Taxonomy- Blackfin tuna (Thunnus atlanticus) is the smallest tuna species in the Thunnus genus, which includes all true tunas.
Species
of Commercial Interest
- The designation “Blackfin” refers to a single species, Thunnus atlanticus.
Distribution
- Blackfin tuna have a limited range and occur only in the western Atlantic Ocean approximately from the Massachusetts coast of the United States south to Rio de Janeiro in Brazil. There is a recent record (2008) from Saint Peter and Saint Paul Archipelago.
Biology
- Blackfin tuna are one of the lesser-studied species, making it difficult to evaluate their stock status. What is know is that they exhibit life history characteristics making them inherently resilient to fishing pressure: low age at maturity, short life span and a fast growth rate. They are most often found in coastal waters with a temperature above 20°C, congregating over reefs, bays, and offshore. They have been known join in large schools, often with Skipjack Tuna. This is a species that feeds on fishes, squids and crustaceans.
- Blackfin tuna reproduce at a young age (app. 2 years) and grow quickly. 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. In Brazil, spawning peaks in November and December.
Sustainability
- IUCN Red List Status: Least Concern (LC)
- MBA Seafood Watch:
- Blackfin tuna is often caught in fisheries that target other tuna species, such as skipjack. They are primarily caught by trolling or purse seines, but handlines, rod-and-reel, and longlines are also used. Of these, trolling, handlines, and rod-and-reel are preferred because they produce less bycatch. Longlines may result in high bycatch, including undersized tuna and endangered species such as sea turtles, sharks and seabirds. The purse seine fishery also has high bycatch when used with fish aggregating devices (FADs) as these floating devices also attract turtles, sharks and other species that end up in the nets, dead or dying.
Potential
Health Concerns
- Environmental Defense Fund has issued a health advisory for Blackfin tuna due to elevated levels of mercury.
