Animal Diversity Web

Ge­o­graphic Range

Al­ba­core re­side in the sub­trop­i­cal re­gions of the North Pa­cific Ocean, In­dian Ocean, North At­lantic Ocean, and Mediter­ranean Sea. In the North Pa­cific, al­ba­core are dis­trib­uted through­out a re­gion from 10 to 50 de­grees north lat­i­tude, with mi­gra­tion to­wards the trop­i­cal wa­ters dur­ing spring and sum­mer spawn­ing months. Al­ba­core oc­cupy sim­i­lar lat­i­tudes in the At­lantic Ocean, but young al­ba­core have been caught by fish­er­men be­tween 40 to 50 de­grees north lat­i­tude. In the In­dian Ocean, al­ba­core are dis­trib­uted through­out a re­gion from 50 de­grees north lat­i­tude to 40 de­grees south lat­i­tude. In the north, im­ma­ture al­ba­core oc­cupy 25 to 35 de­grees north lat­i­tude, ma­ture al­ba­core oc­cupy the north equa­to­r­ial cur­rent re­gion, and spawn­ing al­ba­core oc­cupy the area near 20 de­grees north lat­i­tude. To the south, ma­ture al­ba­core oc­cupy an area north of 10 de­grees south lat­i­tude, im­ma­ture al­ba­core oc­cupy the area south of 30 de­grees south lat­i­tude, and spawn­ing al­ba­core oc­cupy the area in be­tween (10 to 30 de­grees south lat­i­tude). Note that for these mi­gra­tory tuna, April to Sep­tem­ber are the non-spawn­ing months and Oc­to­ber to March are the spawn­ing months in the In­dian Ocean, while in the At­lantic, April to Sep­tem­ber are the spawn­ing months. (Bard, 2001; Chen, et al., 2005; Watan­abe, et al., 2004)

• Biogeographic Regions
• indian ocean
  • native
• atlantic ocean
  • native
• pacific ocean
  • native
• mediterranean sea
  • native

Habi­tat

Al­ba­core have been found in­hab­it­ing depths of 0 to 600 m. Large al­ba­core (~21 kg) typ­i­cally oc­cupy depths from 0 to 450 m, with a max­i­mum abun­dance be­tween 250 and 300 m. This 250 to 300 m depth has a water tem­per­a­ture of 25 to 15 de­grees Cel­sius. While larger-bod­ied al­ba­core tend to be ac­tive around cooler areas (some ven­ture into deeper water rang­ing from 10 to 25 de­grees Cel­sius), smaller-bod­ied al­ba­core tend to oc­cupy warmer lay­ers. Being pelagic, they have no de­pen­dence on the sea floor. (Bard, 2001; Col­lette and Nauen, 1983)

• Habitat Regions
• saltwater or marine

• Aquatic Biomes
• pelagic

• Range depth

  0 to 600 m

  0.00 to 1968.50 ft

Phys­i­cal De­scrip­tion

Al­ba­core typ­i­cally reach sex­ual ma­tu­rity at a length of 90 cm. The max­i­mum recorded size is 140 cm and 60.3 kg. Weight varies con­sid­er­ably within the species, with im­ma­ture al­ba­core weigh­ing less than 14 kg and ma­ture al­ba­core weigh­ing more than 14 kg. One of the most dis­tin­guish­able traits of al­ba­core are the ex­tremely long pec­toral fins. In in­di­vid­u­als longer than 50 cm, the pec­toral fin can be 30% of the fork length. Be­cause the closely re­lated big­eye tuna (Thun­nus obe­sus) also have ex­tremely long pec­toral fins, al­ba­core are often con­fused with ju­ve­nile big­eye tuna. Pec­toral fins of big­eye tuna have rounded tips while pec­toral fins of al­ba­core have more pointed tips. Be­cause big­eye tuna grow much larger than al­ba­core, only ju­ve­nile big­eye tuna are misiden­ti­fied as al­ba­core. In ad­di­tion to long pec­toral fins, al­ba­core have very small scales cov­er­ing their body, 11 to 14 dor­sal spines, 12 to 16 dor­sal soft rays, 11 to 16 anal soft rays, and no anal spines. Be­cause the an­te­rior spines are longer than the pos­te­rior spines in the dor­sal fin, the dor­sal fin ap­pears to have a con­cave out­line point­ing back to­ward the tail. Al­ba­core have a faint blue iri­des­cent band along the side of the body as well as yel­low shades in the dor­sal and anal fins. Males are sim­i­lar to fe­males in ap­pear­ance and color, but begin to grow larger in size after sex­ual ma­tu­rity due to dif­fer­ent growth rates. (Chen, et al., 2005; Col­lette and Nauen, 1983)

• Other Physical Features
• ectothermic
• bilateral symmetry

• Sexual Dimorphism
• male larger

• Range mass

  60.3 (high) kg

  132.82 (high) lb

• Range length

  140 (high) cm

  55.12 (high) in

De­vel­op­ment

Al­though al­ba­core are closely re­lated and quite sim­i­lar to skip­jack tuna and yel­lowfin tuna, they have dif­fer­ent life his­tory strate­gies. Skip­jack tuna and yel­lowfin tuna are char­ac­ter­ized by rapid growth and de­vel­op­ment, early mat­u­ra­tion, and high en­ergy input into gonad pro­duc­tion. Al­ba­core on the other hand, grow slow, ma­ture late, and put rel­a­tively lit­tle en­ergy into gonad pro­duc­tion. The life stages of al­ba­core in­clude im­ma­ture ju­ve­niles, non-spawn­ing ma­ture adults, and spawn­ing ma­ture adults. The eggs and lar­vae are plank­tonic, float­ing around the water col­umn freely. The typ­i­cal age of sex­ual ma­tu­rity is five years. Up until the age of four, dif­fer­ences be­tween males and fe­males are neg­li­gi­ble, but after that, males be­come in­creas­ingly larger than fe­males. When cap­tured, sex is de­ter­mined by gonad analy­sis. (Es­s­ing­ton, 2003; San­ti­ago and Ar­riz­a­bal­aga, 2005)

Re­pro­duc­tion

Al­ba­core are polyg­y­nan­drous. They spawn as a group by sim­ply re­leas­ing their eggs and sperm into the water. (Col­lette and Nauen, 1983)

• Mating System
• polygynandrous (promiscuous)

Al­ba­core are an iteroparous species that breed sea­son­ally. Adults make a spawn­ing mi­gra­tion to­ward more trop­i­cal wa­ters dur­ing the sum­mer months (April to Sep­tem­ber in the North­ern Hemi­sphere, Oc­to­ber to March in the South­ern Hemi­sphere). Fe­males lay eggs that are fer­til­ized ex­ter­nally (oviparous). Al­ba­core tend to scat­ter their eggs through­out the ocean. A 20 kg fe­male can pro­duce 2 to 3 mil­lion eggs in two batches. How­ever, this varies by size. Al­ba­core reach sex­ual ma­tu­rity at about five years of age. (Col­lette and Nauen, 1983; San­ti­ago and Ar­riz­a­bal­aga, 2005)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• fertilization
  • external
• broadcast (group) spawning
• oviparous

• Breeding interval

  Albacore breed once yearly

• Breeding season

  Albacore breed July to September in the Northern Hemisphere, October to March in the Southern Hemisphere

• Average number of offspring

  2 million

• Average age at sexual or reproductive maturity (female)

  5 years

• Average age at sexual or reproductive maturity (male)

  5 years

Be­sides the con­tri­bu­tion of their ga­metes and the en­ergy ex­pended mi­grat­ing to spawn­ing grounds, there is no parental in­vest­ment by al­ba­core. (Col­lette and Nauen, 1983)

• Parental Investment
• no parental involvement

Lifes­pan/Longevity

Males grow larger and to a later age in the At­lantic and Mediter­ranean. Max­i­mum lifes­pan of al­ba­core in the At­lantic is 13 years, while it is only 9 years in the Mediter­ranean. Be­fore sex­ual ma­tu­rity, the pop­u­la­tion sex ratio is 1:1. After ma­tu­rity, males pre­dom­i­nate due to dif­fer­ences in mor­tal­ity and growth rate. (Col­lette and Nauen, 1983; Megalo­fo­nou, 2000)

• Range lifespan
  Status: wild

  13 (high) years

Be­hav­ior

Al­ba­core tuna are highly mi­gra­tory and move with cur­rent sys­tems dur­ing sea­sonal water move­ments. Al­ba­core travel in large schools of mixed species that in­clude skip­jack tuna, yel­lowfin tuna and bluefin tuna. These schools are usu­ally formed around float­ing ob­jects such as sar­gas­sum weeds. (Chen, et al., 2005; Col­lette and Nauen, 1983; Watan­abe, et al., 2004)

• Key Behaviors
• natatorial
• motile
• migratory
• social

Com­mu­ni­ca­tion and Per­cep­tion

Lit­tle spe­cific in­for­ma­tion is avail­able on how al­ba­core per­ceive their en­vi­ron­ment or com­mu­ni­cate with oth­ers. How­ever, they most likely per­ceive their en­vi­ron­ment through vi­sual, au­di­tory, tac­tile, and chem­i­cal means, as do most fish. (Von der Emde, et al., 2004)

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

The pri­mary diet of al­ba­core in­cludes pa­cific saury, north­ern an­chovy, crus­tacean zoo­plank­ton, go­natid squid, and Japan­ese an­chovy. Al­ba­core are op­por­tunis­tic pis­ci­vores and their diet varies sea­son­ally de­pend­ing on lo­ca­tion. An­chovy typ­i­cally con­sti­tutes up to 96% of the stom­ach con­tents of al­ba­core at any given time. Some stud­ied fish fed on other schools of fish when en­coun­tered due to the patchy dis­tri­b­u­tion of an­chovy, demon­strat­ing the op­por­tunis­tic feed­ing habits of al­ba­core. Al­ba­core also ex­hibit a diel ver­ti­cal mi­gra­tion pat­tern, fol­low­ing their prey through­out the water col­umn. (Bernard, et al., 1985; Watan­abe, et al., 2004)

• Primary Diet
• carnivore
  • piscivore

• Animal Foods
• fish
• mollusks
• aquatic crustaceans
• zooplankton

• Plant Foods
• phytoplankton

Pre­da­tion

Many sharks, rays, larger tunas, and bill­fishes are preda­tors that prey upon al­ba­core. Be­cause al­ba­core are valu­able com­mer­cial fish, hu­mans are also im­por­tant preda­tors. (Col­lette and Nauen, 1983; Es­s­ing­ton, 2003)

• Known Predators

  • sharks and rays (Chondrichthyes)
  • larger tunas (Scombridae)
  • billfishes (Istiophoridae)
  • humans (Homo sapiens)

Ecosys­tem Roles

Al­ba­core fall into the fourth trophic level in the oceanic ecosys­tem. Al­ba­core are top preda­tors that prey upon many aquatic species. (Watan­abe, et al., 2004)

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Al­ba­core are im­por­tant com­mer­cially and are highly tar­geted by fish­eries around the world, es­pe­cially by Tai­wan, Japan, and Korea. They are caught and sold fresh, frozen, or canned. (Chen, et al., 2005; Col­lette and Nauen, 1983)

• Positive Impacts
• food

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

Cur­rent re­search is be­gin­ning to show that some tuna con­sumed by hu­mans may ex­ceed the Food and Drug Ad­min­is­tra­tion's orig­i­nal ac­tion level of 0.5 ppm mer­cury. Tuna mar­keted in stores as white tuna, such as al­ba­core, con­tains twice as much mer­cury as skip­jack tuna, which is typ­i­cally mar­keted as light or chunk light tuna. This is not a major health issue right now, but it may be wise to per­form fur­ther re­search on this in­or­ganic metal con­t­a­m­i­nant in tuna. (Burger and Gochfeld, 2004)

Con­ser­va­tion Sta­tus

As a whole, al­ba­core are not cited as en­dan­gered by any major or­ga­ni­za­tions, but not enough in­for­ma­tion is avail­able for a de­fin­i­tive clas­si­fi­ca­tion. This is due to lack of fish­ing for al­ba­core past cer­tain depths. How­ever, the north At­lantic stock of al­ba­core is listed as vul­ner­a­ble by the IUCN, and the south At­lantic stock is listed as crit­i­cally en­dan­gered. (Bard, 2001; Uozumi, 2004)

• IUCN Red List

  Critically Endangered
  More information

• IUCN Red List

  Critically Endangered
  More information

• US Federal List

  No special status

• CITES

  No special status

Con­trib­u­tors

Al­li­son Poor (ed­i­tor), Uni­ver­sity of Michi­gan-Ann Arbor.

Michael Hwang (au­thor), Uni­ver­sity of Michi­gan-Ann Arbor, Kevin Wehrly (ed­i­tor, in­struc­tor), Uni­ver­sity of Michi­gan-Ann Arbor.

Ref­er­ences

Bard, F. 2001. Ex­ten­sion of Ge­o­graph­i­cal and Ver­ti­cal Habi­tat of Al­ba­core (Thun­nus alalunga) in the North At­lantic Pos­si­ble Con­se­quences on True Rate of Ex­ploita­tion of this Stock. ICCAT, 52/4: 1447-1456.

Bernard, H., J. Hedgepeth, S. Reilly. 1985. Stom­ach Con­tents of Al­ba­core, Skip­jack, and Bonito Caught Off South­ern Cal­i­for­nia Dur­ing Sum­mer 1983. Ca­COFL Rep, 26: 175-183.

Burger, J., M. Gochfeld. 2004. Mer­cury in canned tuna: white ver­sus light and tem­po­ral vari­a­tion. En­vi­ron­men­tal Re­search, 96: 239-259.

Chen, I., P. Lee, W. Tzeng. 2005. Dis­tri­b­u­tion of al­ba­core (Thun­nus al­ba­core) in the In­dian Ocean and its re­la­tion to en­vi­ron­men­tal fac­tors. Fish­eries Oceanog­ra­phy, 14/1: 70-80.

Col­lette, B., C. Nauen. 1983. Scom­brids of the world. An an­no­tated and il­lus­trated cat­a­logue of tunas, mack­erels, boni­tos and re­lated species known to date. FAO species cat­a­logue, 2: 137.

Es­s­ing­ton, T. 2003. De­vel­op­ment and Sen­si­tiv­ity Analy­sis of Bioen­er­get­ics Mod­els for Skip­jack Tuna and Al­ba­core: A Com­par­i­son of Al­ter­na­tive Life His­to­ries. Trans­ac­tions of the Amer­i­can Fish­eries So­ci­ety, 132: 759-770.

Megalo­fo­nou, P. 2000. Age and growth of Mediter­ranean al­ba­core. Jour­nal of Fish Bi­ol­ogy, 57: 700-715.

San­ti­ago, J., H. Ar­riz­a­bal­aga. 2005. An in­te­grated growth study for North At­lantic al­ba­core (Thun­nus alalunga Bonn. 1788). Jour­nal of Ma­rine Sci­ence, 62: 740-749.

Uozumi, Y. 2004. "Thun­nus alalunga" (On-line). 2004 IUCN Red List of Threat­ened Species. Ac­cessed De­cem­ber 16, 2005 at www.​redlist.​org.

Von der Emde, G., J. Mog­dans, B. Kapoor. 2004. The senses of fish : adap­ta­tions for the re­cep­tion of nat­ural stim­uli. Boston: Kluwer.

Watan­abe, H., T. Ku­bodera, S. Ma­suda, S. Kawa­hara. 2004. Feed­ing habits of al­ba­core Thun­nus alalunga in the tran­si­tion re­gion of the cen­tral North Pa­cific. Fish­eries Sci­ence, 70: 573-579.