Lontra canadensis

(Schreber, 1777)

North American River Otter

G5Secure Found in 200 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
Least concernIUCN
Identity
Unique IDELEMENT_GLOBAL.2.102243
Element CodeAMAJF10010
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVertebrate Animal
IUCNLeast concern
CITESAppendix II
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomAnimalia
PhylumCraniata
ClassMammalia
OrderCarnivora
FamilyMustelidae
GenusLontra
Synonyms
Lutra canadensis(Schreber, 1777)
Other Common Names
Loutre de rivière (FR) North American Otter (EN) North American river otter (EN) Northern River Otter (EN) River Otter (EN)
Concept Reference
Jones, C., R. S. Hoffman, D. W. Rice, M. D. Engstrom, R. D. Bradley, D. J. Schmidly, C. A. Jones, and R. J. Baker. 1997. Revised checklist of North American mammals north of Mexico, 1997. Occasional Papers, Museum of Texas Tech University 173:1-20.
Taxonomic Comments
Formerly included in the genus Lutra. Recognition of subspecies has been disputed.
Conservation Status
Rank MethodExpertise without calculation
Review Date2016-04-04
Change Date1996-11-18
Edition Date1995-11-28
Edition AuthorsHammerson, G.
Range Extent20,000-2,500,000 square km (about 8000-1,000,000 square miles)
Number of Occurrences81 to >300
Rank Reasons
Large range in much of North America north of Mexico; population trend probably is relatively stable; recent reintroduction and management efforts have improved conservation status.
Range Extent Comments
Throughout most of North America north of Mexico, except the extreme southwestern U.S. Extirpated from large areas of the interior U.S. following European colonization. Has been reintroduced in some parts of the range (e.g., Colorado, Virginia).
Occurrences Comments
The large range likely is divisible into at least 100 element occurrences.
Threat Impact Comments
Local/regional declines were caused by unregulated trapping and degradation of riverine/riparian habitat. Oil contamination resulted in reduced habitat availability in Alaska (Bowyer et al. 1995).
Ecology & Habitat

Habitat

Streams, lakes, ponds, swamps, marshes, estuaries (in some areas), beaver flowages, exposed outer coast (Pacific Northwest, Alaska). When inactive, occupies hollow log, space under roots, log, or overhang, abandoned beaver lodge, dense thicket near water, or burrow of other animal; such sites also are used for rearing young. Highly associated with beaver on Mount Desert Island, Maine (Dubuc et al. 1990). Uses traditional haul-out sites along the banks of aquatic habitats. May travel long distances overland, particularly in snow.

Ecology

Home range typically is linear; 20-30 miles for a pair or male; less for females with young (Jackson 1961). May hunt over as much as 80-100 km of stream during the course of one year. In coastal Alaska, summer home range size averaged around 20 km of shoreline in males, 10 km in females, with ranges twice as large in oiled areas (Bowyer et al. 1995).

Population density of one per 2.2 miles has been recorded (Baker 1983). Density was estimated at one otter per 86 ha of coastal marsh in Louisiana (Shirley et al. 1988). In Idaho, density was one family group and 1-3 subadults or nonbreeding adults per 15 km of waterway, plus one breeding adult male for each 20-30 km of waterway (see Toweill and Tabor 1982). Density in coastal areas of the Gulf of Alaska was 0.30-0.85 otters/km of shoreline (Testa et al. 1994, Bowyer et al. 1995).

Reproduction

Implantation is delayed 8 months or more. Gestation, including delayed implantation, lasts 9-12 months. In many areas, births peak in late winter-early spring; parturition dates may not be closely synchronized within a given population. Litter size is 1-6 (average 2-3); 1 litter per year. Young may first enter water at about 7 weeks, are weaned at about 3 months, stay with mother for about a year. Male may rejoin family after young leave den. Females breed for the first time at 2 years. Males become sexually mature at 2 years, but may not breed successfully until 5-7 years old. Females evidently breed in alternate years in some areas (e.g., Alabama, Georgia), every year in Oregon (see Toweill and Tabor 1982).
Palustrine Habitats
HERBACEOUS WETLANDSCRUB-SHRUB WETLANDFORESTED WETLANDRiparian
Other Nations (2)
United StatesN5
ProvinceRankNative
MassachusettsS4Yes
VermontS5Yes
New MexicoSHYes
ConnecticutS5Yes
District of ColumbiaS1Yes
PennsylvaniaS4Yes
TennesseeS3Yes
GeorgiaS5Yes
Navajo NationS1Yes
North CarolinaS4Yes
MissouriS5Yes
WashingtonS4Yes
IdahoS4Yes
MinnesotaSNRYes
OhioS3Yes
New HampshireS5Yes
MississippiS4Yes
FloridaSNRYes
UtahS3Yes
OregonS4Yes
NebraskaS4Yes
VirginiaS4Yes
IowaS3Yes
ArizonaSH,SNAYes
MaineS5Yes
New YorkS5Yes
LouisianaS4Yes
DelawareS4Yes
South DakotaS3Yes
NevadaS2Yes
OklahomaS3Yes
New JerseyS4Yes
MontanaS5Yes
ArkansasS5Yes
West VirginiaS4Yes
MarylandS5Yes
IllinoisS2Yes
KentuckyS3Yes
South CarolinaS4Yes
WyomingS3Yes
Rhode IslandS4Yes
AlabamaS4Yes
WisconsinS4Yes
TexasS3Yes
IndianaS5Yes
MichiganS4Yes
North DakotaS3Yes
AlaskaS5Yes
KansasS3Yes
ColoradoS3Yes
CaliforniaSNRYes
CanadaN5
ProvinceRankNative
Nova ScotiaS5Yes
OntarioS5Yes
QuebecS5Yes
British ColumbiaS5Yes
ManitobaS5Yes
LabradorS5Yes
SaskatchewanS3Yes
Island of NewfoundlandS5Yes
AlbertaS4Yes
NunavutSUYes
Yukon TerritoryS4Yes
Prince Edward IslandSUYes
New BrunswickS5Yes
Northwest TerritoriesS4Yes
Threat Assessments
ThreatScopeSeverityTiming
1 - Residential & commercial developmentHigh (continuing)
1.1 - Housing & urban areasHigh (continuing)
1.2 - Commercial & industrial areasHigh (continuing)
2 - Agriculture & aquacultureHigh (continuing)
2.1 - Annual & perennial non-timber cropsHigh (continuing)
2.3 - Livestock farming & ranchingHigh (continuing)
2.4 - Marine & freshwater aquacultureHigh (continuing)
3 - Energy production & miningHigh (continuing)
3.2 - Mining & quarryingHigh (continuing)
5 - Biological resource useHigh (continuing)
5.1 - Hunting & collecting terrestrial animalsHigh (continuing)
5.3 - Logging & wood harvestingHigh (continuing)
7 - Natural system modificationsHigh (continuing)
7.2 - Dams & water management/useHigh (continuing)
8 - Invasive & other problematic species, genes & diseasesHigh (continuing)
8.2 - Problematic native species/diseasesHigh (continuing)
9 - PollutionHigh (continuing)
9.1 - Domestic & urban waste waterInsignificant/negligible or past
9.2 - Industrial & military effluentsHigh (continuing)
9.3 - Agricultural & forestry effluentsHigh (continuing)
9.5 - Air-borne pollutantsHigh (continuing)

Roadless Areas (200)
Alaska (40)
AreaForestAcres
Bay of PillarsTongass National Forest27,492
Behm IslandsTongass National Forest4,777
Boston BarChugach National Forest53,617
ChichagofTongass National Forest555,858
Chilkat-West Lynn CanalTongass National Forest199,772
ChristovalTongass National Forest9,129
College FiordChugach National Forest1,130,818
Dall IslandTongass National Forest105,780
Douglas IslandTongass National Forest28,065
EudoraTongass National Forest195,022
Fidalgo-GravinaChugach National Forest257,968
GravinaTongass National Forest37,381
Hoonah SoundTongass National Forest79,764
HyderTongass National Forest121,723
Juneau UrbanTongass National Forest101,581
Juneau-Skagway IcefieldTongass National Forest1,187,268
KartaTongass National Forest52,117
Kenai MountainsChugach National Forest306,600
KogishTongass National Forest65,216
LindenbergTongass National Forest25,855
Mansfield PeninsulaTongass National Forest54,991
Middle KruzofTongass National Forest14,724
Nellie JuanChugach National Forest713,697
North BaranofTongass National Forest314,089
North KruzofTongass National Forest33,146
North KupreanofTongass National Forest114,660
North RevillaTongass National Forest215,430
Outer IslandsTongass National Forest99,862
Port AlexanderTongass National Forest120,681
RedoubtTongass National Forest68,347
RevillaTongass National Forest29,298
RhineTongass National Forest23,010
Sitka SoundTongass National Forest13,459
Sitka UrbanTongass National Forest112,003
South KruzofTongass National Forest55,193
SukkwanTongass National Forest44,369
Taku-SnettishamTongass National Forest664,928
Tenakee RidgeTongass National Forest20,527
Twenty MileChugach National Forest198,775
Yakutat ForelandsTongass National Forest323,648
Arizona (4)
AreaForestAcres
Arnold MesaPrescott National Forest12,286
Black CanyonPrescott National Forest10,683
Lime CreekTonto National Forest42,568
MazatzalTonto National Forest16,942
California (32)
AreaForestAcres
Bell QuinbyShasta-Trinity National Forest11,556
Butt Mtn.Lassen National Forest8,217
Caples CreekEldorado National Forest17,854
Castle PeakTahoe National Forest14,974
Cherry LakeStanislaus National Forest1,106
Chips CreekPlumas National Forest12,940
Cow CreekSix Rivers National Forest1,271
Cow CreekShasta-Trinity National Forest22,627
Devil GulchSierra National Forest30,490
EagleShasta-Trinity National Forest6,553
East YubaTahoe National Forest17,968
Ferguson RidgeSierra National Forest6,104
Granite ChiefTahoe National Forest6,546
Grouse LakesTahoe National Forest19,085
Little French CShasta-Trinity National Forest11,529
North Fork SmithSix Rivers National Forest37,898
Orleans Mtn.Klamath National Forest49,090
Orleans Mtn. BSix Rivers National Forest17,183
Orleans Mtn. CSix Rivers National Forest15,589
ParsnipModoc National Forest8,485
PowleyModoc National Forest6,268
RussianKlamath National Forest21,771
SiskiyouKlamath National Forest54,039
Siskiyou BSix Rivers National Forest18,871
SnoozerKlamath National Forest23,414
Snow MountainMendocino National Forest14,457
SoldierModoc National Forest10,102
Tragedy - Elephants BackEldorado National Forest20,866
Trumbull PeakStanislaus National Forest6,164
Ukonom CreekKlamath National Forest4,621
WaterhouseStanislaus National Forest4,394
West GirardShasta-Trinity National Forest37,516
Colorado (1)
AreaForestAcres
Dome PeakRoutt NF35,716
Florida (1)
AreaForestAcres
Alexander Springs CreekOcala National Forest2,954
Idaho (7)
AreaForestAcres
Bighorn - WeitasNez Perce-Clearwater National Forest254,845
Borah PeakSalmon-Challis National Forest130,463
Boulder - White CloudsSalmon-Challis National Forest139,297
Boulder - White CloudsSawtooth National Forest322,653
Lemhi RangeSalmon-Challis National Forest308,533
North Lochsa SlopeNez Perce-Clearwater National Forest117,662
Peace RockBoise National Forest191,734
Minnesota (6)
AreaForestAcres
Baker - Homer - Brule LakesSuperior National Forest6,712
Brule Lake - Eagle MountainSuperior National Forest12,380
Cabin CreekSuperior National Forest6,071
Phantom LakeSuperior National Forest6,521
Tait LakeSuperior National Forest6,327
Wood LakeSuperior National Forest596
Missouri (2)
AreaForestAcres
Irish Rare II Study AreaMark Twain National Forest1,226
Spring Creek Rare II Study AreaMark Twain National Forest4,899
Montana (13)
AreaForestAcres
Bear - Marshall - Scapegoat - SwanLolo National Forest118,485
Bear - Marshall - Scapegoat - SwanLewis and Clark National Forest344,022
Big LogHelena National Forest8,954
Bmss Ra 1485Flathead National Forest334,275
Cabin Creek Wildlife Management Area OcdGallatin National Forest35,048
Cabinet Face East #671Kootenai National Forest50,326
HolterHelena National Forest1,965
HoodooLolo National Forest105,162
Hyalite - Porcupine - Buffalo Horn Wilderness Study AreaGallatin National Forest143,991
Lebeau RA 1507Flathead National Forest5,450
MadisonGallatin National Forest127,859
North AbsarokaGallatin National Forest159,075
Scotchman Peaks (MT)Kootenai National Forest53,909
Nevada (1)
AreaForestAcres
Rose - Alum CreekHumboldt-Toiyabe National Forest853
New Hampshire (6)
AreaForestAcres
Great Gulf Ext.White Mountain National Forest15,110
JobildunkWhite Mountain National Forest3,660
Mt. Wolf - Gordon PondWhite Mountain National Forest11,846
PemigewassetWhite Mountain National Forest32,255
Presidential - Dry River ExtWhite Mountain National Forest10,555
Wild RiverWhite Mountain National Forest46,878
New Mexico (4)
AreaForestAcres
Alamo CanyonSanta Fe National Forest8,639
Columbine - Hondo Wilderness Study AreaCarson National Forest43,739
LemitasSanta Fe National Forest8,129
Wheeler Peak WildernessCarson National Forest2,677
North Carolina (6)
AreaForestAcres
Catfish Lake NorthCroatan National Forest11,299
Harper CreekPisgah National Forest7,325
Lost CovePisgah National Forest5,944
Overflow CreekNantahala National Forest3,379
South Mills RiverPisgah National Forest8,588
Wilson CreekPisgah National Forest4,863
Oklahoma (1)
AreaForestAcres
Beech CreekOuachita National Forest8,303
Oregon (22)
AreaForestAcres
BuckhornWallowa-Whitman National Forest17,180
Bull Of The WoodsMt. Hood National Forest8,843
EagleMt. Hood National Forest16,841
HellholeUmatilla National Forest65,679
Maiden PeakWillamette National Forest9,627
Maiden PeakDeschutes National Forest26,432
Mt. JeffersonDeschutes National Forest2,282
Mt. BaileyUmpqua National Forest18,401
North KalmiopsisSiskiyou National Forests91,560
North PaulinaDeschutes National Forest19,670
Opal CreekWillamette National Forest5,417
Roaring RiverMt. Hood National Forest27,316
Salmon - HuckleberryMt. Hood National Forest17,570
Sky Lakes AWinema National Forest3,940
Snake RiverWallowa-Whitman National Forest31,229
South PaulinaDeschutes National Forest9,074
TahkenitchSiuslaw National Forest5,799
Twin MountainWallowa-Whitman National Forest58,533
Umpqua SpitSiuslaw National Forest2,090
Waldo - FujiWillamette National Forest15,273
Wind CreekMt. Hood National Forest5,438
WoahinkSiuslaw National Forest5,309
Pennsylvania (3)
AreaForestAcres
CornplanterAllegheny National Forest2,929
Minister ValleyAllegheny National Forest1,417
Tracy RidgeAllegheny National Forest9,034
Tennessee (1)
AreaForestAcres
Sampson Mountain AdditionCherokee National Forest3,064
Texas (1)
AreaForestAcres
Big CreekNational Forests in Texas1,447
Utah (2)
AreaForestAcres
0401001Ashley National Forest11,705
Stump CreekCaribou National Forest355
Vermont (3)
AreaForestAcres
Bread LoafGreen Mountain and Finger Lakes National Forests1,768
Griffith Lake 09084Green Mountain and Finger Lakes National Forests1,833
Wilder Mountain 09082Green Mountain and Finger Lakes National Forests8,759
Virginia (5)
AreaForestAcres
Broad RunJefferson National Forest10,971
Garden MountainJefferson National Forest3,960
North Fork PoundJefferson National Forest4,757
North MountainJefferson National Forest8,377
Peters Mountain Addition BJefferson National Forest2,909
Washington (19)
AreaForestAcres
Blue SlideWenatchee National Forest17,505
Dixon MountainGifford Pinchot National Forest6,339
EntiatWenatchee National Forest72,617
Glacier Peak BMt Baker-Snoqualmie National Forest19,328
Glacier Peak LMt Baker-Snoqualmie National Forest14,084
Goat Rocks AdjWenatchee National Forest6,108
Green MountainOlympic National Forest4,617
Heather LakeWenatchee National Forest10,628
Jupiter RidgeOlympic National Forest10,148
Mt. Baker Noisy - DiobsudMt Baker-Snoqualmie National Forest56,039
Mt. BaldyOlympic National Forest3,557
Nason RidgeWenatchee National Forest19,329
QuartzWenatchee National Forest8,550
Rock CreekWenatchee National Forest32,239
South QuinaultOlympic National Forest11,081
TaneumWenatchee National Forest26,140
Thorp Mtn.Wenatchee National Forest22,717
Twin LakesWenatchee National Forest22,496
Willow SpringsUmatilla National Forest10,414
West Virginia (2)
AreaForestAcres
Gauley MountainMonongahela National Forest13,285
Tea Creek MountainMonongahela National Forest8,295
Wyoming (18)
AreaForestAcres
0401035Ashley National Forest5,465
0401036Ashley National Forest6,309
Beartooth Proposed WildernessShoshone National Forest16,837
Grayback RidgeBridger-Teton National Forest295,113
Gros Ventre MountainsBridger-Teton National Forest106,418
Middle ForkShoshone National Forest51,772
Pacific Creek - Blackrock CreekBridger-Teton National Forest24,658
Phillips RidgeBridger-Teton National Forest10,108
ReefShoshone National Forest16,817
Salt River RangeBridger-Teton National Forest235,661
Sleeping GiantShoshone National Forest5,176
South Beartooth HighwayShoshone National Forest105,570
Spread Creek - Gros Ventre RiverBridger-Teton National Forest166,097
Teton Corridor TrailheadsBridger-Teton National Forest286
Wapiti Valley NorthShoshone National Forest18,345
Wapiti Valley SouthShoshone National Forest43,517
West Slope TetonsTarghee National Forest47,448
West Slope WindsBridger-Teton National Forest143,252
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