.
Processing Method: The statistics collated by FAO's Marine and Inland Fisheries Service (FIRF) were integrated into one data set which is provided in the Atlas. In that set, catch data are provided by species, fishing gear, 5° by 5°, year and quarter.
In some cases, the following adjustments were introduced to the individual data sets before combining them into one set, which is shown in the Atlas: