A Snapshot of the Tropical Tuna Purse Seine Large-Scale Fishing ...

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capacity to store fish. Two such measures are commonly used in the literature: Fish carrying capacity (FCC) and fish hold volume (FHV). Here we conceptualize current capacity in very general terms without distinguishing between different types of current capacity such as that being actually realized ("active" capacity) or that which is "latent". We included data for vessels that are currently authorized to fish, whether they fish or not. 2.1 Sources of information Each of the five tRFMOs (CCSBT, IATTC, ICCAT, IOTC and WCPFC) is required to maintain one or more records (registers) of vessels authorized to fish in their convention areas. In some cases these records are specific to vessels fishing for a particular species and in other cases they are general lists of vessels authorized to fish any species managed by that Commission. There are several known problems with these lists, including: - Individual vessels may be authorized in two or more RFMO areas at the same time; being authorized to fish is not the same as actively fishing. - The information entered in the lists is, for the most part, reported by government agencies of the RFMO members. To the degree that not all agencies have the same ability to monitor and manage their vessels, the information on the lists is of highly variable quality. Furthermore, different countries may use different definitions of vessel attributes such as length and tonnage. - Even though each of the RFMO lists has several mandatory fields, much of the information is incomplete or absent. - The RFMO lists are not necessarily updated in real time. The frequency of updates is not synchronized with the frequency with which vessels change flags, names, etc. For the above reasons, it must be borne in mind that the RFMO records are not 100% accurate at any given point in time. Nevertheless, these lists are improving as the RFMOs exercise greater scrutiny over them, and they are currently the best source of information available for tuna fishing fleets at the global level. The primary sources of information used in this paper were the RFMO vessel records downloaded from their respective Web sites on December 16, 2011. Other sources of information were consulted in order to verify duplicate entries, fill in missing data, or reconcile contradictory information for a given vessel: - The Consolidated List of Authorized Vessels (CLAV) that is put together several times each year by the five tRFMO Secretariats. Putting together this consolidated list involves merging the five lists and using computer algorithms to identify entries that are likely duplicates. The CLAV is hosted at http://tunaorg.org/GlobalTVR.htm. The version created on October 10, 2011 was used. - The Forum Fisheries Agency (FFA) list of vessels "in good standing". Certain vessels operating in the western Pacific Ocean are not required to be on the WCPFC record if they do not fish on the high seas or in more than one EEZ. The 2
list is published at http://www.ffa.int/node/42; the version corresponding to the first half of December 2011 was used. - TURBOBAT, a database of vessels maintained by scientists of the Institut de Recherche pour le Développement (IRD) and the Instituto Español de Oceanografia (IEO). The database focuses primarily on European and associated flag vessels fishing for tropical tunas in the Indian and Atlantic oceans. The database used was updated December 6, 2011. - Consultation with several members of the industry and government agencies as needed. 2.2 Processing The following steps were taken to compile the list of vessels in this document: 1. Retrieve the CCSBT, FFA, IATTC, ICCAT, IOTC and WCPFC lists and select purse seine vessels only. 2. Identify duplicates. This involved sorting by Flag and then by name and manually identifying vessels of the same name or similar name (e.g., "No. 8 XXX" and "XXX No. 8") and the same characteristics such as size or radio call sign. The CLAV was consulted as needed. 3. Fill in missing fields (hold volume, fish carrying capacity, LOA) when data were available from the TURBOBAT file. 4. Set LOA: If several vessel size measurements were available, LOA was set to the largest value. This is because usually either LOA or LBP, or both, are reported in the RFMO lists and LOA>LBP. 5. Set GRT: If several vessel tonnage values were available, GRT was set to the smallest value. This is because usually GRT and GT are recorded in the lists and GRT
Page 1: ISSF Technical Report 2012-01 A Sna
Page 5 and 6: Figure 1. Distribution of purse sei
Page 7 and 8: Figure 4. Relationship between betw
Page 9 and 10: Limiting the list to large-scale ve
Page 11 and 12: fishery, 678 purse seiners. This di
Page 13: Appendix 1. Glossary FCC. Fish Carr

A Snapshot of the Tropical Tuna Purse Seine Large-Scale Fishing ...

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