Where does my data go? Preparation of files for the assessments of IOTC stocks and use of data for the assessments of IOTC species Mauritius, 18-20 March 2014 Compliance Workshop: Collection and reporting of Fisheries data to IOTC Sponsored by BOBLME-IOC- SmartFish-IOTC
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Where does my data go? Preparation of files for the assessments of IOTC stocks and use of data for the assessments of IOTC species Mauritius, 18-20 March.
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Where does my data go?Preparation of files for the assessments of IOTC stocks and use of data for the assessments of
IOTC species
Mauritius, 18-20 March 2014Compliance Workshop: Collection and reporting of Fisheries data to IOTC
• Life history information• Longevity/natural mortality (tagging; otoliths)• Growth (tagging; otoliths)• Maturation (biological samples)
Spatial and seasonal patterns
Routine Data
Collection
Data Collection
through specific projects
(updated regularly)
Building blocks of management advice
Slide from R. Method modified by Joseph E.
Powers
Input files prepared for the assessments
IOTC SECRETARIAT
• Catch [and effort] data by species, time-period (usually quarter), fishery (groups of Flag-Gear combinations depending on the selectivity) and areas (depending on the dynamics of the fleets and species for assessment)
• Number of fish sampled by species, size bin, time-period… (as above)
• Length-weight, growth, and other functions used for each species
• Life history information
FLAG STATES
• Indices of abundance (from as many fleets as possible); estimated using fine-scale operational data (logbooks)
Example of BET input files
Bigeye tuna SS3 Assessment
Species Species code (BET: bigeye tuna)
Fishery Type of fishery: the following fisheries were identified:PSFS Industrial purse seines on free-swimming schoolsPSLS Industrial purse seines on associated schools (FAD)
LL [Deep-]freezing longline fisheries, especially Japan, Korea, Taiwan,China, Seychelles, and EUFL Fresh-tuna longline fisheries, especially Indonesia and Taiwan,ChinaBB All pole-and-line and small seine fisheries (catching small fish)
LINE All fisheries using handlines, and small longlines, including the gillnet and longline combination fishery of Sri LankaOTHER Other fisheries including gillnet, trolling and other minor artisanal gears
Year The year where the catches were made
Quarter The quarter where the catches were made (Jan-Mar(1), Apr-Jun(2), Jul-Sep(3), Oct-Dec(4))
no Total catch estimated (in numbers of fish)mt Total catch estimated (in metric tonnes)noSamp
L010…L308 Number of bigeye tuna sampled by (fork) length class, using 10cm as the first class(lower bound) and 2cm intervalsL010 Number of BET specimens having a fork length between 10cm (inclusive) and 12cm (exclusive)L012 Number of BET specimens having a fork length between 12cm (inclusive) and 14cm (exclusive)And so forth
The catches for fisheries for which catches by quarter were not available were allocated using the proportion that the catches in each quarter made in other years for the same fleet, for other fleets in the same or other years or were assigned proportionally by quarter, depending on the case
Total number of fish sampled: Note that the numbers of fish refer to actual numbers of fish sampled in all fisheries but the PSLS and PSFS fisheries, where they refer to the number of specimens raised to the sampling unit (i.e. number of fish estimated for the sets withing the fish compartment (fish well) sampled)
Steps in the preparation of datasets
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SF aggregated per Species, Fleet, Gear Type, Grid and time interval
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SF data assigned per Species-Fleet-Gear-School Type-Year-Quarter-SF Grid ( EC PS Areas for PS, 10*20 degrees Areas for all
other gears)
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Flow-chart: Estimation of Catch-at-Size Tables and Spatial Catches