Global monthly catches from tuna fisheries by 1° and 5° grids (1950-2021) (FIRMS level 0)

Description

Methods (English)

Tuna Regional Fisheries Management Organizations (t-RFMOs) are regional fishery bodies responsible for the conservation and management of tuna and tuna-like species, associated species, and their ecosystems across the Atlantic, Indian, and Pacific Oceans. T-RFMOS routinely collate and consolidate fisheries data from their Contracting Parties to inform the scientific advice guiding the management process.

The dataset was compiled using publicly available monthly geo-referenced catch data curated and disseminated by the five t-RFMOs: the Commission for the Conservation of Southern Bluefin Tuna (CCSBT), the Inter-American Tropical Tuna Commission (IATTC), the International Commission for the Conservation of Atlantic Tunas (ICCAT), the Indian Ocean Tuna Commission (IOTC), and the Western and Central Pacific Fisheries Commission (WCPFC). The retained data encompasses all fishing gears characterized by a monthly temporal resolution and a spatial resolution of 1° or 5° of longitude and latitude.

The description of each original input dataset can be found at the following links:

- CCSBT: https://www.ccsbt.org/en/content/sbt-data
- IATTC: https://www.iattc.org/en-US/Data/Public-domain
- ICCAT: https://www.iccat.int/en/accesingdb.html
- IOTC: https://iotc.org/data/datasets/latest/CE/All
- WCPFC: https://www.wcpfc.int/public-domain

"FIRMS level 0" refers to the initial stage where the primary datasets undergo processing to form the dataset. The creation of the global FIRMS level 0 dataset involves several sequential steps:

1. Preparation: For confidentiality reasons, details regarding flag state and fishing mode for the geo-referenced catches of the eastern Pacific Ocean purse seine fisheries are available in separate files. For the purposes of the GTA, the catch data from the flag-detailed dataset was scaled up to match the catch data from the school type-detailed dataset. This adjustment was made to estimate catches by both flag state and fishing mode within each stratum. To avoid double-counting catches due to overlapping areas of competence between the IOTC, WCPFC, and IATTC, catch data from the IOTC and IATTC were retained in the dataset. This is because the WCPFC data were filtered at the source to exclude all strata with observations from fewer than four vessels, reducing their accuracy. This filtering process follows WCPFC's rules and procedures for the protection, access, and dissemination of data (https://www.wcpfc.int/doc/data-02/rules-and-procedures-protection-access-and-dissemination-data-compiled-commission).
2. Submission: Public domain datasets from CCSBT, IATTC, ICCAT, IOTC, and WCPFC were submitted through the FIRMS Global Tuna Atlas data collection framework at https://i-marine.d4science.org/group/fao_tunaatlas/dcrf-data-call-management. Data were submitted according to the CWP Reference Harmonization standard (https://www.fao.org/3/cc6734en/cc6734en.pdf) using a GTA catch common data format (https://github.com/fdiwg/fdi-formats/blob/main/cwp_rh_generic_gta_taskI.json). It is noteworthy that certain original codes used within t-RFMOs could not be mapped to standard codelists, especially those representing an aggregation of other existing codes, e.g., IDPH - Indonesia and Philippines as fishing fleet code for the WCPFC. Due to WCPFC confidentiality policies, information on fishing fleet in data available at a resolution of one month and 1° or 5° of longitude and latitude is only available for fisheries occurring in the Western Pacific Ocean that use drifting longlines. The fishing fleet was set to NEI for all fisheries using purse seines, gillnets, and pole-and-lines.
3. Binding: This step involves combining the individual geo-referenced catch datasets provided by the t-RFMOs into a single dataset.
4. Filtering: Data for southern bluefin tuna (Thunnus maccoyii) from t-RFMOs other than the CCSBT were excluded. CCSBT is considered the authoritative source of information for this species. Data available at a lower spatial resolution than 5° longitude and latitude were excluded from the dataset. Data available at a temporal resolution lower than monthly were excluded from the dataset.
5. Services: The dataset was loaded in the Tuna atlas database, the FAO Fisheries & Aquaculture Spatial Data Infrastructure (GeoServer at https://www.fao.org/fishery/geoserver and GeoNetwork https://www.fao.org/fishery/geonetwork ) and underlying Global Tuna Atlas map viewer https://www.fao.org/fishery/geoserver/tunaatlas/
6. Publication: The dataset was published on the Zenodo platform with the following DOI: https://zenodo.org/doi/10.5281/zenodo.5747174