Animal Diversity Web

Ge­o­graphic Range

The White Stur­geon is found on the Pa­cific slope of North Amer­ica from the Aleut­ian Is­lands, AK to Baja, CA. It is anadro­mous fish, spend­ing most of its life in sea near the shore and can be found in es­tu­ar­ies of large rivers. It mi­grates far in­land in large rivers to spawn. (Kee, et. al. 1981; Boschung, 1985).

• Biogeographic Regions
• nearctic
  • native

Habi­tat

His­tor­i­cally, white stur­geon spent their life in sev­eral habi­tats; streams, rivers, es­tu­ar­ies, and ma­rine wa­ters. They are anadro­mous fish but may spend much or all of their lives in fresh water if they can­not reach the sea (Hart 1973). White stur­geon his­tor­i­cally oc­curred on the Pa­cific Coast, re­pro­duc­ing in at least three large river sys­tems, in­clud­ing Sacra­mento-San Joaquin River in Cal­i­for­nia, the Co­lum­bia River basin in the Pa­cific North­west, and the Fraser River sys­tem in British Co­lum­bia (Fish and Wildlife Ser­vice, In­te­rior, 1994). The build­ing of dams along the rivers has im­pacted the pop­u­la­tions of white stur­geons by cre­at­ing land­locked pop­u­la­tions and de­stroy­ing spawn­ing grounds.

White stur­geon are still dis­trib­uted through­out the river sys­tems of the Pa­cific north­west, but these pop­u­la­tions are iso­lated and their mi­gra­tion is lim­ited within the se­ries of pools and lakes that make up these new dammed rivers (Pa­cific States Ma­rine Fish­eries Com­mis­sion, 2000)

• Aquatic Biomes
• rivers and streams
• coastal

Phys­i­cal De­scrip­tion

There are sev­eral dis­tin­guish­ing char­ac­ter­is­tics of the white stur­geon. Its body is elon­gate and cylin­dri­cal and can be large, with sizes as large as 3.8 to 6 me­ters and weights as high as 630 kg.

It has no scales but five rows of "scutes" along the body. There are 11-14 plates in front of the sin­gle dor­sal fin, 38-48 plates from the head along the cen­tral cau­dal axis, and 9-12 from the head to the pelvic fins. Dor­sal color is light gray while the ven­tral sur­face is white.

The mouth is ven­tral, mod­er­ate in size and di­rected down­ward. The white stur­geon has no teeth, in­stead using its 'vac­uum cleaner' like mouth that is ca­pa­ble of si­phon­ing up food. This fish is rec­og­nized by its short broad snout with four bar­bels closer to the tip of the snout than the mouth. (Hart, 1973; Pa­cific States Ma­rine Fish­eries Com­mis­sion 1996).

• Other Physical Features
• ectothermic
• heterothermic
• bilateral symmetry

• Sexual Dimorphism
• sexes alike

• Range mass

  630 (high) kg

  1387.67 (high) lb

Re­pro­duc­tion

The exact re­pro­duc­tive win­dow for white stur­geon is not known, how­ever for stur­geons in gen­eral the males re­pro­duce for 10 to 20 years and fe­males for 15 to 25 years. The size or age of ma­tu­rity is vari­able, and spawn­ing oc­curs when the phys­i­cal en­vi­ron­ment per­mits vitel­lo­ge­n­e­sis (egg de­vel­op­ment) and cues ovu­la­tion. Land­locked stur­geons have been ob­served to spawn dur­ing pe­ri­ods of peak river flow with high water ve­loc­i­ties that dis­perse and pre­vent clump­ing of the eggs. White stur­geon are broad­cast spawn­ers be­cause they re­lease their eggs and sperm in fast water. In­for­ma­tion from Fish and Wildlife Ser­vice (1994)

• Average age at sexual or reproductive maturity (female)
  Sex: female

  8212 days

  AnAge

• Average age at sexual or reproductive maturity (male)
  Sex: male

  6022 days

  AnAge

Lifes­pan/Longevity

• Average lifespan
  Status: wild

  100.0 years

  Max Planck Institute for Demographic Research

• Average lifespan
  Status: wild

  80.0 years

  Max Planck Institute for Demographic Research

• Average lifespan
  Status: wild

  82.0 years

  Max Planck Institute for Demographic Research

Be­hav­ior

White stur­geon are slow grow­ing, late ma­tur­ing, anadro­mous fish.

Adults spend most of their time in sea near the shore, but they have been found in depths of 30 me­ters. Adults move into large rivers in early spring and spawn by May or June. They can as­cend far in­land to spawn (Lee 1980). Land­locked fish also mi­grate. Tag­ging stud­ies of Kootemai river white stur­geon re­vealed that in spring, the fish were ob­served to have moved up­river 16 to 114 river kilo­me­ters, and re­mained con­gre­gated in spe­cific lo­ca­tions through the sum­mer. The fish that were seden­tary dur­ing the sum­mer in­hab­ited the deep­est holes of the river (Fish and Wildlife Ser­vice 1994).

• Key Behaviors
• natatorial
• motile

Com­mu­ni­ca­tion and Per­cep­tion

• Perception Channels
• tactile
• chemical

Food Habits

White Stur­geon have been de­scribed as op­por­tunis­tic feed­ers, feed­ing on the bot­tom with their long snouts and using their bar­bels to de­tect food. When small they feed on clams, mus­sels, cray­fish, worms, and fish eggs. At a larger size, they prey on fish such as smelt, an­chovies, lam­prey, shad and salmon.

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

The size com­bined with the "char­ac­ter­is­tic qual­ity of its flesh" makes it a valu­able game fish in areas were it is not pro­tected. Its roe can be used for caviar, and Co­lum­bia river roe pro­duc­tion is "sec­ond only to the for­mer So­viet Union" (Hart 1973; Pa­cific States Ma­rine Fish­eries Com­mis­sion 1996).

Con­ser­va­tion Sta­tus

In 1994, the pop­u­la­tion of White Stur­geon lo­cated in the Koote­nai river was granted en­dan­gered sta­tus. The pop­u­la­tion has been de­clin­ing since the 1960's and there has been a com­plete lack of re­cruit­ment of breed­ing ju­ve­niles in the pop­u­la­tion since 1974. The de­cline cor­re­sponds to the open­ing of the Libby Dam in Mon­tana and pos­si­bly from poor water qual­ity and the ef­fects of con­t­a­m­i­nants (Fish and Wildlife Ser­vice 1994).

Joint ef­forts be­tween Canada and the United States are un­der­way to ad­dress the needs of the Koote­nai pop­u­la­tion by de­vel­op­ing a re­gional re­cov­ery strat­egy (Duke, 2000).

• IUCN Red List

  Critically Endangered
  More information

• IUCN Red List

  Critically Endangered
  More information

• US Federal List

  Endangered

Other Com­ments

White Stur­geons are the largest fresh­wa­ter fish in North Amer­ica. The largest white stur­geon was taken from the Snake River in Idaho in 1898 and it weighed 682 kilo­grams (Duke 2000).

The name comes from "acipenser," an Old World name mean­ing stur­geon and trans­mon­tan­ta­nus mean­ing be­yond the moun­tains. This seems fit­ting for a fish found west in the New World (Pa­cific States Ma­rine Fish­eries Com­mis­sion 1996).

Con­trib­u­tors

William Fink (ed­i­tor), Uni­ver­sity of Michi­gan-Ann Arbor.

Charles Der­shimer (au­thor), Uni­ver­sity of Michi­gan-Ann Arbor.

Ref­er­ences

Boschung, H. 1985. The Audubon So­ci­ety Field Guide to North Amer­i­can Fishes, Whales, and Dol­phins. New York: AAl­fred A. Knopf, Inc..

Duke, S. March 3, 2000. "The Koote­nai River Pop­u­la­tion of White Stur­geon" (On-line). Ac­cessed Sun­day, Oc­to­ber 22, 2000 at http://​endangered.​fws.​gov/​features/​sturgeon/​.

Fish and Wildlife Ser­vice, In­te­rior, Sep­tem­ber 6, 1994. "En­dan­gered and Threat­ened Wildlife and Plants; De­ter­mini­a­tion of En­dan­gered Sta­tus for the Koote­nai River Pop­u­la­tion of the White Stur­geon" (On-line). Ac­cessed Oc­to­ber 22, 2000 at http://​endangered.​fws.​gov/​r/​fr94549.​html.

Hart, J. 1973. Pa­cific Fishes of Canada.. Ot­tawa: Fish­eries Re­search Board of Canada.

Kee, S. 1981. Atlas of North Amer­i­can Fresh­wa­ter Fishes. North Car­olina: North Car­olina State Mu­seum of Nat­ural His­tory.

Pa­cific States Ma­rine Fish­eries Com­mis­sion, De­cem­ber 16, 1996. "White Stur­geon" (On-line). Ac­cessed Oc­to­ber 24, 2000 at http://​www.​psmfc.​org/​habitat/​edu_​wsturg_​fact.​html.