Overview

A collection of code lists:

  • characterising elements of core statistical datasets (type of data, data raising, and estimation)
  • classifying types of data sources (dataset-specific)
  • classifying types of data processing (dataset-specific)
  • describing original data coverage

Return back to the list of reference data domains.

Data Origin and Processing

Paragraph 3.(a) of IOTC Res. 15/02 state the following concerning catch-and-effort data: “(…) The data shall be extrapolated to the total national monthly catches for each gear. Documents describing the extrapolation procedures (including raising factors corresponding to the logbook coverage) shall also be submitted routinely”.

In addition, the following is stated in Paragraph 4 (Size Data): “(…) Size sampling shall be run under strict and well described random sampling schemes which are necessary to provide unbiased figures of the sizes taken.” and “(…) Length data by species, including the total number of fish measured, shall be submitted by a 5 grid area by month, by gear and fishing mode (…)”.

Types of Datasets

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  • Version: 1.0.0
  • Last update: 2023-05-12

Reference codes modelling the different type of fishery statistics datasets reported to the IOTC Secretariat (see also: the datasets available to IOTC).

Types of Data

Reference codes for the type of statistics provided through a specific form, and in particular if these are:

  1. preliminary if the statistics were estimated by using some information from the fishery and year concerned, and the data reported are likely to change in the future as more information becomes available; or
  2. final if the statistics were estimated by using the complete set of data from the fishery and year concerned, and the data reported are unlikely to change in the future.

Raisings

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  • Version: 1.0.0
  • Last update: 2023-05-12

Reference codes for the level of raising applied to the data, and in particular if data:

  1. have been raised to represent the total catches and efforts in the year concerned (RT),
  2. have been raised but do not represent the total catches and efforts in the year concerned (PR), or
  3. have not been raised at all (NR)

Estimations

Reference codes indicating if the data estimated for a stratum was actually recorded in the stratum or derived from comparable strata through a substitution scheme.

Sources

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  • Version: 1.0.0
  • Last update: 2023-05-12

The types of datasets that were used to estimate the statistics that are reported to the IOTC and main sources for those datasets.

Sources of Catch and Effort Data

Reference codes for the source of data provided through the catch and effort data forms.

Sources of Discard Data

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  • Version: 1.0.0
  • Last update: 2023-05-12

Reference codes for the source of data provided through the discard data form.

Sources of Data on Fish Aggregating Devices

Reference codes for the source of data provided through the FAD data form.

Sources of Data on Fishing Crafts

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  • Version: 1.0.0
  • Last update: 2023-05-12
  • Forms: 2FC

Reference codes for the sources used to determine the number of fishing craft reported in the fishing craft data form.

Sources of Data on Retained Catches

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  • Version: 1.0.0
  • Last update: 2023-05-12
  • Forms: 1RC

Reference codes for the sources of the data provided through the retained catch data form.

Sources of Data on Size-Frequencies

Reference codes for the sources of the data provided through the size-frequency data form.

Processings

Reference codes for the types of processing applied to raw information to obtain the data provided through a specific form.

Processings of Catch and Effort Data

The most common methods used to estimate retained catches, discards, numbers of fishing crafts, catch-and-effort, and size data from the datasets collected for each fishery.

Processings of Discard Data

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  • Version: 1.0.0
  • Last update: 2023-05-12
  • Forms: 1DI

Reference codes for the processings applied to the data provided through the discard data form.

Processings of Fish Aggregating Device Data

Reference codes for the processings applied to the data provided through the FAD data form.

Processings of Fishing Craft Data

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  • Version: 1.0.0
  • Last update: 2023-05-12
  • Forms: 2FC

Reference codes for the methods used to estimate the number of active fishing crafts.

Processings of Retained Catch Data

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  • Version: 1.0.0
  • Last update: 2023-05-12
  • Forms: 1RC

Reference codes modelling the processing applied to the data provided through the retained catch data form.

Processings of Size-Frequency Data

Reference codes modelling the processing applied to the data provided through the size-frequency data form.

Data Coverage

Coverage’ refers to the proportion that the amount of fish (in number or weight) or fishing effort that is monitored (sampled) makes out of the total estimated in the stratum concerned.

Types of Coverage

The type of metrics used to determine the coverage of each stratum for a given dataset.

Actual coverage values, i.e., the proportion that the total number of fish sampled (or sampled weight) for the species make out of the total number (or weight) of fish caught for that species and fishery concerned, shall be provided as a separate field attached to each stratum.