Thunnus atlanticus is found in coastal waters with a temperature above 20°C. It is an epipelagic species, often found over reefs, bays and offshore. It sometimes occurs in large schools, often with Skipjack Tuna (Katsuwonus pelamis). It feeds on fishes, squids and crustaceans. The IGFA all-tackle gamefish record for this species was caught off the coast of Florida and weighed 22.4 kg. Maximum recorded length is 110 cm fork length (FL) (Collette 2010).

Around Florida, spawning season extends from April to November, with a peak in May, while in the Gulf of Mexico spawning apparently occurs between June to September (Collette 2010). In Brazil, spawning peaks in November and December. The species migrates to Formosa Bay to spawn from October to January (Freire 2009). During the spawning season, there is an annual concentration of T. atlanticus along the southern coast of Rio Grande do Norte during the second half of the year (Vieira et al. 2005a).

Vieira et al. (2005b) found an average length of 61.1 cm for females and 64 cm for males. The total weight ranged from 1,000 to 5,000 g (females) and 1,456 to 8,400 g (males) for individuals caught in Rio Grande do Norte from September 1999 to January 2001, within a depth range of 20–60 m. The same authors report a sex ratio of 2.1:0.5, with a larger abundance of males. Freire (2009) reports captures of T. atlanticus from 36–89 cm FL along the northeastern Brazilian coast between 1998 and 2000.

According to Vieira et al. (2005b), the estimated average length for gonadal maturation is 51 cm total length (TL) for females and the absolute fecundity shows a mean of 1,541,841 oocytes for specimens caught in Rio Grande do Norte State, Brazil. Freire (2009) report size at first maturity at 49.2 cm (TL) for females and 51.3 cm (TL) for males.

Tagging data exists from the Caribbean Regional Fisheries Mechanism (CRFM) for this species (787 individuals). This data does not indicate migratory behavior (Singh-Renton and Renton 2007). There is evidence of genetic differentiation between the Gulf of Mexico and Northwest Atlantic stocks (Saxton 2009).

Maximum size is 100 cm FL. The all-tackle game fish record is of a 22.39 kg fish caught off Marathon, Florida in 2006 (IGFA 2011).

GBGC7868-09|DQ835881|Thunnus atlanticus| ------------------------------------------------------------------------------------------------------------------------------------------------TTG---------------------------------------------------TTTATAGTAATACCAATTATGATTGGAGGATTTGGAAACTGACTTATTCCTCTAATG---ATCGGAGCCCCCGACATGGCATTCCCACGAATGAACAACATGAGCTTCTGACTCCTTCCTCCCTCTTTCCTTCTGCTCCTAGCTTCTTCAGGAGTTGAGGCTGGAGCCGGAACCGGTTGAACAGTCTACCCTCCCCTTGCCGGCAACCTGGCCCACGCAGGGGCATCAGTTGACCTA---ACTATTTGCTCACTTCACTTAGCAGGGGTTTCCTCAATTCTTGGGGCAATTAACTTCATCACAACAATTATCAATATGAAACCTGCAGCTATTTCTCAGTATCAAACACCACTGTTTGTATGAGCTGTACTAATTACAGCTGTTCTTCTCCTACTTTCCCTTCCAGTCCTTGCCGCT---GGTATTACGATGCTCCTTACAGACCGAAACCTAAATACAACCTTCTTCGACCCTGCAGGAGGGGGAGACCCAATCCTTTACCAACACCTATTCTGATTCTTTGGACATCCAGAAGTCTACATTCTTATTCTTCCCGGATTCGGAATGATCTCCCACATTGTTGCCTACTACTCAGGTAAAAAA---GAACCTTTCGGCTACATGGGTATGGTATGAGCCATGATGGCTATCGGCCTACTAGGGTTCATCGTATGAGCCCACCACATGTTCACGGTAGGAATGG 
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Red List Category

Red List Criteria

Year Assessed

Assessor/s

Reviewer/s

Contributor/s

Justification

History

• 2010
  Least Concern
  (IUCN 2010.4)

Thunnus atlanticus is one of the most common tuna species in the western central Atlantic.

FAO landings (2008) indicate that it is harvested by a wide range of countries with catches fluctuating over the last 20 years between 2,400–5,200 mt from 1986–2006. These landings probably do not include the recreational catch which likely comprises a large portion of the fishery (B. Collette pers. comm. 2009). There is some doubt as to whether this includes all catches throughout its range. Large fluctuations reflect discontinued reporting from a number of areas.

T. atlanticus was the species with the highest abundance in the pelagic longline fishery in northeast Brazil, with an average catch per unit effort (CPUE) of 0.32 ind/100 hooks, representing 56.2% of all caught tunas (Hazin et al. 2001 in MMA 2006).

Stable

This species is fished by trolling or drifting longline with live bait. Fish aggregating devices (FADs) are used to increase the capture of this species (Taquet et al. 2000). Males are caught more often than females; in one report males constituted 80% of the catch (Taquet et al. 2000). The largest fishery for this species is off the southeastern shore of Cuba (Collette 2002). It is the target of hand and line artisanal fisheries in the northeast of Brazil (Freire 2009). This species may also be taken as bycatch in the Yellowfin Tuna (Thunnus albacares) fisheries (González-Ania et al. 2001). There is also an important sport fishery in Florida and the Bahamas (Collette 2002).

Three of the major fisheries (Cuba, Dominican Republic and Martinique) have ceased reporting landings data for this species (ICCAT SCRS 2009).

Nóbrega et al. (2009) report T. atlanticus captures all along the northeastern Brazilian coast by hand-line artisanal fishery, with catches by state as follows: Bahia (57.6%), Rio Grande do Norte (23.7%), Alagoas and Pernambuco (17.7%), Ceará (0.8%) and Piauí (0.1%). There is an annual concentration of this species along the southern coast of Rio Grande do Norte State during the second half of the year which increases its capture by the artisanal fleet (Vieira et al. 2005b). It is fished all over the Brazilian central coast (from southern Bahia to northern Rio de Janeiro State) by trolling and hand-line fisheries (MMA 2006). It is also caught by game fisheries off the coast of São Paulo State (Amorim and Silva 2005).

There are no known species-specific conservation measures in place for Thunnus atlanticus.

Freire (2009) suggest a capture-release study, involving Caribbean and Brazilian northeastern and southeastern researches to better establish fishing mortality rates and understand migratory patterns.

Better data is needed from fisheries landings to specifically identify and record this species.