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data substitution on the assessment is unknown, but certainly was another contribution to the increasing distance
between the outlook and the reality.

Another issue is related to the CPUE series used in tuning the VPA. One of the most reliable for the East
Atlantic stock was originally the Japanese longline series because the data are collected with a very accurate
methodology. This series showed a strong decreasing pattern and this was attributed at the beginning to a clear
sign of lower abundance of the stock. During the ICCAT/GFCM meeting held in Genoa (Italy) in 1996, it was
clearly detected that the LL CPUE data for the Japanese fleet operating in the Mediterranean were negatively
affected by the increasing number of fish stolen from the LL by various fishing vessels5. This problem, able to
seriously bias the analysis, was described and agreed, but the data are still used without any correction factor and
those contribute to lowering all the abundance estimates.

Total catch data, after the adoption of the quota system, faced a real disaster: it was possible for several CPs to
revise their catch statistics for the years previous to the adoption of the quota, which were calculated on the 1995
and 1996 catches. Some CPs really tried their best to get the most reliable statistics, recovering data from any
possible source (including sales notes and invoices), Some others apparently revised their statistics with few (if
any) references to specific documents. The reason for that was to try to obtain the highest possible portion of the
quota, and this was the real “gold rush”. Furthermore, the situation was complicated by the request to establish
new allocation criteria, not only considering the historical catches but also the new needs of coastal CPs, even
without any tradition in the bluefin tuna fishery. This new problem was based on the right of each CP to access a
distributed resource, which is justified in principle. The result of this exercise was a further problem in the
system: CPs with a long historical tradition but with weak statistics got quota shares that were insufficient to
cover their real fishing capacity at that time, while others got quota shares that were well above their fishing
capacity. In a very few cases, vessels from the first set of CPs moved to some CPs of the second group. The final
result was that many CPs were suspected of under-reporting their total catch, some of them were officially
identified by the ICCAT Compliance Committee by cross checking the export data with the catch data, WWF
submitted several severe and documented reports on this issue (Mielgo Bregazzi, 2006, 2008, 2009) and the
SCRS tried to reassess the total figure of catch for the East Atlantic bluefin tuna stock by using theoretical
fishing capacity estimates, which were used in the assessment as a part of the uncertainty and to develop various
management scenarios.

SCRS, in all its reports since about 15 years ago, stated very clearly that there was a progressive deterioration “of
the data” and, after the adoption of the quota system, that the data used for the assessment were “considered
unreliable”.

The final result of these and many other wrong or manipulated inputs to the VPA are now evident. The 2008
assessment (Anon. 2009), in its best scenario, reports a SSB of only 71,000 tons and a total biomass ranging
from 1 to 2 million bluefin tuna. These numbers are clearly very under-estimated in comparison to the real
world, because in the same year the total estimated catch was around 61,000 tons. It is also well known that each
single school of very small bluefin tuna (7-8 cm) can account for more than 120,000 individuals, while this
number changes according to the individual size, and there are usually at least many hundreds of these schools in
each geographic area where there is the proper food chain. The very high number of juveniles is also confirmed
by the huge catch rate reported in the past for several small boats illegally fishing for bluefin tuna. Even the
catch of large specimens every year provides important numbers. These data combined show that the current
assessment provides, under the most optimistic scenarios, total biomass and SSB which are clearly
underestimated.

6. The request to move the northern bluefin tuna, Thunnus thynnus (Linnaeus, 1758), under the CITES
Appendix 1

The proposal to include the northern bluefin tuna (the West Atlantic and the East Atlantic stocks) into the
Appendix 1 of the Washington Convention (better known as CITES) was promoted by the Government of
Monaco in July 2009 and subsequently endorsed by various countries, most of them not concerned with the
bluefin tuna fishery.

5 The level of subtraction of bluefin tuna from the Japanese longlines was very high. It was possible to detect about 30 tons of stolen bluefin
tuna in only one harbour in one single year.

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