Thunnus albacares
None
South Africa (Atlantic and Indian Oceans) - FAO Area 47
Orange (CURRENTLY UNDER REVISION) *
Yellowfin tuna is an open ocean fish, rarely found near reefs. It is a relatively a long-lived tuna species (maximum age of 9 years) with a moderate to high intrinsic vulnerability. It is highly valued for sashimi and regularly served in restaurants. Atlantic Ocean Yellowfin tuna was overfished in recent years, but is showing some signs of recovery. However, the level of uncertainty is very high, with a 60% chance that the stock indicators are outside the MSY (maximum sustainable yield) margins and the declining trend in average weight is also a cause for concern. Indian Ocean Yellowfin tuna is also considered overfished; fishing mortality has recently exceeded the Maximum Sustainable Yield (MSY)-related level, therefore some reduction in catch or fishing effort would be required to return exploitation rates to those related to MSY.
As a coastal state that has ratified the United Nations Fish Stocks Agreement, South Africa is obliged to develop and manage a fishery for large pelagic species in cooperation with the relevant Regional Fisheries Management Organisations (RFMOs) and in accordance with their existing management and control measures. The large pelagic fishery is thus managed by RFMOs (such as the International Commission for the Conservation of Atlantic Tuna (ICCAT), the Indian Ocean Tuna Commission (IOTC) and the Commission for the Conservation of Southern Bluefin Tuna (CCSBT). 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. There is however a lack of strong management from RFMOs, which is of concern given that this fishery relies on high seas stocks.
In South Africa, this fishery uses pelagic longline fishing gear which has a negligible habitat effect since they are not used near the bottom. However, a number of vulnerable species are caught as bycatch; 11 species of seabird, four species of turtle and 20 species of shark have been confirmed incidentally caught by this fishery, many of which are considered threatened and for which fishing has been identified as the predominant cause for recent population declines. The United Nations� Food and Agriculture (FAO) estimates that approximately 28% of the catch is discarded. Local studies indicate that discards comprise approximately 22% of the catch. Many of the world�s large predatory fish are considered over-fished and evidence from elsewhere suggests that decreases in top predator populations can have ramifications for the functioning of pelagic ecosystems. However, South Africa has relatively good management in place that addresses most relevant concerns. However, the management of vulnerable bycatch species, in particular sharks, requires further attention.
*Please note, Yellowfin Tuna is currently under revision in terms of its WWF-SASSI sustainability rating, and more recent information incorporated into the assessment may affect its colour categorisation.
For more information, email us at sassi@wwf.org.za.
Rather choose a green-listed alternative such as pole-caught tuna or queen mackerel. These alternatives have similar meaty, firm and rich flesh as local longline yellowfin tuna. Or if you don�t want to cut local longline caught yellowfin tuna out of your diet completely, eat it on a special occasion rather than every time you eat out.