The conservation status of tuna is complex, as “tuna” refers to several distinct species, each with its own status. Some populations have faced severe declines, while others remain stable. This variation highlights a global challenge involving ecological factors and human activity. Understanding each species’ situation and protection efforts is important for grasping the full picture of tuna conservation.
Conservation Status of Tuna Species
The International Union for Conservation of Nature (IUCN) Red List provides comprehensive assessments of species’ conservation statuses. Southern Bluefin Tuna (Thunnus maccoyii) is categorized as Endangered, an improvement from its Critically Endangered status in 2021 due to population increases. Despite this, it remains heavily impacted by overfishing. This highly migratory species grows large, making it a target for commercial fisheries.
Atlantic Bluefin Tuna (Thunnus thynnus) moved from Endangered to Least Concern in 2021, reflecting a 22% population increase over four decades. This recovery is attributed to stricter fishing quotas and efforts to combat illegal fishing. However, historical overfishing led to significant population drops, with some estimates indicating an 80-90% reduction over 80 years. Pacific Bluefin Tuna is currently listed as Near Threatened with decreasing numbers.
Bigeye Tuna (Thunnus obesus) remains classified as Vulnerable on the IUCN Red List. Highly valued for sashimi, it faces intense fishing pressure. Overfishing has occurred in the Eastern and Western Pacific, and Indian Oceans. Juvenile Bigeye Tuna are often caught as bycatch in Skipjack Tuna fisheries, further impacting their populations.
Skipjack Tuna (Katsuwonus pelamis) is generally considered Least Concern. It is the most heavily fished tuna, accounting for at least 60% of the global catch, but is fast-growing and reproduces at a young age. Albacore Tuna (Thunnus alalunga) also moved from Near Threatened to Least Concern in 2021. While some regional stocks, like those in the northern and southern Atlantic, have been overfished, the overall population is stable. Overfishing and illegal, unreported, and unregulated (IUU) fishing practices continue to threaten various tuna species.
Protecting Tuna Populations
International fishing regulations and quotas play a significant role in tuna conservation. Organizations like the International Commission for the Conservation of Atlantic Tunas (ICCAT) establish total allowable catches (TACs) to manage fishing pressure. For example, ICCAT maintained 2023 TACs for Eastern Atlantic Bluefin Tuna, Mediterranean Albacore, and Bigeye Tuna for 2024. Regulations also include measures to reduce fishing mortality of juvenile Bigeye and Yellowfin Tuna, such as limiting fish aggregating devices (FADs) and implementing closure periods.
Sustainable fishing practices minimize impacts on tuna populations and marine ecosystems. Methods like pole-and-line fishing and trolling are more selective, reducing bycatch. Pole-and-line fishing catches tuna one-by-one, often targeting younger, migratory tuna. Trolling uses artificial lures towed behind a boat, a selective method particularly for Albacore Tuna.
Consumer choices contribute to conservation efforts. Eco-labels like the Marine Stewardship Council (MSC) certification guide individuals toward sustainably sourced tuna. The MSC blue fish label indicates seafood from a well-managed, environmentally sustainable fishery. Consulting seafood guides helps consumers make informed decisions, supporting fisheries that prioritize long-term ocean health. Habitat protection, such as marine protected areas (MPAs), provides safe havens for tuna to breed, feed, and grow, contributing to their recovery and long-term viability.