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Brook Trout

Salvelinus fontinalis

Fish · family Salmonidae · order Salmoniformes

  1. G1
    Critically imperiled
  2. G2
    Imperiled
  3. G3
    Vulnerable
  4. G4
    Apparently secure
  5. G5
    Secure

NatureServe global rank G5: secure[2].

Updated October 30, 2026. Published by Humblebee.

Brook Trout
Photo: Photo by and (C)2007 Derek Ramsey ( Ram-Man ), CC BY-SA 2.5, via Wikimedia Commons.
Endangered Species Act
Not listed[1]
NatureServe global rank
G5 Secure[2]
Native in
22 states[3]
Longest recorded life
24 years[4]

The Brook Trout (Salvelinus fontinalis) is a fish in the salmon family, Salmonidae[5]. NatureServe ranks it G5 (Secure) worldwide, and it is not listed under the US Endangered Species Act[2][1].

Conservation status

NatureServe gives the Brook Trout a global rank of G5 (Secure) and a US national rank of N5 (Secure)[2][6]. The IUCN Red List category recorded by NatureServe is Least concern[7]. The species is not listed as endangered or threatened under the US Endangered Species Act in USFWS data checked on 2026-10-30[1]. Some states rank it lower than the national rank[8]. NatureServe says the recent population trend is uncertain, but likely fairly stable or slowly declining[9].

Status Value
Endangered Species Act[1] Not listed
NatureServe global rank[2] G5 (Secure)
NatureServe US rank[6] N5 (Secure)
IUCN Red List (via NatureServe)[7] Least concern

Where Brook Trout lives

NatureServe lists the Brook Trout as native in 22 US states and territories[3]. These include Maine, New York, Pennsylvania, Michigan, Wisconsin, Minnesota, Georgia and Tennessee[3]. It is listed as introduced, meaning not native, in many other states, including Alaska, California, Colorado, Montana, Oregon, Utah and Washington[10]. A state list shows where NatureServe records the fish, so it does not promise you will find one there[3][10].

Alaska: introduced, state rank SNAAKMaine: native, state rank S5MEWisconsin: native, state rank S5WIVermont: native, state rank S5VTNew Hampshire: native, state rank S5NHWashington: introduced, state rank SNAWAIdaho: introduced, state rank SNAIDMontana: introduced, state rank SNAMTNorth Dakota: introduced, state rank SNANDMinnesota: native, state rank SNRMNIllinois: introduced, state rank SNAILMichigan: native, state rank S4MINew York: native, state rank S5NYMassachusetts: native, state rank S4MAOregon: introduced, state rank SNAORNevada: introduced, state rank SNANVWyoming: introduced, state rank SNAWYSouth Dakota: introduced, state rank SNASDIowa: native, state rank S3IAIndiana: native, state rank S2INOhio: native, state rank S1OHPennsylvania: native, state rank S4PANew Jersey: native, state rank S3NJConnecticut: native, state rank S5CTRhode Island: native, state rank S5RICalifornia: introduced, state rank SNACAUtah: introduced, state rank SNAUTColorado: introduced, state rank SNACONebraska: introduced, state rank SNANEMissouri: not recordedMOKentucky: introduced, state rank SNAKYWest Virginia: native, state rank S5WVVirginia: native, state rank S4VAMaryland: native, state rank S3MDDelaware: introduced, state rank SNADEArizona: introduced, state rank SNAAZNew Mexico: introduced, state rank SNANMKansas: not recordedKSArkansas: introduced, state rank SNAARTennessee: native, state rank S3TNNorth Carolina: native, state rank S4NCSouth Carolina: native, state rank S1SCDistrict of Columbia: not recordedDCOklahoma: not recordedOKLouisiana: not recordedLAMississippi: not recordedMSAlabama: not recordedALGeorgia: native, state rank S2GAHawaii: not recordedHITexas: not recordedTXFlorida: not recordedFLPuerto Rico: not recordedPR
State presence as recorded by NatureServe[8].
Show state ranks (41 states)
StateRankMeaning
AlaskaSNANot Applicable
ArizonaSNANot Applicable
ArkansasSNANot Applicable
CaliforniaSNANot Applicable
ColoradoSNANot Applicable
ConnecticutS5Secure
DelawareSNANot Applicable
GeorgiaS2Imperiled
IdahoSNANot Applicable
IllinoisSNANot Applicable
IndianaS2Imperiled
IowaS3Vulnerable
KentuckySNANot Applicable
MaineS5Secure
MarylandS3Vulnerable
MassachusettsS4Apparently Secure
MichiganS4Apparently Secure
MinnesotaSNRNot Ranked
MontanaSNANot Applicable
NebraskaSNANot Applicable
NevadaSNANot Applicable
New HampshireS5Secure
New JerseyS3Vulnerable
New MexicoSNANot Applicable
New YorkS5Secure
North CarolinaS4Apparently Secure
North DakotaSNANot Applicable
OhioS1Critically Imperiled
OregonSNANot Applicable
PennsylvaniaS4Apparently Secure
Rhode IslandS5Secure
South CarolinaS1Critically Imperiled
South DakotaSNANot Applicable
TennesseeS3Vulnerable
UtahSNANot Applicable
VermontS5Secure
VirginiaS4Apparently Secure
WashingtonSNANot Applicable
West VirginiaS5Secure
WisconsinS5Secure
WyomingSNANot Applicable

Habitat

NatureServe records many habitat types for the Brook Trout, such as creeks, spring brooks, rivers, riffles, pools and deep or shallow water[11]. Most populations are found in clear, cool, well-oxygenated creeks, smaller rivers and lakes[12]. The fish like water around 14 to 16 C and do poorly where water stays above 20 C for long periods[12]. Some fish move into lakes or the sea to escape summer heat[12].

Habitat types recorded by NatureServe[11]

Size, diet and lifespan

NatureServe records a typical length of 40 cm (16 in)[13]. The adult diet is listed as piscivore and invertivore, which means it eats fish and animals without backbones[14]. It feeds on whatever is available, mostly insects and small crustaceans, and fish and crustaceans in salty water[15]. Females reach sexual maturity at 730 days of age[16]. The longest recorded lifespan in the wild is 24 years, which is a record and not a typical lifespan[4].

Trait Value
Typical length[13] 40 cm (16 in)
Longest recorded lifespan (AnAge)[4] 24 years (wild)
Female maturity[16] 730 days (about 2.0 years)
Food habits[14] Piscivore, Invertivore
Migration[17] non-migrant, local migrant

When to look for it

NatureServe says most feeding happens in early morning and evening[18]. Spawning takes place in late summer in the north or in fall in many areas, October to November[19]. Some populations move between fresh water and salt water, and the seaward trip usually happens in spring in northern areas[20]. On GBIF, most US observation records fall in June, July and August[21]. Those records show when people look and report, not how many fish there are[21].

January: 102 recordsJanFebruary: 73 recordsFebMarch: 254 recordsMarApril: 556 recordsAprMay: 1,073 recordsMayJune: 1,836 recordsJunJuly: 3,002 recordsJulAugust: 2,558 recordsAugSeptember: 1,761 recordsSepOctober: 1,200 recordsOctNovember: 301 recordsNovDecember: 915 recordsDec
US observation records on GBIF by month, all years. The three months with the most records are highlighted. Records show when people look and report, not how many animals there are[21].
Show records by month
MonthRecords
January102
February73
March254
April556
May1,073
June1,836
July3,002
August2,558
September1,761
October1,200
November301
December915

Where to see it

National Park Service species lists record Brook Trout as present in 48 park units[22]. Present means the park has a confirmed record, not that sightings are common.

And 24 more park units.

States with the most GBIF observation records: Pennsylvania, New Jersey, Wyoming, New York, Michigan[23]. These counts follow where people look and report, not population size.

Questions people ask

Is the Brook Trout endangered?
No. It is not listed as endangered or threatened under the US Endangered Species Act[1]. NatureServe ranks it G5 (Secure) globally[2].
Where does the Brook Trout live?
It is native in 22 US states and territories, including Maine, New York, Pennsylvania and Georgia[3]. It has also been introduced in many other states, including Alaska, Colorado and Oregon[10].
What does the Brook Trout eat?
It feeds on many small animals, mostly insects and small crustaceans[15]. NatureServe lists its adult diet as piscivore and invertivore[14].
How big is a Brook Trout?
NatureServe records a typical length of 40 cm (16 in)[13].
How long does a Brook Trout live?
The longest recorded lifespan in the wild is 24 years[4]. That is a record and not a typical lifespan[4].

Facts and sources

  1. Brook Trout is not listed as endangered or threatened under the US Endangered Species Act in USFWS ECOS data (checked 2026-10-30). USFWS ECOS
  2. NatureServe global conservation status rank for Brook Trout: G5 (Secure). NatureServe Explorer
  3. NatureServe lists Brook Trout as native in 22 US states and territories: Connecticut, Georgia, Iowa, Indiana, Massachusetts, Maryland, Maine, Michigan, Minnesota, North Carolina, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, South... NatureServe Explorer
  4. Maximum recorded lifespan in AnAge: 24 years in the wild. This is a record, not a typical lifespan. AnAge
  5. Brook Trout (Salvelinus fontinalis) is a fish in the family Salmonidae, order Salmoniformes. NatureServe Explorer
  6. NatureServe national rank in the United States: N5 (Secure). NatureServe Explorer
  7. IUCN Red List category as recorded by NatureServe: Least concern. NatureServe Explorer
  8. NatureServe state ranks for Brook Trout (map and table on this page). NatureServe Explorer
  9. NatureServe notes on trend for Brook Trout. NatureServe Explorer
  10. NatureServe lists Brook Trout as introduced (not native) in: Alaska, Arkansas, Arizona, California, Colorado, Delaware, Idaho, Illinois, Kentucky, Montana, North Dakota, Nebraska, New Mexico, Nevada, Oregon, South Dakota, Utah, Washington, Wyoming. NatureServe Explorer
  11. Habitat types NatureServe records for Brook Trout: Big river, Medium river, Creek, Spring/spring brook, High gradient, Moderate gradient, Low gradient, Riffle, Pool, Deep water, Shallow water, Bay/sound, River mouth/tidal river, Near shore. NatureServe Explorer
  12. NatureServe notes on habitat for Brook Trout. NatureServe Explorer
  13. Typical length recorded by NatureServe: 40 cm (16 in). NatureServe Explorer
  14. Adult food habits recorded by NatureServe: Piscivore, Invertivore. NatureServe Explorer
  15. NatureServe notes on food for Brook Trout. NatureServe Explorer
  16. Age at female sexual maturity in AnAge: 730 days (about 2.0 years). AnAge
  17. NatureServe migration category for Brook Trout: non-migrant, local migrant (populations can differ). NatureServe Explorer
  18. NatureServe notes on phenology for Brook Trout. NatureServe Explorer
  19. NatureServe notes on reproduction for Brook Trout. NatureServe Explorer
  20. NatureServe notes on migration for Brook Trout. NatureServe Explorer
  21. GBIF observation records of Brook Trout in the US by month (chart on this page). GBIF
  22. NPSpecies park lists recording Brook Trout as present (list on this page). NPS NPSpecies
  23. US states with the most GBIF observation records of Brook Trout: Pennsylvania, New Jersey, Wyoming, New York, Michigan. Record counts follow observer effort, not population size. GBIF

Status, range and habitat come from NatureServe Explorer (CC BY 4.0) and USFWS ECOS at the snapshot date. Listings change by federal rule. State lists are where NatureServe records the species, not a promise that you will see it there. Never name a place smaller than a state. GBIF and park records count observations and checklists. They show where and when people report the species, not how many animals live there.

NatureServe. 2026. NatureServe Explorer [web application]. NatureServe, Arlington, Virginia. Available https://explorer.natureserve.org. (Accessed: October 30, 2026). Licensed under CC BY 4.0; SpeciesFacts selected and summarized it.

Photo: Photo by and (C)2007 Derek Ramsey ( Ram-Man ), CC BY-SA 2.5, via Wikimedia Commons.