Thaleichthys pacificus  (Richardson, 1836)

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Native range | All suitable habitat | Year 2100
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Thaleichthys pacificus   AquaMaps   Data sources: GBIF OBIS
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Image of Thaleichthys pacificus (Eulachon)
Thaleichthys pacificus
Picture by Bull. U.S. Bur. Fish.

Classification / Names Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa

Actinopterygii (ray-finned fishes) > Osmeriformes (Smelts) > Osmeridae (Smelts)
Etymology: Thaleichthys: Greek, thaleia, -as = abundance + Greek, ichthys = fish (Ref. 45335);  pacificus: pacificus - of the Pacific (Ref. 1998).

Environment / Climate / Range Ecology

Marine; freshwater; brackish; pelagic-neritic; anadromous (Ref. 51243); depth range 0 - 300 m (Ref. 6793).   Temperate; 61°N - 36°N

Length at first maturity / Size / Weight / Age

Maturity: Lm ?, range 15 - 16 cm
Max length : 34.0 cm TL male/unsexed; (Ref. 56527); common length : 20.0 cm TL male/unsexed; (Ref. 7354); max. reported age: 5 years (Ref. 12193)

Short description Morphology | Morphometrics

Dorsal spines (total): 0; Dorsal soft rays (total): 10-13; Anal spines: 0; Anal soft rays: 18 - 23; Vertebrae: 65 - 72. Distinguished by the large canine teeth on the vomer and 18 to 23 rays in the anal fin (Ref. 27547). Adipose fin sickle-shaped; paired fins longer in males than in females; all fins with well developed breeding tubercles in ripe males which are poorly developed or absent in females (Ref. 27547). Adult coloration is brown to blue on back and top of the head, the sides lighter to silvery white, and the ventral surface white; speckling is fine, sparse and restricted to the back; peritoneum is light with black speckles (Ref. 6885). Fins transparent, pectorals and caudal often dusky (Ref. 27547). During spawning, male fish has a distinctly raised ridge along the middle of the body and a rough texture, differentiating it from the female which is smaller, smoother and shinier.

Distribution Countries | FAO areas | Ecosystems | Occurrences | Point map | Introductions | Faunafri

North Pacific: west of Saint Matthew Island and Kuskokwim Bay in the Bering Sea, and Bowers Bank in the Aleutian Islands to Monterey Bay, California, USA. Populations from northern British Columbia are separate from those in the Fraser River (Ref. 10276).

Biology     Glossary (e.g. epibenthic)

Found near shore and in coastal inlets and rivers (Ref. 2850). Possibly to 625 m depth (Ref. 6793). Spends most of its life in the sea, returning to freshwater streams to spawn (Ref. 27547). There is evidence of return to natal streams (Ref. 10276). May migrate up to 160 km upstream. Feeds on plankton and only while at sea (11699, 10276). Excellent food fish and source of oil (15% body wt.). Anadromous (Ref. 96339).

Life cycle and mating behavior Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae

The spawning run from the sea to freshwater streams begins when river temperature rises to about 4.4° but the fish stop running if temperature exceeds 7.8°C. Males predominate the early part of the run, but their numbers are equalled or exceeded by females later (Ref. 10276, 11699). Adults usually die after spawning but some move back to the sea and return to spawn a second time (Ref. 1998). Upon hatching, larvae are found near the bottom and are soon carried downstream to salt water and eventually found in the scattering layer of coastal waters (Ref. 27547).

Main reference Upload your references | References | Coordinator | Collaborators

Eschmeyer, W.N., E.S. Herald and H. Hammann, 1983. A field guide to Pacific coast fishes of North America. Houghton Mifflin Company, Boston, U.S.A. 336 p. (Ref. 2850)

IUCN Red List Status (Ref. 96402)

CITES (Ref. 94142)

Not Evaluated

Threat to humans


Human uses

Fisheries: commercial
FAO(fisheries: production; publication : search) | FisheriesWiki | Sea Around Us

More information

FAO areas
Food items
Food consumption
Larval dynamics
Aquaculture profile
Allele frequencies
Mass conversion
Stamps, Coins
Swim. type
Gill area


Special reports

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Internet sources

BHL | Cloffa | BOLDSystems | Websites from users | Check FishWatcher | CISTI | Catalog of Fishes (gen., sp.) | DiscoverLife | Faunafri | Fishtrace | GenBank(genome, nucleotide) | GOBASE | Google Books | Google Scholar | Google | IGFA World Record | iSpecies | PubMed | Scirus | SeaLifeBase | Tree of Life | uBio | Wikipedia(Go, Search) | World Records Freshwater Fishing | Zoological Record

Estimates of some properties based on models

Phylogenetic diversity index (Ref. 82805):  PD50 = 1.0000   [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00417 (0.00189 - 0.00918), b=3.12 (2.92 - 3.32), based on LWR estimates for this (Sub)family-body shape (Ref. 93245).
Trophic Level (Ref. 69278):  3.3   ±0.37 se; Based on food items.
Resilience (Ref. 69278):  Medium, minimum population doubling time 1.4 - 4.4 years (tm=2-6; tmax=5; K=0.34; Fec=17,000-60,000 Musick et al. 2000 (Ref. 36717)).
Vulnerability (Ref. 59153):  Low to moderate vulnerability (33 of 100) .
Price category (Ref. 80766):   Very high.