|
The CCSBT collects a variety of
data types from its members and cooperating non-members, including
total catch, catch and effort data, and catch at size data.
Catch and trade information is also collected through the
Commissions Trade Information Scheme, Japanese import statistics,
and other monitoring programs.
Relevant subsets and summaries of these data are provided below. All figures are subject to change as improved data or estimates
become available. In particular, recent reviews of SBT farming
and market data suggests that southern bluefin tuna catches may have
been substantially under-reported over the past 10-20 years and the
data presented here do not yet include estimates for this unreported
catch. Also, data for the last reported
year of catch (2006) are preliminary and are subject to revision. Any latitudes and longitudes presented in these summaries represent
the north western corner of the relevant grid, which is a 5*5 grid
unless otherwise specified.
Other information on members
and cooperating non-members fishing activities appears in the reports of
the Scientific Committee and the Commission's reports.
| |
Estimated Total Global Catch of Southern Bluefin Tuna |
 |
Estimates of the global SBT catch will be updated on
an annual basis within two months of the Commission's annual meeting
in October of each year.
All data in this section are provided as whole
weights in tonnes. Note: the catch data provided here do not
include estimates of past unreported catches.
Annual catch by flag or gear from 1952 to 2006
inclusive
Catch by ocean, year and flag from 1965 to
2006 inclusive
The SBT catch in this dataset has been subdivided into three
oceans (Indian, Pacific and Atlantic) according to
ocean
definitions (PDF 128kb) defined by the
CCSBT Secretariat. Due to the absence of requisite data, it
has been assumed that all Indonesian catches, miscellaneous catches,
pre-2000 Philippine SBT catches, and pre-1981 Taiwanese catches were
from the Indian Ocean.
It should also be noted that the data for individual
flag states and fishing entities shown here may differ to data that those flag
states and fishing entities have provided
separately to other organisations. This is in part due to the data
manipulations conducted by the CCSBT in producing this dataset (a
variety of data sources were used, requiring a range of correction
and raising techniques) and in part due to differences in the data
provided by individual flag states and fishing entities to the CCSBT and to other organisations.
In particular, the post 1994 SBT data provided by Japan to the CCSBT
differs from the post 1994 SBT data that Japan provides to other
regional fishery management organisations. The data that Japan
provides to CCSBT takes advantage of a Real Time Monitoring Program
for SBT to collect daily catch and effort reports from SBT targeting
fishing vessels and this is considered to minimise the time lag in
availability of the Japanese SBT log book data.
Catch by year, month, gear, ocean and 5 degree
grid from 1965 to 2006 inclusive
The comments made regarding the above "catch by ocean, year and flag"
data also apply to this more highly stratified data.
In addition, all Indonesian, miscellaneous, and pre-2000 Philippine SBT
catches have been assumed to have been taken by longlining.
Information on the month, latitude and longitude of the catch are
occasionally missing within these data. Finally, a small proportion of cells
have weights that are less than the weight of a single fish. This is a consequence of some of the
catch estimation procedures that were used.
| |
Catch and Effort Data |
|
Aggregated catch and effort data from CCSBT members
for the commercial longline and surface (purse seine, pole and line
only)
fisheries for SBT are available below. It should be noted that the data for
individual flag states and fishing entities available here may differ to data that
they provided to other organisations. For further details see
the related comment in the sub section "Catch by ocean, year
and flag from 1965 to ..." above.
It should also be noted that the catch and effort data
provided here do not cover the full time-series of SBT fishing by
each flag state and fishing entity, nor
do they contain the entire SBT catch for any year. In
addition, prior to 1996, the SBT catch reported here for the Fishing
Entity of Taiwan has been estimated from mixed bluefin tuna (species
not reported separately) data. The reason for incomplete time series is
because the catch and effort data is compiled from vessel logbooks
or similar detailed records that may not have been collected
throughout a nations fishing history. Similarly, in some years,
there may not be complete coverage of a particular fleet by catch
and effort data collection systems. For a more
complete history of SBT catches or for a full coverage of the catch,
please refer to the previous section on the "Total Global Catch of Southern
Bluefin Tuna".
With the exception of South Korea, the data provided
here are not restricted to fishing that targeted SBT. Instead,
the data represents all longline, purse seine and pole & line
fishing in which catches of SBT were feasible. This includes
fishing that targeted SBT, fishing that targeted other tuna or tuna
like species, and/or fishing conducted in strata
(year/month/area) where SBT were also taken. As a
consequence, there are many fishing records with no SBT catch.
Note: the extent to which fishing effort associated with past
unreported catches has been reported is currently unknown.
This causes difficulties for a meaningful interpretation of catch
per unit effort trends from these data.
Longline Fishery (to December 2006)
The longline catch and effort data available here
for download contains year, month, country code, target species (New
Zealand, South Korean and South African catches only), CCSBT statistical area, latitude
and longitude (by 5° square where available), number of hooks and
number of SBT retained. Within this dataset, there are
occasional missing data (empty cells) for location, number of hooks and number of SBT retained.
Surface Fishery (to December 2006)
The surface fishery catch and effort data available
here for download contains year, month, country code, gear code, CCSBT statistical area,
latitude and longitude (by 1° square where available), number of
search hours, and weight of SBT retained. Within this dataset,
there are occasional missing data (empty cells) for location and number of search
hours. It should also be noted that the weight of SBT retained
in these data are usually only approximate visual estimates of the
weights.
| |
Catch at Size Data |
|
SBT size frequency data for commercial
fishing operations, raised to the total reported SBT catch of the relevant
flag state or fishing entity, are available below. The data contains: year, month,
country code, gear code, CCSBT statistical area, other area
(Australian catches only), latitude and longitude, length class
(upper end of class in cm), length class precision (in cm) and the
adjusted (raised) frequency. At present, raised size frequency
data at this resolution are only available for Australia (1952 to 2006 - but prior
to 2002 this is not separated by gear type and does not include
latitude and longitude), Japan (1965 to 2006), New Zealand (1989 to
2006 - but without spatial and temporal stratification in 1989) and the Fishing Entity
of Taiwan (2002 to
2006). Where available, the latitude and longitude is
presented as 5° squares for longlining and unclassified gear types,
and 1° squares for other gear types.
| |
Trade Information Scheme (TIS) Data |
|
Subsets of the
Annex 2 and Annex 2a reports of the
CCSBT Trade Information Scheme
(PDF
642Kb)
will be updated on an annual basis and made available for download
below.
Subset of Annex 2 Report (January 2001 to
December 2006 inclusive)
Provides information on the net weight and source of southern
bluefin tuna (SBT) imports by CCSBT members and cooperating
non-members. The report contains: export period (6 month
groups), import country/fishing entity, flag state/fishing entity,
harvest year (for non-farmed SBT), gear code and net weight.
Subset of Annex 2a Report (July 2002 to
December
2006
inclusive)
Provides information on both imports and exports of southern bluefin tuna by CCSBT members and cooperating non-members.
This report also provides a "best" net weight estimate of SBT trade
through a reconciliation of import and export TIS information.
The report contains: export period (6 month groups), import
country/fishing entity, flag state/fishing entity, net weight from
imported TIS documents, net weight from the exporter's TIS records,
and the overall estimated net weight from reconciling the import and
export TIS records.
|
