Main elements
- Fisheries
- IOTC main areas
- Species group: marine turtles, seabirds, mobulid rays, cetaceans, and whale sharks
Guidelines for the reporting of fisheries statistics to the IOTC
Author: IOTC Secretariat
General purposes
Effective collection and reporting of fisheries data are essential for conserving and sustainably managing tuna and tuna-like species in the Indian Ocean. The Indian Ocean Tuna Commission (IOTC) has identified several datasets critical for monitoring tuna and tuna-like fisheries and analysing the status and trends of both the populations and the marine ecosystems that support them. These datasets must be reported by the IOTC Contracting Parties and Cooperating Non-Contracting Parties (CPCs) as part of the IOTC Agreement but they are also requested from any other Parties that fish in the IOTC Area of Competence for species managed by the IOTC.
Since its establishment in 1996, the IOTC has developed and implemented several Conservation and Management Measures (CMMs) which include specific provisions on the nature and characteristics of the data that must be collected and reported to the IOTC Secretariat. It is the responsibility of each country to establish and enforce data recording and reporting systems that meet the criteria set by the IOTC through its CMMs and the Secretariat oversees the collation and curation of the different datasets that support the IOTC scientific process.
The overarching objective of the Data Reporting Guidelines (DRGs) is to provide a set of rules and best practices to the staff responsible for the collection and reporting of fisheries and biological data to the IOTC Secretariat according to the CMMs in place. The DRGs aim to:
- Introduce the users to the IOTC terminology (section Terminology)
- Provide the framework and standards for reporting the elements of the data along with the metadata information required for their storage and management (section Metadata)
- Describe the contents of each dataset as included in the mandatory IOTC reporting forms (section Datasets),
- Present the IOTC data quality control procedure and detail the checks to be performed on the metadata and data prior to any submission (section Quality control procedure)
- Explain the main features of the submission process, including details on the data submission platform, reporting timeline, structure of the files to be reported, and procedure for revising historical submissions (section Data submission procedure).
These guidelines do not include the reporting requirements related to the Regional Observer Scheme (ROS; 22/04) as well as to the monitoring of authorised and active fishing vessels (Res. 10/08 and Res. 19/04), landings and transhipments of fish products in fishing ports (Res. 16/11), and transhipments at sea (Res. 23/05) which are managed by the compliance section of the Secretariat.
Terminology
While many definitions, classifications, and standards within the IOTC are consistent with those of the Coordinating Working Party on Fishery Statistics (CWP), the Commission also employs several technical terms and definitions unique to its operations, which are crucial for accurately reporting fisheries data to the Secretariat.
Area of competence
The IOTC area of competence is defined in the article II of the IOTC Agreement and corresponds to “the Indian Ocean and adjacent seas, north of the Antarctic Convergence, insofar as it is necessary to cover such seas for the purpose of conserving and managing stocks that migrate into or out of the Indian Ocean”. For statistical purposes, the IOTC area of competence is split between two main areas: the Western Indian Ocean and Eastern Indian Ocean (Fig. 1).
Figure 1: Main areas of the IOTC area of competence
Species of interest
The 16 species and stocks managed by the IOTC – hereinafter referred as the IOTC species and IOTC stocks – are defined in the article III of the IOTC Agreement. It is important to note that the distribution of the stock of southern bluefin tuna (Thunnus maccoyii) extends over the Atlantic, Indian, and Pacific Oceans, and its actual management is under the responsibility of the Commission for the Conservation of Southern Bluefin Tuna (CCSBT).
In addition, the IOTC identified a list of species, mostly composed of commonly caught elasmobranch species, for which data reporting obligations apply as for the IOTC species. The Annex 2 of Res. 15/01 provides this list of species and species groups by gear group and was further complemented for all manta rays through Res. 19/03.
Res. 15/01 further includes groups of Endangered, Threatened, and Protected (ETP) species that may interact with IOTC fisheries and for which data collection and reporting has been defined through specific CMMs: marine turtles (Res. 12/04), whale sharks (Rhincodon typus) (Res. 13/05), cetaceans (Res. 23/06), and seabirds (Res. 23/07).
The most commonly caught elasmobranch and ETP species were designated as species of special interest by the Scientific Committee at its 21st session in 2018 to enhance the voluntary collection of information on post-release mortality of discards (IOTC 2021).
Finally, and while optional, the reporting of statistics for all other bycatch species is encouraged to monitor the ecosystem effects of fishing, especially when the catches of these species represent a significant proportion of the total catches of the fishery concerned.
Fishing fleet
A fishing fleet is a group of fishing vessels that may operate in the IOTC area of competence and whose fishing operations and catches of tuna and tuna-like species are under the responsibility of a political entity or sub-entity recognized by the IOTC. The fishing fleet is derived from the combination of the flag state and reporting entity (see section on Reporting metadata). In most cases, the fishing fleet corresponds to the flag state but some differences stem from: (i) when the CPC is composed of multiple entities (i.e., European Union (EUR) and China (CHN)), (ii) the cases of France Overseas Territories (FRAT) and British Indian Overseas Territories (GBRT), and (iii) the existence of estimates of unreported catches not included elsewhere (e.g., NEI.PS) that need to be accounted for in the IOTC process.
Fishery categories
The three main IOTC fishery categories are defined according to the main gear used by the vessel and their recording in the IOTC Record of Authorised Vessels (RAV): (i) longline fisheries, (ii) surface fisheries, and (iii) coastal fisheries, also called artisanal fisheries (see footnote 1 of IOTC Res. 15/02). The IOTC data reporting obligations defined through the CMMs vary according to the fishery categories.
Fisheries
The IOTC fisheries are derived from the combination of several factors: (i) the fishery purpose, (ii) the area of operation, (iii) the vessel size range, (iv) the gear group, (v) the gear, (vi) the gear configuration, (vii) the fishing mode in the case of purse seines, hooks and lines, and pole-and-lines, and (viii) the target species. The IOTC fishery identification wizard has been designed to guide the adoption of the new fishery classification by providing an interactive tool which generates the code and definition of the fishery based on the aforementioned factors.
Reporting metadata
General information
Some mandatory (M) and optional (O) descriptive metadata elements have been identified to provide key information related to the submission and management of the data.
| Element | Requirement | Description | Format | Example |
|---|---|---|---|---|
| Liaison officer full name | M | Name of the liaison officer in charge of the compilation of the data | Plain text | John Doe |
| Liaison officer email | M | Email address of the liaison officer in charge of the compilation of the data | Valid email address | John.Doe@fao.org |
| Organisation name | M | Name of the organisation in charge of the compilation of the data | Plain text | National Institute of Fisheries |
| Organisation email | O | Email address of the organisation in charge of the compilation of the data | Valid email address | nif@gov.sc |
| Finalisation date | M | Date of finalisation of the dataset | ISO 8601 | 1996-03-27 |
| Submission date | M | Date of submission of the dataset | ISO 8601 | 1997-03-21 |
Data characteristics
General information is required to describe the primary characteristics of the data reported to the Secretariat, which are consistent across all datasets.
| Element | Requirement | Description | Input value |
|---|---|---|---|
| Reporting year | M | Gregorian calendar year of the fishing activities reported through the dataset | Integer, e.g., 1997 |
| Reporting entity | M | Entity reporting the dataset to the IOTC Secretariat | Code from Entities |
| Flag state | M | Country registration of the fishery vessels | Code from Countries |
| Original data type | M | Preliminary/final status of the data | Code from Types of data |
Datasets
Species presence in the catch
Description
Matrix of presence of species in the retained catches and discards of each fishing fleet by gear group and broad fishery category.
Conservation and Management Measures
Contents
Matrix table with species in rows and gear groups in columns. For each species/gear combination, the cell must be filled with either a value of one (1) in case of positive catch or a value of zero (0) in case of absence of catch (i.e., no landing and no discard). Species include IOTC species, mobulid rays, common sharks, and other bycatch species. All gear groups (hooks and lines, pole-and-lines, longlines, purse seines, gillnets, and other gears) are included and further broken down by broad fishery category, i.e., coastal and longline or purse seine.
Reporting metadata
Data dimensions
Interactions with Endangered, Threatened and Protected species
Description
Annual estimates of the numbers of interactions of longline fisheries and surface fisheries with endangered, threatened, and protected species by fishing fleet, fishery, IOTC main area, and species group.
Conservation and Management Measures
Contents
Number of interactions with marine turtles, seabirds, mobulid rays, cetaceans, and whale sharks, with information on national legislation in place in the case of cetaceans and whale sharks. For each stratum, the data coverage – i.e., the percentage (%) of occurrences of interactions sampled – derived from the coverage type must be reported to assess the representativeness and quality of the estimates.
Reporting metadata
Data dimensions
Original data
Source coverage
Amount of fish caught and retained
Description
Total annual estimates of the amount of fish caught and retained by fishing fleet, fishery, IOTC main area, retain reason, and species.
Conservation and Management Measures
- Res. 15/01 (Annex II) – On the recording of catch and effort data by fishing vessels in the IOTC area of competence
- Res. 15/02 (para. 2) – On mandatory statistical reporting requirements for IOTC Contracting Parties and Cooperating Non-Contracting Parties (CPCs)
- Res. 17/05 (para. 6) – On the conservation of sharks caught in association with fisheries managed by IOTC
- Res. 18/02 (para. 3) – On management measures for the conservation of blue shark caught in association with IOTC fisheries
- Res. 18/05 (para. 8) – On management measures for the conservation of the billfishes: striped marlin, black marlin, blue marlin and Indo-Pacific sailfish
Retention bans in longline and surface fisheries
- Res. 12/09 – On the conservation of thresher sharks (family Alopiidae) caught in association with fisheries in the IOTC agreement area
- Res. 13/06 – On a scientific and management framework on the conservation of sharks in association with IOTC managed fisheries – Oceanic whitetip shark
- Res. 19/03 – On the conservation of mobulid species caught in association with fisheries in the IOTC area of competence
Contents
Estimates of retained catches in live weight equivalent (metric tonnes; t) for the IOTC species, common sharks, and other bycatch species. Reporting of quarterly estimates is voluntary and recommended to assess seasonality of the retained catches. For each stratum, the data coverage – i.e., the percentage (%) of amount of fish sampled – derived from the coverage type must be reported to assess the representativeness and quality of the estimates.
Reporting metadata
Data dimensions
Main elements
Original data
Source coverage
Amount of discards
Description
Total annual estimates of the amount of fish caught and discarded by fishing fleet, fishery, IOTC main area, species, and condition.
Conservation and Management Measures
- Res. 15/01 (Annex II) – On the recording of catch and effort data by fishing vessels in the IOTC area of competence
- Res. 15/02 (paras. 2-3) – On mandatory statistical reporting requirements for IOTC Contracting Parties and Cooperating Non-Contracting Parties (CPCs)
- Res. 12/09 (paras. 3-5, 8) – On the conservation of thresher sharks (family Alopiidae) caught in association with fisheries in the IOTC agreement area
- Res. 13/06 (paras. 4-5, 8) – On a scientific and management framework on the conservation of sharks in association with IOTC managed fisheries
- Res. 17/05 (para. 6) – On the conservation of sharks caught in association with fisheries managed by IOTC
- Res. 18/02 (para. 3) – On management measures for the conservation of blue shark caught in association with IOTC fisheries
- Res. 19/03 (para. 8) – On the conservation of mobulid species caught in association with fisheries in the IOTC area of competence
Contents
Estimates of discards in numbers or live weight equivalent for the IOTC species, mobulid rays, whale sharks, cetaceans, common sharks, and other bycatch species. Reporting of quarterly estimates is voluntary and recommended to assess the seasonality of the discards. For each stratum, the data coverage – i.e., the percentage (%) of amount of fish sampled – derived from the coverage type must be reported to assess the representativeness and quality of the estimates.
Reporting metadata
Data dimensions
Main elements
Original data
Source coverage
Geo-referenced catches and efforts
Description
Estimates of species-specific catches and efforts by fishing fleet, fishery, and space and time strata, including the effort exerted by the support vessels assisting the purse seiners.
Conservation and Management Measures
- Res. 15/01 (Annexes I-III) – On the recording of catch and effort data by fishing vessels in the IOTC area of competence
- Res. 15/02 (para. 4) – On mandatory statistical reporting requirements for IOTC Contracting Parties and Cooperating Non-Contracting Parties (CPCs)
- Res. 17/05 (para. 6) – On the conservation of sharks caught in association with fisheries managed by IOTC
- Res. 18/02 (paras 2-3) – On management measures for the conservation of blue shark caught in association with IOTC fisheries
- Res. 18/05 (para. 8) – On management measures for the conservation of the billfishes: striped marlin, black marlin, blue marlin and Indo-Pacific sailfish
Retention bans in longline and surface fisheries
- Res. 12/09 – On the conservation of thresher sharks (family Alopiidae) caught in association with fisheries in the IOTC agreement area
- Res. 13/06 – On a scientific and management framework on the conservation of sharks in association with IOTC managed fisheries – Oceanic whitetip shark
- Res. 19/03 – On the conservation of mobulid species caught in association with fisheries in the IOTC area of competence
Contents
- Estimates of efforts expressed in units consistent with the recording requirements established in Res. 15/01 and complemented by numbers of fishing operations for longline fisheries and surface fisheries (IOTC-2022-SC25-R). For coastal fisheries, it is recommended that effort data be submitted in the same units as those prescribed for longline fisheries and surface fisheries characterised by the same fishing gear.
| Gear group | Primary effort | Secondary effort |
|---|---|---|
| Gillnets (GI) | Number of fishing days | Number of fishing operations |
| Hooks and lines (HL) | Number of fishing days | Number of fishing operations |
| Longlines (LL) | Number of hooks deployed | Number of fishing operations |
| Other gears (OT) | Number of days at sea | Number of active gears/fishing operations |
| Pole-and-lines (PL) | Number of fishing days | Number of fishing operations |
| Purse seines (PS) | Number of fishing hours | Number of fishing operations |
From a general perspective, using trips as a unit of effort is not recommended because trip duration can vary widely due to factors such as vessel size, fishing success, and technical considerations (e.g., fuel availability).
Additional units may be considered to refine and standardise the estimation of nominal fishing effort:
In gillnet fisheries, the surface area of the nets deployed may better reflect effort intensity by accounting for differences in net length and height;
In hooks and line fisheries, the number of hooks may be used as required for longline fisheries;
In pole-and-line fisheries, the number of day-poles used may help account for differences in the number of fishers onboard the vessels;
In purse seine fisheries, the numbers of successful and null fishing operations, searching time, and surface area explored may complement the information provided by fishing time and the total number of fishing sets.
- Estimates of catches for the IOTC species, common sharks, and other bycatch species. Extrapolated to national monthly catch totals is mandatory (M) for longline fisheries and surface fisheries and optional (O) for coastal fisheries.
For each stratum, the data coverage – i.e., the percentage (%) of catch/effort sampled – derived from the coverage type must be reported to assess the representativeness and quality of the estimates. The spatial and temporal resolutions, catch units, and level of extrapolation vary according to the fishery category.
| Category | Temporal resolution | Spatial resolution | Catch unit | Extrapolation |
|---|---|---|---|---|
| Surface fisheries | Month | 1° grid area | Live weight equivalent | M |
| Longline fisheries | Month or finer for the SC | 5° grid area or finer for the SC | Numbers or live weight equivalent | M |
| Coastal fisheries | Year or finer | Irregular areas | Numbers or live weight equivalent | O |
Documentation describing the extrapolation procedures (including raising factors for logbook coverage) is also required and must be routinely submitted (Res. 15/02; para. 4). A template for reporting information on sampling procedures is available in the document IOTC-2021-WPDCS17-27.
Reporting metadata
Data dimensions
Catch main elements
Effort main elements
Original data
Source coverage
Geo-referenced size frequencies
Description
Monthly estimates of size-frequencies of the catch retained and discarded by fishing fleet, fishery, grid area of 5° longitude and latitude, species, and sex for IOTC species, common sharks, and other bycatch species.
Conservation and Management Measures
- Res. 15/01 (Annex II) – On the recording of catch and effort data by fishing vessels in the IOTC area of competence
- Res. 15/02 (para. 5) – On mandatory statistical reporting requirements for IOTC Contracting Parties and Cooperating Non-Contracting Parties (CPCs)
- Res. 17/05 (para. 6) – On the conservation of sharks caught in association with fisheries managed by IOTC
- Res. 18/02 (para. 3) – On management measures for the conservation of blue shark caught in association with IOTC fisheries
- Res. 18/05 (para. 8) – On management measures for the conservation of the billfishes: striped marlin, black marlin, blue marlin and Indo-Pacific sailfish
Reporting metadata
Contents
Size frequencies correspond to the numbers of individuals in a catch or catch sample within each size interval (UN ESCWA). Straight length measurements made using a calliper or measuring board are recommended over fish weights and vary according to fish groups: (i) lower-jaw fork length for billfish, (ii) upper-jaw fork length for tunas, mackerels, sharks, and all other bycatch fish species with forked or lunate tails, (iii) standard length for bycatch fish species with rounded or truncate tails, and (iv) disc width for rays. The Secretariat further recommends the use of length intervals for the IOTC species and most commonly caught sharks, along with maximum length intervals and ranges of valid values, which are used to filter and consolidate the size-frequency datasets made available to support the IOTC process (see Recommended measurements).
Size-frequency data must be collected for the 16 IOTC species and the most commonly caught elasmobranch species listed in IOTC Res. 15/01 for taxa identified at species level.
Size data can be collected either at sea or on land and must be linked to the spatial origin of the catch. Data should be reported following a spatial resolution of 5° grid areas or finer when required by the Scientific Committee. For longline fisheries, size-frequency data may be reported as part of the Regional Observer Scheme, where such fleets have at least 5% observer coverage of all fishing operations Res. 15/02; para. 5.
Sampling coverage should be set at a minimum of one (1) fish measured by tonne caught, by fishery and species, with samples being representative of all the periods and areas fished. For each stratum, data coverage – i.e., the percentage (%) of catch/effort sampled – derived from the coverage type must be reported to assess the representativeness and quality of the estimates. Additionally, raised estimates of the size samples must be reported to the Secretariat to account for any bias resulting from unrepresentative sampling and the spatio-temporal variability of fishing operations. Documents detailingthe sampling and raising procedures must be provided for each fishery and species.
Data dimensions
Main stratum
- Month
- Grids
- Species
- Sexes
- Types of fate
- Fates
Original data
Source coverage
Measurement
AFAD-related activities
Description
Daily activities conducted around AFADs, including catches retained and discarded.
Conservation and Management Measures
- Res. 23/01 (para. 11 and Annex II) – On the management of anchored fish aggregating devices (AFADs)
Contents
Geographic position and description of each fishing activity conducted around each AFAD along with estimates of retained catches and discards in numbers or live weight equivalent for the IOTC species, common sharks, and other bycatch species.
Reporting metadata
Data dimensions
Activity main stratum
- Month
- Day of month
- Latitude (in decimal degrees)
- Longitude (in decimal degrees)
- Fisheries
- AFOB types
- AFOB activity types
Catch main stratum
- Month
- Day of month
- Latitude (in decimal degrees)
- Longitude (in decimal degrees)
- Fisheries
- Species
- Types of fate
- Catch units
Source coverage
DFOB-related activities
Description
Operational activities conducted by purse seine and support vessels on drifting floating objects (DFOBs) and buoys.
Conservation and Management Measures
Contents
When present, information on buoy identifier, knowledge of the buoy position, and type of activity conducted on the buoy. For each DFOB, information on materials (i.e., presence of plastic or metal), dimensions (i.e., length, width, and height), and presence of mesh with value of mesh size for both the surface (i.e., raft) and subsurface (i.e., tail) components. Finally, species-specific estimates of catches retained and discarded in numbers or live weight equivalent for the IOTC species, common sharks, and other bycatch species.
Reporting metadata
Data dimensions
Buoy and DFOB main stratum
- Vessel IOTC number
- Vessel name
- Month
- Day of month
- UTC time
- Latitude (in decimal degrees)
- Longitude (in decimal degrees)
Catch main stratum
- Vessel IOTC number
- Vessel name
- Month
- Day of month
- UTC time
- Latitude (in decimal degrees)
- Longitude (in decimal degrees)
- Species
- Types of fate
- Catch units
Daily buoy positions
Description
Daily positions of operational buoys equipping DFOBs in large-scale purse seine fisheries.
Conservation and Management Measures
- Res. 19/02 (para. 24) – Procedures on a fish aggregating devices (FADS) management plan
Contents
Single daily buoy position (latitude and longitude in decimal degrees) for each of the buoys monitored by each purse seine vessel. Each buoy is identified by its unique identifier which is a concatenation of the acronym of the buoy commercial model (e.g., ISD+, M3+, T8E) followed by 5-9 digits depending on the buoy model.
Reporting metadata
Data dimensions
- Month
- Day of month
- Vessel IOTC number
- Vessel name
Fishing craft statistics
Description
Annual number of active fishing vessels by gear, boat type, size class, and fish preservation method.
Conservation and Management Measures
- UNFSA – Article 4 of the Annex I of the United Nations Fish Stocks Agreement
Contents
Estimates of the numbers of fishery vessels active during the year, stratified by boat type, mechanisation type, fish preservation method, and refrigeration storage system. For each stratum, the data coverage – i.e., the percentage (%) of catch/effort sampled – derived from the coverage type must be reported to assess the representativeness and quality of the estimates.
Reporting metadata
Data dimensions
Main elements
Original data
Source coverage
Fish prices
Description
Monthly prices of fish products for tuna and tuna-like species under IOTC mandate.
Conservation and Management Measures
- IOTC Agreement (paras. 1 and 2d) – Article V. Objectives, functions and responsibilities of the Commission
Contents
Monthly average prices of fish per type of fish product – i.e., processing type, by weight category, and market.
currency,
Reporting metadata
Data dimensions
Main elements
- Month
- Currency
- Destination
- Market
- IOTC Species
- Fish processing types
- Fish preservation methods
- Weight class (lo)
- Weight class (hi)
Quality control procedure
Metadata and data standards
Evaluating the adherence of data submissions to the formats and standards set by the IOTC is essential to uphold the consistency and quality of the data managed by the Secretariat. It is the responsibility of the CPCs and other data providers to ensure the completeness of all metadata and data fields provided to the Secretariat as well as to use the IOTC codelists that build on several international standards and are available from the IOTC data reference catalogue.
The IOTC data reference catalogue is composed of five reference data domains:
The administrative and geospatial domain which include codelists for vessel flags, data reporting countries, fishing fleets, CPCs, and several spatial layers used to report information on fishing grounds;
The fisheries and fishing technologies domain which include several codelists used to describe the IOTC fisheries, vessels, gears and configurations, as well as fishing devices (e.g., floating objects) and materials;
The biological and morphometric domain which includes the IOTC species codelist mostly built on the ASFIS list of species for fishery statistics purposes as well as some code lists used to report information on sampling methods and morphometric measurements;
The data and metadata domain which regroups the codelists used to characterise the elements of the datasets, the data sources, types of processings that can be applied, and coverage types;
The legacy and external references domain which includes some historical codelists of the IOTC and some international reference codes from FAO, CWP, FIRMS, IUCN, and UN.
The information in the IOTC data reference catalogue is continuously updated, meaning that new values are added to the codelists, and old values are removed. If you have any questions or requests regarding the reference tables, you should contact the data section of the Secretariat by emailing IOTC-Statistics@fao.org.
Data submission validation
Some dataset-specific validators have been designed to assess the quality of the data contained in the reporting forms.
Each form must be uploaded to the correspondent validator link when completed
The tool will provide an overview of the analysis carried out on the content
The output of the validation process includes a main box message with flaps of validation messages, ranging from summary information messages to increasing levels of identified issues messages provided in additional flaps. A validation-coloured summary box (left bottom), related with the level of issues message is also provided indicating if the form could be successfully processed or need further revision before to be submitted to the IOTC
When a form is fully filled, and all the mandatory data were included according to the IOTC standard an INFO message will be provided including a summary of the processed information and a validation summary message indicating that the form provided can be successfully processed and submitted to the IOTC.
Data submission procedure
e-MARIS platform
The e-MARIS platform serves as the primary access point for reporting fisheries statistical data to the IOTC Secretariat. The document e-MARIS Quick Start series for CPCs offers guidelines and technical details on connecting to the platform, monitoring IOTC requirements, and submitting the required information. For fishery statistics, all datasets must be submitted according to Requirement 5.0. Additionally, information in the relevant tables and/or sections related to specific datasets must be provided, depending on the fishery category.
Data submission cycle
Res. 15/02 (para. 7) explicitly establishes the requirements for timely annual reporting of the core IOTC datasets, i.e., species presence in the catch, annual amounts of catches retained or discarded at sea, and monthly geo-referenced catches, efforts, and size frequencies:
a. Longline fleets operating in the high seas shall provide provisional data for the previous year no later than 30 June. Final data shall be submitted no later than 30 December;
b. All other fleets (including supply vessels) shall submit their final data for the previous year no later than 30 June;
c. In case where the final statistics cannot be submitted by that date, at least preliminary statistics should be provided.
Res. 19/02 (para. 22) and Res. 23/01 (para. 11) follow the same deadline requirements for DFOB and AFAD-related activities, respectively, while a specific timeline of submission applies to:
The daily buoy position data that must be reported on a monthly basis, at least 60 days, but no longer than 90 days from the end of the month of buoy activities (Res. 19/02; para. 24).
The details of the new AFADs deployed within the EEZ of the CPCs that must be reported within 21 days of deployment of the AFADs (Res. 23/01; para. 8).
Semantics
The data reporting forms are designed to facilitate the submission of comprehensive datasets. Except for the forms 3BU, which contain data on daily buoy positions and are expected to be submitted monthly, the Secretariat anticipates receiving for each fishing fleet the following with each annual submission:
- One single form 1DR to report data on species presence in the catch for all gear groups
- One single form 1IN to report data on interactions with ETP species for all fisheries
- One single form 1RC to report data on the amount of fish caught and retained for all fisheries
- One single form 1DI to report data on the amount of discards for all fisheries
- One single form 3CE to report data on geo-referenced catches and efforts for all fisheries
- One single form 4SF to report data on geo-referenced size frequencies for all fisheries and species
- One single form 3AA to report data on AFAD-related activities for all fisheries
- One single form 3DA to report data on dFOB-related activities for all vessels
- One single form 2FC to voluntarily report data on fishing craft statistics for all fisheries.
Data revisions
If it is not possible to submit the final statistics by the specified deadline (see section Data submission cycle)), then at least preliminary statistics should be provided. Data revisions can be performed at any time by re-submitting updated IOTC forms through e-Maris. To facilitate tracking changes, certain versions of the forms have been designed to allow submission of only the updated components of the dataset:
- Form 3CE-update for a given fishery;
- Form 4SF-update for a given fishery and species;
- Form 3AA-update for a given fishery;
- Form 3DA-update for a given vessel.
If revisions to historical data are made beyond a delay of two years, they must be formally reported and properly justified. These reports should be submitted using forms provided by the IOTC Secretariat and will be reviewed by the IOTC Scientific Committee. The committee will then advise the IOTC Secretariat on whether the revisions can be accepted for scientific use.
List of acronyms
| AFAD | Anchored Fish Aggregating Device |
| CC | IOTC Compliance Committee |
| CMM | Conservation and Management Measure |
| CPC | IOTC Contracting Parties and Cooperating Non-Contracting Parties |
| CWP | Coordinating Working Party on fishery statistics |
| DFAD | Drifting Fish Aggregating Device |
| EC | European Commission |
| EEZ | Exclusive Economic Zone |
| EMS | Electronic Monitoring Systems |
| ETP | Endangered, Threatened and Protected species |
| EU | European Union |
| FAD | Fish Aggregating Device |
| FOB | Floating object |
| GT | Gross Tonnage |
| IOTC | Indian Ocean Tuna Commission |
| IUU | Illegal, Unreported or Unregulated |
| NGO | Non-governmental organisation |
| LOA | Length overall |
| RAV | IOTC Record of Authorised Vessels |
| REMP | Regional Electronic Monitoring Program |
| RFMO | Regional Fisheries Management Organisation |
| ROS | IOTC Regional Observer Scheme |
| SC | IOTC Scientific Committee |
| UK | United Kingdom of Great Britain and Northern Ireland |
| UN | United Nations |
| WP | IOTC Working Party |
Glossary
A
Anchored Fish Aggregating Device
A fish aggregating device tethered to the bottom of the ocean, usually consisting of a buoy, and anchored to the bottom of the ocean (Res. 23/01).
Artisanal fishery
Traditional fishery that involves fishing households (as opposed to commercial companies), using relatively small amounts of capital and energy, relatively small fishing vessels (if any), making short fishing trips close to shore, mainly for local consumption. In practice, definition varies between countries, e.g., from gleaning or a one-man canoe in poor developing countries, to more than 20 m trawlers, seiners, or longliners in developed ones. Artisanal fisheries can be subsistence or commercial fisheries, providing for local consumption or export. They are sometimes referred to as small-scale fisheries (FAO 2005).
Artisanal fishery (IOTC)
Fishery composed of fishing vessels of less than 24 m length overall that exclusively operate in the exclusive economic zone of their flag state, i.e., not recorded in the IOTC Record of Authorised Vessels. Synonym to coastal fisheries (Res. 15/02).
Artisanal fishing vessel (IOTC)
Fishing vessel less than 24 m in length overall operating inside the exclusive economic zone of a flag State and catching tuna or tuna-like species in the IOTC area of competence.
Associated school
The fish school is associated with a topographic structure (e.g., seamount), an anchored or a drifting floating object, including man-made rafts such as fish aggregating devices and live animals in motion (e.g., whale sharks, cetaceans).
B
Bycatch
Discarded catch plus incidental catch (Alverson et al. 1994).
Bycatch species (IOTC)
All species, other than the 16 species listed in Annex B of the IOTC Agreement, caught or interacted with by fisheries for tuna and tuna-like species in the IOTC area of competence. A bycatch species includes those non-IOTC species which are (a) retained (byproduct), (b) incidentally taken in a fishery and returned to the sea (discarded); or (c) incidentally affected by interacting with fishing equipment in the fishery, but not taken.
Byproduct
A species taken incidentally in a fishery while fishing for the target species that has some commercial value and is retained for sale.
C
Coastal fishery (IOTC)
Fishery composed of fishing vessels of less than 24 m length overall that exclusively operate in the exclusive economic zone of their flag state, i.e., not recorded in the IOTC Record of Authorised Vessels. Synonym to IOTC artisanal fishery (Res. 15/02).
Conservation and Management Measure
Any measure adopted pursuant to Articles V(2)(c) and IX in the IOTC Agreement, and more generally where not applicable to IOTC such measures that are consistent with international law (IOTC CMMs).
Coordinating working party on fishery statistics
International and interorganizational forum for agreeing common definitions, classifications and standards for the collection of fishery and aquaculture statistics. It has developed common procedures for statistics collation which have streamlined processes and reduced the burden on the statistical offices of national fisheries and aquaculture production, as well as providing technical advice to participating organisations on fishery-related and aquaculture-related statistical matters, and facilitating the publication of methodological and reference documents (CWP).
D
Disc width
Length of a ray measured as the maximum straight distance between wing tips.
Discards
All non-retained catch, including individuals released alive or discarded dead (Alverson et al. 1994).
Drifting fish aggregating device
Fish aggregating device not tethered to the bottom of the ocean typically composed of a floating structure (such as a bamboo or metal raft with buoyancy provided by buoys, corks, etc.) and of a submerged structure (made of canvass, ropes, etc.) (Res. 19/02).
Drifting longline
Longline kept near the surface or at a certain depth by means of regularly spaced floats. Drifting longlines may be of considerable length, and the snoods are usually longer and more widely spaced than for the bottom longlines. Some drifting longlines are set vertically, each line hanging from a float at the surface. They are usually worked in groups of several lines operated by a single boat (Nédélec and Prado 1999).
Driftnet
Type of gillnet that is not fixed to the seabed but allowed to drift with the current. Synonym to drift gillnet (https://www.fao.org/fishery/en/geartype/220/en).
E
Elasmobranchs
Subclass of chondrichthyes or cartilaginous fish, including modern sharks (superorder Selachii), skates, rays, and sawfish (superorder Batoidea) (Wikipedia).
Engine power
Power that an engine can put out, generally expressed in kilowatt (kw) or horsepower (hp).
Exclusive economic zone
An area beyond and adjacent to the territorial sea, subject to the specific legal regime established in the United Nations Convention on the Law of the Sea, which provides that it is not to extend beyond 200 nm from the baselines from which the breadth of the territorial sea is measured.
F
Fish aggregating device
A permanent, semi-permanent or temporary object, structure or device of any material, man-made or natural, which is deployed and/or tracked, for the purpose of aggregating target tuna species for consequent capture (Res. 19/02).
Fisher
An individual who engages in fishing activities for the purpose of deriving a livelihood, generating a revenue or pursuing sport or recreation. A full-time, part-time or occasional fisher receives some or all of their livelihood from fishing or spends some or all of their working time in that occupation. A sport or recreational fisher (or angler) conducts fishing in pursuit of sport or recreation (CWP Handbook).
Fishery
An activity leading to harvesting of fish. It may involve capture of wild fish or raising of fish through aquaculture (FAO fishery glossary).
Fishery (IOTC)
IOTC definition of fishery units used to define fishing practices, which emerge from the combination of fishery purposes, area of operation, fishing vessels’ size, gear and gear configuration, and target species (see section on Terminology).
Fishery vessel
Mobile floating platform of any kind and size, operating in fresh, brackish or marine waters which are used for catching, harvesting, searching, transporting, landing, preserving and/or processing fish, shellfish and other aquatic organisms, residues and plants (CWP Handbook).
Fishing capacity
The ability of a vessel or fleet of vessels to catch fish. Fishing capacity (capacity output) can be expressed more specifically as the maximum amount of fish over a period of time (year, season) that can be produced by a fishing fleet if fully utilised, given the biomass and age structure of the fish stock and the present state of the technology (Pascoe and Greboval 2003).
Fishing effort (effective)
Adjusted measure of effort to take account of differences in fishing power and efficiency and ensure proportionality with fishing mortality, and when two or more kinds of gear are used or when the same gear is used for example by different classes of vessel or métier, the respective efforts are adjusted to some common standard before being aggregated across all classes (strata) (CWP Handbook).
Fishing effort (nominal)
General measure of effort used to quantify the unadjusted, total effort units exerted on a stock in a given time period by a fishery, gear or métier (CWP Handbook).
Fishing logbook
A permanently bound logbook issued by the flag State of a vessel and required for any purpose relating to fishing or related activities, with irremovable pages, each of which is consecutively numbered and printed with an applicable serial number and/or an electronic logbook, being computerised record of information and data relating to fishing or related activities in such template as may be required, including under any conservation and management measure.
Fishing mode
A specific practice or method of conducting a fishing operation or searching for fish within a fishery, fishing sector or region. A fishing mode may also be associated with a métier (CWP Handbook).
Fishing power
Effectiveness of a vessel’s fishing effort relative to the effectiveness of other vessels.
Fishing vessel
Fishery vessel only engaged in catching operations. The term “non-fishing vessel” applies to vessels performing other functions related to fisheries; this includes vessels providing supplies, motherships, fish carriers, and vessels involved in fisheries resources protection, aquaculture operations, and vessels rendering assistance or conducting fisheries related research or training (Thermes et al. 2003).
Flag state
The State in which a vessel is registered, providing it is only registered in one State.
Fork length
Length of a fish measured as the straight distance between the tip of the snout and the fork of the tail.
Free school
The fish school is not associated with any anchored or drifting floating object. Synonym to free-swimming school or unassociated school.
G
Gear
The general name for the equipment used for fishing. This might include lines, nets, warps, floats, deck equipment and any other specific fishing items (Thermes et al. 2023).
Gillnet
Type of passive fishing gear consisting of panels of net held vertically in the water column, either in contact with the seabed or suspended from the sea surface, such that fish attempting to swim through the net are entangled. The mesh size of the net determines the size range of fish caught, as smaller fish can swim through the meshes and larger fish are not enmeshed (https://www.fish.wa.gov.au/).
Gross tonnage
Dimensionless measure of the overall size of a ship (Thermes et al. 2023).
H
Handline
Fishing method in which a line with a hook, usually baited, is lowered into the water from a drifting, anchored or moving fishing vessel or from a jetty, pier or rock on the shore overlooking the water (Bjarnason 1992).
High-seas
All parts of the sea that are not included in the exclusive economic zone, in the territorial sea or in the internal waters of a State, or in the archipelagic waters of an archipelagic State (UNCLOS).
I
Industrial fishery
Fishery that (i) catches fish from large and medium-sized vessels fitted out with mechanised methods of operating the fishing gear and installations for preservation of fish on board, (ii) process the catch either in land base or on board – in which cases the vessels are provided with appropriate processing installations, and (iii) distribute the fish products around the country and abroad using mechanised means of transportation adapted for fish and fish products. All these activities are generally organised for the financial benefit of the companies or organisations operating the fishing vessels, processing plants, and fish product transportation (Thermes et al. 2023).
Industrial fishing vessel
Large vessel, typically of 24 m in length and over, engaged in catching operations, outfitted with mechanised methods of operating the fishing gear and installations for preservation of fish on board (Thermes et al. 2023).
IOTC active vessel list
The list of vessels having operated in the IOTC area of competence in a given year, including fishing and non-fishing vessels of 24 m length overall and over, or of less than 24 m length overall that operated in waters outside the economic exclusive zone of the flag State (Res. 10/08).
IOTC Agreement
The 1993 Agreement for the establishment of the Indian Ocean Tuna Commission (IOTC Agreement)
IOTC area of competence
The Indian Ocean (defined for the purpose of the IOTC Agreement as being FAO Statistical Areas 51 and 57), and adjacent seas, north of the Antarctic Convergence, insofar as it is necessary to cover such seas for the purpose of conserving and managing stocks that migrate into or out of the Indian Ocean. In 1999, the Commission extended the western boundary of the IOTC statistical area from 30ºE to 20ºE, thus eliminating the gap in between the areas covered by the IOTC and ICCAT (FAO Fisheries Geonetwork Platform).
IOTC record of authorised vessels
The list of vessels authorised to operate in the IOTC Area of Competence in a given time period, including fishing and non-fishing vessels of 24 m length overall and over, or of less than 24 m length overall that may operate in waters outside the economic exclusive zone of the flag State. These vessels are referred to as authorised fishing vessels (AFVs) (Res. 19/04).
IOTC species
Any or all of the 16 tuna and tuna-like species listed in Annex B of the IOTC Agreement.
IOTC stocks
The populations of the IOTC species which are located in the IOTC area of competence or migrate into or out of the area IOTC Agreement.
Instrumented buoy
A buoy with a clearly marked with a unique reference number allowing identification of its owner and equipped with a satellite tracking system to monitor its position (Res. 19/02).
L
Landing
Weight of what is landed at a landing site. May be different from the catch which includes the discards (FAO fishery glossary).
Large-scale driftnets
Drift gillnets or other nets or a combination of nets that are more than 2.5 km in length whose purpose is to enmesh, entrap, or entangle fish by drifting on the surface of or in the water column.
Length overall
Distance in a straight line parallel to the design waterline, between the foremost point of the bow and the aftermost point of the stern (Thermes et al. 2023).
Line fishing
Fishing methods that use fishing lines in one form or another, including handlines, hand reels, powered reels, pole-and-lines, droplines, longlines, trotlines, and trolling lines.
Live weight equivalent
Weight derived from the landed or product weight by the application of certain factors and designed to represent the actual weight of the fishery product as it was taken from the water and before being subjected to any processing or other operations (Eurostat).
Longline fishery (IOTC)
Fishery undertaken by vessels recorded in the IOTC Record of Authorised Vessels that use a longline gear (Res. 15/02).
Longline
A fishing gear in which branch lines (called snoods or gangions) carrying baited or unbaited hooks are attached to a longer main line at regular intervals. A snood is a short length of line, attached to the main line using a clip or swivel, with the hook at the other end. Longlines are classified mainly by where they are placed in the water column. They can be laid on the bottom or suspended horizontally at a predetermined depth with the help of surface floats. The main lines can be as long as 150 km and have several thousand hooks (FAO fishery glossary).
Lower-jaw fork length
Length of a fish measured as the straight distance between the tip of the lower jaw and the fork of the tail.
M
Metadata
Description of the the content, context and provenance of datasets in a standardised and structured manner, typically describing the purpose, origin, temporal characteristics, geographic location, authorship, access, and conditions and terms of use of a dataset (UK data service).
N
Neritic
Designating, or of, the ecological zone (neritic zone) of the continental shelf extending from low tide to a depth of around 180 m.
Net tonnage
Dimensionless measure of the useful capacity of a ship (Thermes et al. 2023).
Nominal catches
Officially declared aquatic organisms captured during fisheries and expressed as live weight equivalent. Nominal catches do not include unreported catches, such as unreported discards, and may differ considerably from the real catch (Eurostat).
Non-target species
Species that are unintentionally taken by a fishery or not routinely assessed for fisheries management.
O
Oceanic
Open-ocean waters beyond the edge of the continental shelf.
Operational buoy
Any instrumented buoy, previously activated, switched on and deployed at sea on a drifting FAD or log, which transmits position and any other available information such as echo-sounder estimates (Res. 19/02).
P
Pelagic
Inhabiting surface waters rather than the sea floor. Usually applied to free-swimming species such as tunas and sharks.
Pole-and-line fishing
A fishing technique in which surface schooling fish are attracted to the vessel and driven into very active feeding behaviour by throwing live or dead bait into the water and spraying water onto the sea surface to simulate the escape behaviour of small preys. The fish lured with a line and a hook attached to a pole and pulled off the water by manual or powered devices (FAO fishery glossary).
R
Retained catches
Estimated component of the catch which is retained on board during a fishing trip (CWP).
Round weight
Weight of the whole fish before processing or removal of any part (FAO fishery glossary).
Purse seine
Nets characterized by the use of a purse line at the bottom of the net. The purse line enables the net to be closed like a purse and thus retain all the fish caught (Nédélec and Prado 1990).
S
Semi-industrial fishery
Fishery that (i) catches fish from medium- (and/or small-) sized vessels fitted out with mechanised methods of operating the fishing gear, (ii) process the catch in land bases, and (iii) distributed the fish and fish products around a limited area, and in exceptional cases only for export. These activities are aimed at the financial benefit of the companies or organisations operating the fishing vessels, processing plants, and transport facilities (Thermes et al. 2023).
Semi-industrial fishing vessel
Medium-sized vessel, typically of 12 m in length but less than 24 m in length, engaged in catching operations, outfitted with mechanised methods of operating the fishing gear (Thermes et al. 2023).
Set longline
Longline consisting of a main line set either horizontally on or near the bottom or less commonly near the surface (Nédélec and Prado 1990).
Size-frequency
The number of individuals in a catch or catch sample in each group of sizes (size intervals).
Small-scale fishery
Fishery characterised in most cases by fishing vessels with non-mechanized propulsion systems (sails and oars) or low-horsepower outboard or inboard engines, use of passive fishing methods, manual operation of fishing gear (setting, shooting and hauling) and the absence of electronic fish-finding and navigational devices (Tietze et al. 2000). From a socio-economic perspective, small-scale fisheries can be broadly categorised as a dynamic and evolving sector employing labour intensive harvesting, processing and distribution technologies to exploit marine and inland water fishery resources. The activities of this sub-sector, conducted full-time or part-time, or just seasonally, are often targeted on supplying fish and fishery products to local and domestic markets, and for subsistence consumption (FAO 2004).
Standard length
Length of a fish measured as the straight distance between the tip of the snout to the end of the caudal skeleton (FAO fishery glossary).
Subsistence fishery
Subsistence fishery is a fishery where the fish caught are consumed directly by the families of the fishers rather than being bought by middle-(wo)men and sold at the next larger market (FAO 1999).
Support vessel
Non-fishing vessel supporting fishing operations and in particular assisting purse seine fishing vessels in the location of tuna schools and in the the deployment, monitoring and retrieving of buoys and drifting fish aggregating devices. Synonym to supply vessel, auxiliary vessel or tender vessel.
Surface fishery
Fishing activity to target surface-swimming species.
Surface fishery (IOTC)
Fishery undertaken by vessels recorded in the IOTC Record of Authorised Vessels other than longline fisheries; in particular purse seine, pole-and-line, gillnet, handline, and trolling vessels (Res. 15/02).
T
Tonnage
A measure of the size or capacity of a ship, representing a dimensionless function of volume which is defined by internationally agreed formulae (Thermes et al. 2023).
Trolling line
Simple line, provided with natural or artificial bait and trailed near the surface or at a certain depth by a vessel. Several lines are usually towed at the same time, by using outriggers (Nédélec and Prado 1990).
U
Upper-jaw fork length
Length of a fish measured as the straight distance between the tip of the upper jaw and the fork of the tail.