Monthly fishing effort targetting tuna, tuna-like and shark species in the Indian Ocean (1970-2015) by gillneters, lines and unclassifed gears aggregated by 1° or 5° squares (IOTC level 0)

This dataset lists fishing efforts targetting tuna, tuna-like and shark species from the Indian Ocean Tuna Commission (IOTC) by coastal fisheries from 1970 to 2015. Efforts are stratified by year, month, fishing gear, vessel flag reporting country, unit of effort, area (mainly 5° squares). It corresponds to the effort part of the IOTC catch-and-effort (task2) dataset.

Efforts are expressed in several units : number of boats, number of days at sea, number of fishing days, number of hooks, number of hours fishing, number of lines (poles), number of trips, net-days. The unit of effort depends on the stratum (i.e. association of the year, fishing gear, vessel flag reporting country). Only one single unit of effort is available for a given stratum.

This dataset was downloaded on the IOTC website. It was then restructured to be in line with the Sardara database structure (columns normalization, names, etc.). However the content of data and the code lists were kept exactly as their are available in the source dataset.

The description below (caracteristics, specific issues and problems that need to be taken into account) is extracted from the IOTC web page where the dataset has been downloaded.

Caracteristics, specific issues and problems that need to be taken into account :

Catches and effort are not available for all Nominal catches strata. When recorded, the catches in these datasets might represent the total catches of the species in the year for the fleet and gear concerned or represent simply a sample of those. These data are considered to be in the public domain, provided that the catch of no individual vessel can be identified within a time/area stratum. In cases when an individual vessel can be identified, the data are aggregated prior to release by time, area or flag to preclude such identification, and will then be in the public domain. Catch-and-effort and length-frequency data grouped at a finer level of time-area stratification are only released with written authorization from the sources of the data and are subject to a number of constraints destined to preserve confidentiality.

Dataset extent

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Field Value
Additional Info
Field Value
access_constraints []
bbox-east-long 150
bbox-north-lat 30
bbox-south-lat -46
bbox-west-long 20
[{"type": "revision", "value": "2018-01-08"}]
frequency-of-update annually
graphic-preview-description Thumbnail from WMS / Geoserver
graphic-preview-type WWW:LINK-1.0-http--link
GUID indian_ocean_effort_tunaatlasIOTC_level0__coastal
licence []
metadata-date 2018-01-08T10:38:21
metadata-language eng
point_of_contact 1 IRD -,
point_of_contact 2 Fiorellato Fabio,
progress tentative
resource-type dataset
[{"name": "Institut de recherche pour le d\u00e9veloppement (IRD)", "roles": ["publisher"]}, {"name": "Indian Ocean Tuna Commission (IOTC)", "roles": ["originator"]}]
{"type": "Polygon", "coordinates": [[[20.0, -46.0], [150.0, -46.0], [150.0, 30.0], [20.0, 30.0], [20.0, -46.0]]]}
spatial-data-service-type OGC Web-Service
spatial-reference-system 4326
spatial_harvester true
system:type Dataset
temporal-extent-begin 1970-01-01T00:00:00
temporal-extent-end 2015-08-01T00:00:00
Management Info
Field Value
Author Indian Ocean Tuna Commission (IOTC),Observatory of Exploited Tropical Pelagic Ecosystems, MARBEC Research Unit 248, IRD,IRD, UMR MARBEC & COI,FAO - Fisheries and Aquaculture Department (FI). Fisheries and Aquaculture Policy and Resources Division (FIA)
Maintainer iMarine Catalogue Manager
Last Updated 26 August 2021, 16:04 (CEST)
Created 26 August 2021, 16:04 (CEST)