Skipjack tuna

The last stock assessment completed for Eastern Atlantic Skipjack tuna was completed in 2014, and used catch data up to 2013 (ICCAT 2014b). Methods used in recent skipjack tuna stock assessments included a Catch-only model, and Bayesian Surplus Production Model (ICCAT 20014b).

The Scientific Committee has suggested keeping catches of skipjack tuna below recent levels {ICCAT 2014}.

Last updated on 08 Jan 2015

Source: ICCAT (2014).
MSY: 143,000 – 170,000 tonnes
Current Replacement Yield: 203,500 tonnes
B2008/Bmsy: likely >1
F2008/Fmsy: likely <1

The most recent stock assessment suggests that Skipjack tuna stock in Eastern Atlantic is not overfished and overfishing is not occurring (ICCAT 2014).

Last updated on 08 Jan 2015

Skipjack tuna catches in the eastern Atlantic have been increasing over time. In recent years, catches have exceeded 200,000 t {ICCAT 2014}.

The International Commission for the Conservation of Atlantic Tunas (ICCAT) has not established any management measures specific to skipjack tuna. However, the establishment of a time area closure in the surface fishery to protect juvenile bigeye tuna also provides some protection to skipjack. In addition, area closures to FAD fishing during January and February (2013) will likely have an impact on skipjack tuna {ICCAT 2012a}.

Last updated on 08 Jan 2015

Skipjack tuna populations are currently healthy and there is no recovery plan in place {ICCAT 2014b}.

There is no TAC in place for skipjack tuna {ICCAT 2014}.

Bycatch of sea turtles can occur in purse seine and longline fisheries. In the Atlantic Ocean, green, hawksbill, leatherback, loggerhead and olive ridley sea turtles have the potential to be incidentally captured in these fisheries. Green, leatherback, and loggerhead sea turtles have been classified as Endangered by the International Union for the Conservation of Nature (IUCN), hawksbill as Critically Endangered and olive Ridley as Vulnerable (Seminoff 2004)(Mortimer and Donnelly 2008)(TEWG 2007)(MTSG 2006)(Abreu-Grobis and Plotkin 2008). Purse seines are prohibited from setting around sea turtles and any incidentally captured sea turtles (purse seine or longline cpatured) must be released using safe handling techniques (ICCAT 2010a).Several species of sharks, silky, oceanic whitetip and hammerhead sharks are prohibited from being retained if incidentally captured {ICCAT 2011b}{ICCAT 2010b}{ICCAT 2010c}.

In Atlantic purse seine (associated) fisheries, billfish, bony fish, other tuna species and sharks can be incidentally captured. Bycatch in unassociated purse seine fisheries typically consists of fewer species and occurs in less amounts. Observer rerecords from French and Spanish purse seiners indicate that blue marlin, dolphinfish, rainbow runner, triggerfish, silky and oceanic whitetip sharks are bycatch species in associated fisheries(Amande et al. 2010). Blue marlin are currently fished at unsustainable levels (ICCAT 2011a). Bycatch in fisheries such as purse seine are considered to be a contributing factor to silky shark population declines (Bonfil 20009). The status of the other species is unknown in the Atlantic. In unassociated fisheries, Atlantic sailfish have been reported as a common bycatch species (Chassot et al. 2008). Atlantic sailfish populations in the eastern Atlantic are likely undergoing overfishing (ICCAT 2009).

Under the International Commission for the Conservation of Atlantic Tunas (ICCAT), countries are required to report bycatch and discards. In addition, several species of sharks, silky, oceanic whitetip and hammerhead, are prohibited from being retained if incidentally captured {ICCAT 2011b}{ICCAT 2010b}{ICCAT 2010c}. Management measures for other bycatch species, such as dolphinfish, wahoo, rainbow runner and triggerfish are not in place.

Purse seines typically have minimal impact to bottom habitats. Unassociated purse seines do not come in contact with bottom habitats. Anchored fish aggregating devices (FADs) could result in contact with the bottom {Beverly et al. 2012).

Last updated on 09 Dec 2009

There is a time area closure for the surface fishery and area closures for fishing with fish aggregating devices (FADs) during January and February {ICCAT 2012a}.