Eulachon

{{Short description|Species of fish}} {{hatnote|"Candlefish" redirects here. In British English, "Candlefish" refers to the Sablefish.}} {{Speciesbox | image = Eulachon.jpg |status=LC |status_system=IUCN3.1 |status_ref=<ref name=iucn>{{cite IUCN|author=NatureServe|year=2013|title=''Thaleichthys pacificus''|article-number=e.T202415A18236183|doi=10.2305/IUCN.UK.2013-1.RLTS.T202415A18236183.en|access-date=7 May 2023}}</ref> |status2=G5 |status2_system=TNC |status2_ref=<ref name=ns>{{cite web|url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.100935/Thaleichthys_pacificus|title=''Thaleichthys pacificus''|publisher=NatureServe|location=Arlington, Virginia|author=NatureServe|website=NatureServe Network Biodiversity Location Data accessed through NatureServe Explorer|access-date=7 May 2023|date=5 May 2023}}</ref> | parent_authority = Girard, 1858 | taxon = Thaleichthys pacificus | authority = (J. Richardson, 1836) |synonyms=*''Lestidium parri'' Chapman, 1939 *''Osmerus albatrossis'' Jordan & Gilbert, 1898 *''Osmerus pacificus'' (Richardson, 1836) *''Salmo pacificus'' Richardson, 1836 *''Thaleichthys stevensi'' Girard, 1858 |synonyms_ref=<ref>{{GBIF|taxon=''Thaleichthys pacificus'' (Richardson, 1836)|id=2410903|access-date=7 May 2023}}</ref> }}

The '''eulachon''' ({{IPAc-en|ˈ|j|uː|l|ə|k|ɒ|n|,_|-|l|I|k|@|n}};<ref>{{Cite Merriam-Webster|eulachon|access-date=2025-06-19}}</ref> '''''Thaleichthys pacificus'''''), or the '''candlefish''', is a small anadromous species of smelt that spawns in some of the major river systems along the Pacific coast of North America from northern California to Alaska.

==Etymology== [[File:"Candlefish" or ooligan (Thaleichthys pacificus) here first ever documentation of this species by artist and explorer William Clark - Clark Family Collection- Volume 2. Voorhis Journal No. 2, page 60, February 25, 1806 (cropped).jpg|left|thumb|First ever documentation of this species recorded in the journal of the Lewis and Clark Expedition on February 25, 1806 at Fort Clatsop<ref>{{Cite journal |last=Ehrlich |first=George |date=1990 |title=The Illustrations in the Lewis and Clark Journals: One Artist or Two? |journal=Proceedings of the American Philosophical Society |volume=134 |issue=2 |pages=95–110 |jstor=986841 |issn=0003-049X}}</ref><ref>{{Cite web |last=Kris |date=2021-04-09 |title=Eulachon |url=https://lewis-clark.org/sciences/other-animals/eulachon/ |access-date=2024-12-01 |website=Discover Lewis & Clark |language=en-US}}</ref>]] The name "candlefish" derives from it being so fatty during spawning, with up to 15% of the total body weight in fat, that if caught, dried, and strung on a wick, it can be burned as a candle.<ref>{{cite web | url=https://www.nationalgeographic.com/history/article/150707-salvation-fish-canada-first-nations-animals-conservation-world | title='Salvation Fish' That Sustained Native People Now Needs Saving | website=National Geographic Society | date=7 July 2015 }}</ref><ref>{{cite web | url=https://www.youtube.com/watch?v=wEMQujyzHQA | title=Watch a Fish Transform from Animal to Candle {{pipe}} National Geographic | website=YouTube | date=15 July 2015 }}</ref>{{Better source needed|reason=The current source is insufficiently reliable (WP:NOTRS).|date=June 2024}} This is the name most often used by early explorers. The name ''eulachon'' (occasionally seen as '''oolichan''' {{IPAc-en|ˈ|uː|l|ᵻ|k|ɑː|n}}, '''ooligan''' {{IPAc-en|ˈ|uː|l|ᵻ|ɡ|ə|n}}, '''hooligan''' {{IPAc-en|ˈ|h|uː|l|ᵻ|ɡ|ə|n}}, '''oulachon''', and '''uthlecan''') is from the Chinookan language and the Chinook Jargon based on that language.{{citation needed|date=June 2025}} One of several theories for the origin of the name of the state of Oregon is that it was a corruption from the term "Oolichan Trail", the native trade route for oolichan oil. In some parts it is also known as "halimotkw", which can be translated as "savior fish" or "salvation fish", due to its availability for fishing often coming at the end of winter, when food supplies typically run low.<ref>{{cite web | url=https://www.nationalgeographic.com/history/article/150707-salvation-fish-canada-first-nations-animals-conservation-world | title='Salvation Fish' That Sustained Native People Now Needs Saving | website=National Geographic Society | date=7 July 2015 }}</ref>

The unrelated sablefish ''Anoplopoma fimbria'' is also called "candlefish" in the United Kingdom.

==Species description==

Eulachon are distinguished by the large canine-like teeth on the vomer bone and 19 to 31 rays in the anal fin. Like salmon and trout they have an adipose fin (aft of the dorsal); it is sickle-shaped. The paired fins are longer in male fish than in females. All fins have well-developed breeding tubercles (raised tissue "bumps") in ripe males, but these are poorly developed or absent in females. Adult coloration is brown or blue on the back extending to the top of the head, lighter to silvery white or light blue on the sides, and white on the ventral surface; speckling is extra fine, sparse, and restricted to the back.<ref name=NMFS/> Adults can reach maximum lengths of {{cvt|30|cm|in}} but most adults are between {{cvt|15|and|20|cm|in|round=0.5}}.<ref name=McGinnis>{{cite book|last=McGinnis|first=Samuel M.|title=Field guide to freshwater fishes of California|date=2006|publisher=University of California Press|location=Berkeley|isbn=0-520-23727-7|pages=202–203|edition=Revised}}</ref> Adults have striae on their operculum that aid in distinguishing ''Thaleichthys pacificus'' from other smelt.<ref name=cosewic2011>{{cite web|url=https://wildlife-species.canada.ca/species-risk-registry/virtual_sara/files/cosewic/sr_eulachon_0911_eng.pdf|title=COSEWIC assessment and status report on the Eulachon, Nass / Skeena Rivers population, Central Pacific Coast population and the Fraser River population ''Thaleichthys pacificus'' in Canada|year=2011|author=COSEWIC|publisher=Committee on the Status of Endangered Wildlife in Canada|location=Ottawa|access-date=7 May 2023}}</ref> They feed on plankton but only while at sea.<ref name=NMFS>{{cite web|title=Pacific Eulachon/Smelt (''Thaleichthys pacificus'')|url=http://www.nmfs.noaa.gov/pr/species/fish/pacificeulachon.htm|archive-url=https://web.archive.org/web/20140203172429/http://www.nmfs.noaa.gov/pr/species/fish/pacificeulachon.htm|archive-date=3 February 2014|work=NOAA Fisheries Office of Protected Resources|publisher=National Marine Fisheries Service|date=6 August 2013}}</ref>

==Ecology== Eulachon feed primarily on plankton as well as fish eggs, insect larvae, ocean debris and small crustaceans. It forms an important part of the diet of many ocean and shore predators, and serves as a prominent food source for people living near its spawning streams.

Eulachon, as anadromous fish, spend most of their adult lives in the ocean but return to their natal freshwater streams and rivers to spawn and die.<ref name=EPN>{{cite web|title=Eulachon of the Pacific Northwest A Life History |url=https://royalbcmuseum.bc.ca/exhibits/living-landscapes/northwest/eulachon/resources/lifehisreport.pdf|work=Living Landscapes Program, Royal BC Museum|date=January 11, 2006}}</ref> As such, one stream may see regular large runs of eulachon while a neighboring stream sees few or none at all. Regular annual runs are common but not entirely predictable, and occasionally a river which has large runs sees a year with no returns; the reasons for such variability are not known. The eulachon run is characteristic for the early portion being almost entirely male, with females following about midway through the run to its conclusion.{{citation needed|date=January 2014}} Males are easily distinguished from females during spawning by fleshy ridges which form along the length of their bodies.{{clarify|date=January 2014}}

==Economics and trade== {{no footnotes|section|date=May 2023}} [[Image:Eulachon smelt rendering camp.jpg|right|thumb|Eulachon rendering camp at the mouth of the Nass River, 1884.]] Indigenous communities of the Pacific Coast from California to Alaska have long made eulachon an important part of their diet, as well as a valuable trade item with peoples whose territories do not include spawning rivers. Eulachon are so important that the Nisga'a, for instance, define the beginning of the new year as the month of '''''Xsaak''''', literally translated as "to eat eulachons", when the fish returns to freshwater to spawn. This marks the end of winter foods and the start of feasting, both for the Nisga'a and the many animals that arrive at the Nass River at that time of year.<ref>{{Cite journal |last1=Turner |first1=Nancy J. |last2=Reid |first2=Andrea J. |date=November 2022 |title="When the Wild Roses Bloom": Indigenous Knowledge and Environmental Change in Northwestern North America |journal=GeoHealth |language=en |volume=6 |issue=11 |article-number=e2022GH000612 |doi=10.1029/2022GH000612 |issn=2471-1403 |pmc=9665002 |pmid=36398276 |bibcode=2022GHeal...6..612T }}</ref>

Eulachon is caught using traps, rakes, and nets, with other residents taking part in the exploitation of the large runs. Today harvested eulachon are typically stored frozen and thawed as needed. They may also be fried, dried, smoked, or canned. Eulachon are also processed for their rich oil. The usual process allows the fish to decompose (rot) for a week or more in a hole in the ground, then add boiling hot water and skim off the oil, which would rise to the surface, being less dense than water. Eulachon oil (also known as "Eulachon grease") is traded with inland communities; as a result, the trails over which the trade was conducted came to be known as grease trails. Other uses of eulachon by non-Natives include bait for sportfishing and food for cats and dogs.

==Conservation status== In November 2008, the National Marine Fisheries Service (NMFS) received a petition from the Cowlitz Tribe to list a distinct population segment (DPS) of eulachon from Washington, Oregon, and California, (the so-called Southern DPS) as an endangered or threatened species under the Endangered Species Act.<ref>{{cite web |url=http://www.nmfs.noaa.gov/pr/laws/esa/ |title=Endangered Species Act|date=28 April 2023 }}</ref> (ESA). NMFS found that this petition presented enough information to warrant conducting a status review of the species. Based on the status review NMFS proposed listing this species as threatened on March 13, 2009.<ref>{{cite web |title=Proposed listing status for Pacific eulachon |url=http://www.nmfs.noaa.gov/pr/pdfs/fr/fr74-10857.pdf |archive-url=https://web.archive.org/web/20090511021542if_/http://www.nmfs.noaa.gov/pr/pdfs/fr/fr74-10857.pdf |archive-date=2009-05-11}}</ref> On March 16, 2010, NOAA announced that the Southern DPS of eulachon will be listed as threatened under the ESA, effective on May 17, 2010 (See: the ''Federal Register'' notice published on May 18, 2010, at 74 FR 3178).<ref>{{cite web |url=http://www.nwr.noaa.gov/Other-Marine-Species/Eulachon.cfm |title=NOAA's Eulachon listing status history}}</ref> On September 6, 2017, the NMFS approved a recovery plan intended to serve as a blueprint for the protection and recovery of the southern Distinct Population Segment (DPS) of eulachon (''Thaleichthys pacificus'') using the best available science per the requirements of the Endangered Species Act.<ref>{{cite book |last1=United States. National Marine Fisheries Service. West Coast Region |url=https://purl.fdlp.gov/GPO/gpo88483 |title=Endangered Species Act Recovery Plan for the Southern Distinct Population Segment of Eulachon (''Thaleichthys pacificus'') |date=2017 |publisher=U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service |location=Portland, OR |archive-url=https://web.archive.org/web/20231203173402if_/https://permanent.fdlp.gov/gpo88483/final_eulachon_recovery_plan_09-06-2017-accessible.pdf |archive-date=2023-12-03 |url-status=live}}</ref><ref>{{Cite web |title=Eulachon, Thaleichthys pacificus |url=https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=34431&inline}}</ref>

In Canada, the Central Pacific Coast and Fraser River populations were classified as endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) in 2011.<ref name=cosewic2011/> At that time, the Nass / Skeena Rivers population was given threatened status, but this was downgraded to Special Concern status when the Nass / Skeena Rivers population was individually reassessed by COSEWIC in 2013.<ref name=cosewic2013>{{cite web|url=https://wildlife-species.canada.ca/species-risk-registry/virtual_sara/files/cosewic/sr_eulakane_eulachon_nass-skeena_1213_e.pdf|title=COSEWIC assessment and status report on the Eulachon, Nass/Skeena Rivers population, ''Thaleichthys pacificus'' in Canada|year=2013|author=COSEWIC|publisher=Committee on the Status of Endangered Wildlife in Canada|location=Ottawa|access-date=7 May 2023}}</ref> As of May 2023, a decision is pending on the listing of these populations under Schedule 1 of the Species at Risk Act.<ref>{{cite web|url=https://species-registry.canada.ca/index-en.html#/species?sortBy=commonNameSort&sortDirection=asc&pageSize=10&keywords=Thaleichthys%20pacificus|title=Species search|website=Species at risk public registry|access-date=7 May 2023|date=2 February 2021|publisher=Government of Canada}}</ref>

Overall, the species faces multiple threats, including overharvest, pollution, loss of freshwater spawning habitat due to logging, diversion and dam construction and climate change.<ref name=iucn/><ref name=ns/> Canadian spawning runs have been severely depleted compared to historic levels,<ref name=cosewic2013/> while abrupt declines were reported in the Columbia, Fraser and Klinaklini rivers in 1994.<ref name=iucn/>

==References== {{Reflist}} *{{ITIS |id=162051 |taxon=Thaleichthys pacificus |access-date=11 March 2006}} *[http://www.sitnews.net/JuneAllen/Ooligan/021703_ooligan.html The First Sign of Spring: OOLIGAN] *[http://www.nmfs.noaa.gov/pr/species/fish/pacificeulachon.htm National Marine Fisheries Service eulachon webpage]

==External links== *[http://www.fishbase.org/Summary/SpeciesSummary.cfm?genusname=Thaleichthys&speciesname=pacificus FishBase entry for Thaleichthys pacificus] *[https://www.communitystories.ca/v1/pm_v2.php?id=record_detail&fl=0&lg=English&ex=00000328 Preserving the Tradition of T'lina Making] - Virtual Museum Exhibit of Kwakwaka'wakw eulachon oil production *[https://www.cbc.ca/news/canada/british-columbia/bella-coola-eulachon-grease-project-revives-tradition-1.4722780 ''Central Coast First Nation preserves eulachon grease tradition as the fish returns to Bella Coola River''], Audrey McKinnon, CBC News, June 27, 2018, last opened Febr. 13, 2022 *[https://www.youtube.com/watch?v=sZYRl_4v2B4 ''Sinumwack: Bella Coola Oolichan Run''] (UBCIC, 1978) *[https://www.cbc.ca/news/canada/british-columbia/bella-coola-eulachon-grease-project-revives-tradition-1.4722780 ''Watch a Fish Transform From Animal to Candle''], National Geographic on YouTube, last opened Febr. 13, 2022

Category:First Nations culture in Canada Category:Fish of the Pacific Ocean Category:Native American culture Category:Osmeridae Category:Marine fish genera Category:Taxa named by Charles Frédéric Girard Category:Fish described in 1836 Category:ESA threatened species