SANBI IDentifyIt - SpeciesSANBI IDentifyIt - SpeciesYellowfin Tuna - Thunnus albacaresYellowfin Tuna - Thunnus albacares

Geographic location / distributionGeographic location / distribution

Habitat : Yellowfin is found worldwide in open water in tropical and subtropical seas. They prefer warm water and are

commonly found in water of 22°C (not below 8°C). Although they can dive to 350m depths, they are usually found in the

top 100m of the sea surface.

Found in SA waters: In the Atlantic, Yellowfin are predominantly found in the SW Cape region from spring to summer. By

June they move south due to the increased north west wind in the winter months, which is reflected in the catches and

the seasonality of the tuna pole fishery.

Generally Yellowfin is more abundant in the Agulhas Current.

It is suspected that the Indian and Atlantic Ocean populations around South Africa are separate stocks.

FisheryFishery

Yellowfin is targeted by both the tuna longline and tuna pole fisheries in South Africa.

The tuna pole fishery is a small fishery which lands the majority of yellowfin fresh for the export market, and has a

fishing season from September - April each year, coinciding with the best seasons for Albacore and Yellowfin. Using a

pole and line is a selective form of fishing and not much bycatch is caught. However, seabirds and sharks do

occasionally get caught on the line and should be released alive. Other fish species are caught and are managed by

catch limits:

Daily bag limit of 10 yellowtail per crew member

Species not allowed to be caught: Chokka and Mackerel spp.

Longlining is not a very selective form of fishing and many species are caught accidentally on the the hooks. Bycatch

species in this fishery include: billfishes (swordfish, marlins etc), seabirds, turtles and sharks. Recent assessments show

that eleven species of seabird, four species of turtle and 20 species of shark are caught incidentally by this fishery. The

FAO estimates that approximately 28% of the catch is discarded. Local studies indicate that discards comprise

approximately 22% of the catch. Bycatch restrictions therefore exist to protect vulnerable species:

The bycatch of billfish cannot exceed 10% of the total tuna catch

A precautionary catch limit of 25 seabirds has been set for tuna longline vessels, after which further management

restrictions are enforced

Shark fins need to be landed with their trunks, with the fins not exceeding 5% of the weight of the trunk

Any Bigeye, Swordfish or Southern Bluefin tuna landed must be accompanies by the relevant RFMO (ICCAT, IOTC or

CCSBT) catch statistical document.

Size l imitsSize l imits

Southern bluefin tuna >6.4kg

Bigeye tuna >3.2kg

Yellowfin tuna >3.2kg

Swordfish >119cm LJFL / >18kg dressed

Marlins >210cm LJFL

Stock statusStock status

Indian ocean - Overfished

Atlantic ocean - Overfished in recent years, and showing signs of recovery, although this is uncertain

Fisheries managementFisheries management

Yellowfin falls within the management of the large pelagic fishery, and due to its widespread and migratory habits in

Photo: NOAA

both oceans, it is managed by Regional Fisheries Management Organisations in the Atlantic and Indian Oceans. South

Africa is a member of ICCAT and a co-operating non-member of IOTC and CCSBT. Although RFMO's manage high seas

fisheries, management recommendations and resolutions are implemented by South Africa through national legislation

and permit conditions.

Tuna is managed by a Total Allowable Effort (TAE), meaning that instead of setting a limit on the catch, a limit is set on

the number of rights holders allowed to catch tuna. Currently there is a limit of 200 rights holders in SA (including pole

and longline).

Maturity and SizesMaturity and Sizes

Yellowfin reach maturity after 2.5-3 years, at a size of (on average) 100-110cm (20-30 kg). Maximum FL = over 200cm.

Physical descriptionPhysical description

Yellowfin's flesh tends to be firmer than that of Bigeye tuna, and does not retain the natural red pigmentation as long

Yellowfin meat is much more red than other species, especially Longfin.

Other similar speciesOther similar species

Thunnus alalunga - Albacore/Longfin Tuna

Thunnus obesus - Big-Eye Tuna

Thunnus maccoyii - Southern Bluefin Tuna

Katsuwonus pelamis - Skipjack Tuna

ReferencesReferences

SASSI status http://www.wwfsassi.co.za/?m=5&s=5&idkey=1118http://www.wwfsassi.co.za/?m=5&s=5&idkey=1118

FAO fact sheets http://www.fao.org/fishery/species/2498/enhttp://www.fao.org/fishery/species/2498/en

Fishery Resource Monitoring System: http://firms.fao.org/firms/resource/9/enhttp://firms.fao.org/firms/resource/9/en

ICCAT Tuna fact sheets. ICAT Manual. January 2010.

FAO. © 2006-2010. Fisheries and Aquaculture Department. Biological characteristics of tuna/Individual species sheets. FI

Institutional Websites. Text by Michel Goujon and Jacek Majkowski. In: FAO Fisheries and Aquaculture

Department[online]. Rome. Updated 24 February 2010. [Cited 30 November 2010]. Website:

http://www.fao.org/fishery/topic/16082/enhttp://www.fao.org/fishery/topic/16082/en

Photo: Taro Taylor

Photo: Allen Shimada, NOAA NMFS OST

Photo: www.hiwtc.com/products/india-ocean-yellowfin-tuna-526-4692.htm

Photo: NOAA

General

Southern Bluefin Tuna vs Yellowfin Tuna

Photo: William B. Folsom, NMFS

Tuna Comparison Copy right/Websi te:Copy right/Websi te: TRAFFIC

Tuna Trade Products Copy right/Websi te:Copy right/Websi te: TRAFFIC

General Tuna Identification Photo: Food and Agricultural Organisation

(FAO)

P hotographer:P hotographer: Food and Agricultural Organisation (FAO)

20008-2010

Copy right/Websi te:Copy right/Websi te: FAO 20008-

2010

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