Albacore tuna (Thunnus alalunga)

Also known as: aáhi taria, albacore, albacore fish, bastard albacore, bonito, Langvin tuna, longfin tuna, longfin tunny, long-fin tunny, long-finned tuna, tuna
Synonyms: Germo germon, Orcynus pacificus, Scomber alalunga, Scomber alatunga, Scomber albicans, Scomber germo, Scomber germon, Thunnus germo, Thunnus pacificus, Thynnus alalonga, Thynnus alalunga, Thynnus pacificus
  
French: Ara Lunga, Bonette, Germon, Germon Atlantique
Spanish: Alalunga, Atún, Atún Aleta Larga, Atún Blanco, Atún de Aleta Larga, Bonito del Norte, Sierra
KingdomAnimalia
PhylumChordata
ClassActinopterygii
OrderPerciformes
FamilyScombridae
GenusThunnus (1)
Weightup to 40 kg (2)

The albacore tuna is classified as Near Threatened (NT) on the IUCN Red List (1).

The large, oceanic albacore tuna (Thunnus alalunga) is built for speed, with a torpedo-shaped body, smooth skin and streamlined fins (3). This fish is characterized by a dark yellow first dorsal fin and a pale yellow second dorsal fin (4). The pectoral fins, found on each side of the body, are exceptionally long, and the crescent-shaped, deeply-forked tail fin helps generate the power required to maintain the albacore tuna’s impressive speeds. The albacore tuna is metallic dark blue on the back, with silvery-white sides and belly (3).

Occurs in tropical and temperate waters of all oceans, including the Mediterranean Sea, from 50°N to 40°S. The Atlantic and Pacific Oceans both hold at least two albacore tuna stocks (northern and southern), each with distinct spawning areas and rarely crossing the warm equatorial waters (2).

An epipelagic and mesopelagic, oceanic species, found in waters of 13.5° to 25.2°C. The albacore tuna may tolerate temperatures as low as 9.5°C for short periods (2).

The albacore tuna forms schools, which can be up to an astonishing 30 kilometres wide (3). These enormous schools are sometimes associated with floating objects, such as sargassum weeds, and they may also form mixed schools with other tuna species, such as skipjack, yellowfin and bluefin tuna (2). In these schools, the albacore tuna undertakes great migrations in search of the best feeding and spawning grounds, strongly influenced by large oceanic phenomena such as El Niño (5) (6). Albacore tuna are able to reach impressive speeds, of up to 80 kilometres per hour, due to their highly evolved circulatory system that reduces the loss of heat generated by increased muscular activity. This allows them to maintain their body temperature at a higher level than the surrounding water, keeping their muscles warm and working efficiently (3). Unlike many fish, albacore tuna are not able to pump water over their gills to obtain oxygen from the surrounding water, and therefore need to swim constantly with their mouth open, to force water over their gills. A high volume and pressure of blood, and great haemoglobin concentration, all increases the ability of the fish to absorb the essential oxygen (3).

Albacore tuna are believed to be pelagic spawners, meaning that the female releases her eggs, and the male his sperm, into open water, often near the water’s surface (3). A female albacore tuna is capable of producing two to three million eggs per spawning season, which are released in at least two batches (2); however, the majority of these eggs will not survive to be adults (3). The tiny eggs are just one millimetre in diameter and are enclosed in an oil droplet to enable them to remain buoyant in the ocean. The eggs are fertilized by the male, and the resulting fertilized eggs develop rapidly, with hatching occurring in less than 48 hours (3).

The large albacore tuna is one of the top carnivores within the ocean regions it inhabits, and it preys voraciously upon smaller schooling fish such as sardines and anchovy, and squid, consuming around 25 percent of its weight every day. The albacore tuna itself becomes prey for larger species of tuna, billfish and sharks (3).

For many years, important fisheries have existed for the albacore tuna in the Atlantic and Pacific Oceans. As efforts to catch fish have increased, the world catch of albacore tuna has been gradually declining and many stocks are now over-fished, or fully exploited and nearing a situation of over-fishing (2) (5). The North Atlantic stock has declined to about one quarter of the peak levels estimated for the 1940s, and likewise, the South Atlantic stock has been reduced by fisheries to about 25 percent of its un-fished level (7). While there are regulations regarding the amount of albacore tuna that can be caught in many areas, enforcing such fishing laws can be challenging as the boats operate on the high seas far from observation (8).

In the Atlantic Ocean, the International Commission for the Conservation of Atlantic Tunas (ICCAT) is responsible for the conservation of the albacore tuna. Based on scientific evidence, the Commission can adopt recommendations and resolutions aimed at maintaining populations of tuna species at levels which will permit maximum sustainable catch (7). An assessment of albacore tuna stocks undertaken in 2007 led to the recommendation that the total allowable catch should be reduced for the North Atlantic stock if it is to recover from its over-fished condition. Even though the South Atlantic stock was also found to be over-fished, the Commission considered that the current management regulations for the South Atlantic stock are sufficient for its recovery (7). Similarly, the Inter-American Tropical Tuna Commission (IATTC) is responsible for the conservation and management of fisheries for tunas in the eastern Pacific Ocean (9).This species has also been classified as a highly migratory species in Annex I of the Convention on the Law of the Sea, meaning that nations should cooperate in its conservation (10).

The albacore tuna was reclassified from Data Deficient (DD) to Near Threatened (NT) in 2011, as although implemented catch quotas have reduced population declines, further reductions in population size have been predicted in certain parts of its range (1).

For more information on the albacore tuna:

For up-to-date information on the status of albacore tuna stocks in the Atlantic:

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

  1. IUCN Red List (December, 2011)
    http://www.iucnredlist.org/
  2. Collette, B.B. and Nauen, C.E. (1983) FAO Species Catalogue. Vol. 2: Scombrids of the World. An annotated and illustrated catalogue of tunas, mackerels, bonitos and related species known to date. Food and Agriculture Organization of the United Nations, Rome.
  3. Southwest Fisheries Science Center: Albacore Research (December, 2011)
    http://swfsc.noaa.gov/textblock.aspx?Division=FRD&id=1168&ParentMenuId=139
  4. NSW Department of Primary Industries (December, 2011)
    http://www.dpi.nsw.gov.au/fisheries/recreational/saltwater/sw-species/albacore
  5. Atuna: Tuna Species Guide (December, 2011)
    http://www.atuna.com/
  6. Kimura, S., Nakai, M. and Sugimoto, T. (1997) Migration of albacore, Thunnus alalunga, in the North Pacific Ocean in relation to large oceanic phenomena. Fisheries Oceanography, 6(2): 51 - 57.
  7. ICCAT (December, 2011)
    http://www.iccat.int
  8. SeaChoice (December, 2011) 
    http://www.seachoice.org/profile/70/view
  9. IATTC (December, 2011)
    http://www.iattc.org/
  10. Convention on the Law of the Sea (January, 2012)
    http://www.un.org/depts/los/convention_agreements/convention_overview_convention.htm