Pituophis catenifer - (Blainville, 1835)
Gophersnake
Other English Common Names: Gopher Snake, gophersnake
Taxonomic Status: Accepted
Related ITIS Name(s): Pituophis catenifer (Blainville, 1835) (TSN 209400)
French Common Names: couleuvre nez mince
Unique Identifier: ELEMENT_GLOBAL.2.103070
Element Code: ARADB26020
Informal Taxonomy: Animals, Vertebrates - Reptiles - Snakes
 
Kingdom Phylum Class Order Family Genus
Animalia Craniata Reptilia Squamata Colubridae Pituophis
Genus Size: B - Very small genus (2-5 species)
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Concept Reference
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Concept Reference: Collins, J. T. 1990. Standard common and current scientific names for North American amphibians and reptiles. 3rd ed. Society for the Study of Amphibians and Reptiles. Herpetological Circular No. 19. 41 pp.
Concept Reference Code: B90COL01NAUS
Name Used in Concept Reference: Pituophis catenifer
Taxonomic Comments: Pituophis catenifer formerly was included in P. melanoleucus. In recent years many authors have regarded the gopher snakes and bullsnake as a species (P. catenifer ) distinct from the pine snake (P. melanoleucus) and Louisiana pine snake (P. ruthveni). This classification, though not unequivocally supported by available data, has been adopted in this database. Following is some of the nomenclatural history.

Sweet (1984) recognized four groups within P. melanoleucus (former sense) based on differences in cranial morphology and evidence of distributional contacts with little or no intergradation: melanoleucus (4 eastern races); sayi and affinis; catenifer (6 western races); and vertebralis (plus bimaris and insularis). However these were retained as subspecies of melanoleucus by Sweet and Parker (1990).

Knight (1986) indicated that the bullsnake (subspecies sayi) clearly is alligned with the eastern subspecies (pine snakes), not with the western gopher snakes. Based on a phenetic study, Reichling (1995) also concluded that sayi is more closely allied with the eastern pine snakes than with the western subspecies. However, Knight's conclusions were based largely on snout morphology (premaxillary-nasal articulation), which Rodriguez-Robles and De Jesus-Escober (2000) found to be so variable that it cannot be reliably used to differentiate between snakes of this species complex.

Reichling's (1995) analysis led him to conclude that ruthveni is phenetically distinct and is a valid evolutionary species, though he referred to it consistently as P. m. ruthveni, probably in acknowledgment that the status of the nominal Pituophis subspecies still need further study.

Rodriguez-Robles and De Jesus-Escobar (2000) examined rangewide mtDNA variation in Pituophis and found two divergent, allopatric segments: (1) the lodingi-melanoleucus-mugitus eastern pinesnake clade and (2) the affinis-annectens-bimaris-catenifer-deserticola-sayi-ruthveni-vertebralis clade. These two clades were recognized as distinct species (P. melanoleucus and P. catenifer ). The taxon ruthveni was also recognized as a distinct species because it is a diagnosable allopatric entity. However, it has strong genetic affinities to sayi--some ruthveni are more closely related to sayi than to other ruthveni. This renders P. catenifer polyphyletic and is arguably a good basis for rejecting P. ruthveni as a distinct species. Clearly, further research is needed to clarify relationships.

Grismer (2001) presented information suggesting that P. vertebralis (including bimaris) and P. insulanus of Baja California should be regarded as specifically distinct from P. catenifer.

Rodriguez-Robles and De Jesus-Escobar (2000) stated that some of the subspecies of P. catenifer in western North America may not deserve taxonomic recognition, due to minor differences and extensive intergradation.
Conservation Status
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NatureServe Status

Global Status: G5
Global Status Last Reviewed: 06Oct2015
Global Status Last Changed: 09Nov1998
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G5 - Secure
Reasons: Large range from southern Canada to Mexico; common in many areas.
Nation: United States
National Status: N5 (05Oct1996)
Nation: Canada
National Status: N4 (02Feb2016)

U.S. & Canada State/Province Status
United States Arizona (S5), California (SNR), Colorado (S5), Idaho (S5), Illinois (S4), Indiana (SNR), Iowa (S4), Kansas (S5), Minnesota (S3), Missouri (SNR), Montana (S5), Navajo Nation (S5), Nebraska (S5), Nevada (S5), New Mexico (S5), North Dakota (SNR), Oklahoma (S5), Oregon (S5), South Dakota (S5), Texas (SNR), Utah (S5), Washington (S5), Wisconsin (S2S3), Wyoming (S4)
Canada Alberta (S3), British Columbia (S2S3), Saskatchewan (S4)

Other Statuses

Implied Status under the Committee on the Status of Endangered Wildlife in Canada (COSEWIC):PS:T
Comments on COSEWIC: Pituophis catenifer subspecies deserticola was designated Threatened in May 2002. Status re-examined and confirmed in May 2013.
IUCN Red List Category: LC - Least concern

NatureServe Global Conservation Status Factors

Range Extent: >2,500,000 square km (greater than 1,000,000 square miles)
Range Extent Comments: The range extends from southern British Columbia, southern Alberta, southern Saskatchewan, Minnesota, and Indiana south through almost all of western and central North America to northern Baja California (Grismer 2002) (or to southern Baja California if P. vertebralis is included in P. catenifer; Rodriguez-Robles and De Jesus-Escobar 2000), Sinaloa, and Zacatecas.

Number of Occurrences: > 300
Number of Occurrences Comments: This species is represented by hundreds of occurrences or subpopulations (see map in Sweet and Parker 1990).

Population Size: >1,000,000 individuals
Population Size Comments: Total adult population size is unknown but certainly exceeds 100,000 and probably exceeds 1,000,000. This snake is relatively common in many areas.

Number of Occurrences with Good Viability/Integrity: Very many (>125)

Overall Threat Impact: Medium
Overall Threat Impact Comments: No major threats exist. Local declines have occurred in areas with extensive, intensive agricultural or urban development, but these snakes persist in semiagricultural landscapes and rural residential areas.

Short-term Trend: Relatively Stable (<=10% change)
Short-term Trend Comments: Extent of occurrence, area of occupancy, number of subpopulations, and population size probably are relatively stable or declining at a rate of less than 10 percent over 10 years or three generations.

Long-term Trend: Decline of <30% to increase of 25%

Intrinsic Vulnerability: Moderately vulnerable

Other NatureServe Conservation Status Information

Distribution
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Global Range: (>2,500,000 square km (greater than 1,000,000 square miles)) The range extends from southern British Columbia, southern Alberta, southern Saskatchewan, Minnesota, and Indiana south through almost all of western and central North America to northern Baja California (Grismer 2002) (or to southern Baja California if P. vertebralis is included in P. catenifer; Rodriguez-Robles and De Jesus-Escobar 2000), Sinaloa, and Zacatecas.

U.S. States and Canadian Provinces
Color legend for Distribution Map
Endemism: occurs (regularly, as a native taxon) in multiple nations

U.S. & Canada State/Province Distribution
United States AZ, CA, CO, IA, ID, IL, IN, KS, MN, MO, MT, ND, NE, NM, NN, NV, OK, OR, SD, TX, UT, WA, WI, WY
Canada AB, BC, SK

Range Map
Note: Range depicted for New World only. The scale of the maps may cause narrow coastal ranges or ranges on small islands not to appear. Not all vagrant or small disjunct occurrences are depicted. For migratory birds, some individuals occur outside of the passage migrant range depicted.

Range Map Compilers: NatureServe, 2005


U.S. Distribution by County Help
State County Name (FIPS Code)
IA Adams (19003), Allamakee (19005), Black Hawk (19013), Boone (19015), Butler (19023), Clinton (19045), Dallas (19049), Guthrie (19077), Jasper (19099), Johnson (19103), Linn (19113), Madison (19121), Marion (19125), Muscatine (19139), Polk (19153), Ringgold (19159), Story (19169), Taylor (19173), Union (19175), Warren (19181)
ID Ada (16001), Adams (16003), Bingham (16011), Blaine (16013), Butte (16023), Camas (16025), Cassia (16031), Custer (16037), Elmore (16039), Franklin (16041), Gooding (16047)*, Jefferson (16051), Jerome (16053)*, Lemhi (16059), Lincoln (16063), Nez Perce (16069), Owyhee (16073), Twin Falls (16083), Valley (16085), Washington (16087)*
MN Anoka (27003), Benton (27009), Carver (27019), Chisago (27025), Dakota (27037), Fillmore (27045), Goodhue (27049), Hennepin (27053), Houston (27055), Isanti (27059), Marshall (27089), Mille Lacs (27095), Pine (27115), Ramsey (27123), Redwood (27127)*, Renville (27129)*, Scott (27139), Sherburne (27141), Wabasha (27157), Washington (27163), Winona (27169), Yellow Medicine (27173)
WI Buffalo (55011), Burnett (55013), Columbia (55021), Crawford (55023), Dane (55025), Dunn (55033), Grant (55043), Iowa (55049), Jackson (55053), La Crosse (55063), Monroe (55081), Pepin (55091), Polk (55095), Richland (55103), Sauk (55111), Trempealeau (55121), Vernon (55123)
WY Big Horn (56003), Campbell (56005), Park (56029), Sweetwater (56037)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
07 Platte-Spunk (07010201)+, Clearwater-Elk (07010203)+, Crow (07010204)+, Twin Cities (07010206)+, Rum (07010207)+, Hawk-Yellow Medicine (07020004)+, Lower Minnesota (07020012)+, Upper St. Croix (07030001)+, Kettle (07030003)+, Lower St. Croix (07030005)+, Rush-Vermillion (07040001)+, Cannon (07040002)+, Buffalo-Whitewater (07040003)+, Zumbro (07040004)+, La Crosse-Pine (07040006)+, Black (07040007)+, Root (07040008)+, Lower Chippewa (07050005)+, Coon-Yellow (07060001)+, Upper Iowa (07060002)+, Grant-Little Maquoketa (07060003)+*, Castle Rock (07070003)+, Lower Wisconsin (07070005)+, Kickapoo (07070006)+, Copperas-Duck (07080101)+, Lower Wapsipinicon (07080103)+, South Skunk (07080105)+, West Fork Cedar (07080204)+, Middle Cedar (07080205)+, Lower Cedar (07080206)+, Lower Iowa (07080209)+, Pecatonica (07090003)+, Middle Des Moines (07100004)+, North Raccoon (07100006)+, South Raccoon (07100007)+, Lake Red Rock (07100008)+
09 Snake (09020309)+
10 Nowood (10080008)+, Shoshone (10080014)+, Little Powder (10090208)+, Platte (10240012)+, Upper Grand (10280101)+, Thompson (10280102)+
14 Upper Green-Slate (14040103)+, Bitter (14040105)+, Upper Green-Flaming Gorge Reservoir (14040106)+
16 Middle Bear (16010202)+
17 Idaho Falls (17040201)+, Blackfoot (17040207)+, Lake Walcott (17040209)+, Raft (17040210)+, Goose (17040211)+, Upper Snake-Rock (17040212)+, Salmon Falls (17040213)+, Big Lost (17040218)+, Big Wood (17040219)+, Camas (17040220)+, Little Wood (17040221)+, C. J. Idaho (17050101)+, Bruneau (17050102)+, Middle Snake-Succor (17050103)+, Upper Owyhee (17050104)+, South Fork Owyhee (17050105)+, Boise-Mores (17050112)+, Lower Boise (17050114)+, Weiser (17050124)+, Lower Snake-Asotin (17060103)+, Upper Salmon (17060201)+, Pahsimeroi (17060202)+, Middle Salmon-Panther (17060203)+, Lower Middle Fork Salmon (17060206)+, Lower Salmon (17060209)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
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Basic Description: A large, blotched snake.
General Description: Dorsum yellowish or cream with numerous dark blotches; usually a dark stripe across the head between the eyes and from each eye to the angle of the jaw; belly usually cream or yellowish with dark spots; dorsal scales keeled; anal scale single; usually four prefrontal scales; vertical keel at opening of windpipe; maximum total length around 280 cm but rarely more than 180 cm.


Diagnostic Characteristics: Differs from other similar species by having the following combination of characteristics: keeled scales, 4 prefrontals, and an undivided anal. Rat snakes (ELAPHE) and kingsnakes (LAMPROPELTIS), have only two prefrontal scales. Also, ELAPHE has a divided anal plate. Whipsnakes (MASTICOPHIS), racers (COLUBER), and indigo snakes (DRYMARCHON) have smooth body scales.
Reproduction Comments: The mating period extends from April to early June over much of the range (Ernst and Barbour 1989). Eggs are laid as early as June in some areas or as late as August in other regions (Ernst and Barbour 1989). Clutch size is 2-24. Generally individual females produce one clutch per year. Incubation typically takes 50-100 days, with 70-75 days most common (Parker and Brown 1980, Ernst and Barbour 1989). In many areas, hatchlings emerge in August and September. In Utah, males reach sexually maturity in 1-2 years, females in 3-5 years (Parker and Brown 1980). Females appear to have an annual breeding cycle (Fitch 1970, Diller and Wallace 1996).
Ecology Comments: Population density was estimated at 0.3-1.3/ha in Utah and Idaho (Parker and Brown 1980, Nussbaum 1983).

This snake is remarkably variable in its behavior. Some individuals lie motionless when approached, remaining passive even when handled. Others respond to approach by coiling and striking (often lunging forward and grunting with each strike), hissing loudly, and vibrating the tail. The jaws may be spread, giving the head the triangular shape typical of rattlesnakes. In dry vegetation the vibrating tail may produce a sound resembling that made by a rattlesnakes rattle. Some individuals produce a rattling hiss that closely resembles the sound of a rattlesnakes rattle. Source: Hammerson (1999).

Non-Migrant: Y
Locally Migrant: Y
Long Distance Migrant: N
Mobility and Migration Comments: In Utah, migrated an average of about 500 m between winter den and summer range (Parker and Brown 1980).

Imler (1945) recaptured 11 snakes that had moved less than 100 m, but reported one snake moving 2.4 km. In Kansas, Fitch (1958) reported movements between captures of 94, 128, and 823 m. Radio-telemetered snakes in Kansas moved an average of 142 m in a day (Fitch and Shirer 1971). Home range was estimated at 1-2 ha in Utah (Parker and Brown 1980).

In west-central California, four males had home ranges of 1.0-2.3 ha (mean 1.7 ha) (95% convex polygon); maximum range length was a few hundred meters (Rodriguez-Robles 2003).

Palustrine Habitat(s): HERBACEOUS WETLAND, Riparian, SCRUB-SHRUB WETLAND
Terrestrial Habitat(s): Bare rock/talus/scree, Cropland/hedgerow, Desert, Grassland/herbaceous, Old field, Savanna, Shrubland/chaparral, Suburban/orchard, Woodland - Conifer, Woodland - Hardwood, Woodland - Mixed
Special Habitat Factors: Burrowing in or using soil, Fallen log/debris, Standing snag/hollow tree
Habitat Comments: This species occurs in a wide range of habitats, extending from lowlands to mountains: desert, prairie, shrubland, woodland, open coniferous forest, farmland, and marshes. Midwestern populations inhabit prairies; western and Mexican populations range from coastal grasslands and forests through deserts into montane forests (Sweet and Parker 1990). This snake is terrestrial, fossorial, and arboreal. It remains underground in cold weather and during the hot midday period in summer; it may occupy mammal burrows (Schroder 1950, Fitch 1958) or dig its own burrow, aided by the pointed snout and enlarged rostral scale. Carpenter (1982) estimated that burrowing Pituophis could move up to 3,400 cubic cm of soil in an hour. Eggs are deposited in burrows excavated by females in loose soil, in spaces beneath large rocks or logs, or possibly in small mammal burrows.
Adult Food Habits: Carnivore
Immature Food Habits: Carnivore
Food Comments: Feeds primarily on small mammals; also eats birds and their eggs, lizards, small snakes and snake eggs, and insects; lizards and insects are more common in the diet of juveniles than in that of adults. Forages actively and locates prey either by olfaction or sight (Dyrkacz and Corn 1974, Chiszar et al. 1980). Often forages underground, but in some areas also commonly climbs trees to prey on nesting birds (e.g., Eichhorn and Koenig 1992).

See Diller and Johnson (1988) for predation rate on small mammals in southwestern Idaho.

Adult Phenology: Diurnal, Hibernates/aestivates
Immature Phenology: Diurnal, Hibernates/aestivates
Phenology Comments: Activity occurs from about April through October in the north, mostly March through November farther south(Nussbaum et al. 1983, Tennant 1984). In southwestern Idaho, seasonal activity peaked in late May and early June (Diller and Wallace 1996). Generally this snake is diurnal, but it may be active at night, largely fossorial, or exhibit bimodal morning and evening activity in hot weather.
Length: 168 centimeters
Economic Attributes Not yet assessed
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Management Summary Not yet assessed
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Population/Occurrence Delineation
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Group Name: Medium And Large Colubrid Snakes

Use Class: Not applicable
Minimum Criteria for an Occurrence: Occurrences are based on evidence of historical presence, or current and likely recurring presence, at a given location. Such evidence minimally includes collection or reliable observation and documentation of one or more individuals (including eggs) in or near appropriate habitat where the species is presumed to be established and breeding.
Separation Barriers: Busy highway or highway with obstructions such that snakes rarely if ever cross successfully; major river, lake, pond, or deep marsh (this barrier pertains only to upland species and does not apply to aquatic or wetland snakes); densely urbanized area dominated by buildings and pavement.
Separation Distance for Unsuitable Habitat: 1 km
Separation Distance for Suitable Habitat: 10 km
Separation Justification: Available information on movements of colubrid snakes is limited to a small minority of species. These data indicate that nearly all species have home ranges smaller or much smaller than 25 ha (e.g., less than 3 ha, Pituophis catenifer in California, Rodriguez-Robles 2003), with some up to about 75 ha (Heterodon platirhinos, average 50 ha, Plummer and Mills 2000), and the largest up to 225 ha in the biggest colubrids (Drymarchon, summer mean 50-100 ha, USFWS 1998).

Radiotelemetry data for Pantherophis indicate that residents of hibernacula that are 1-2 km apart (with suitable intervening habitat) probably interbreed (Prior et al. 1997, Blouin-Demers and Weatherhead 2002). However, "evidence of genetic structure even over short distances (e.g., 2-20 km) implies that gene flow among rat snake populations can be easily disrupted" (Prior et al. 1997). Loughheed et al. (1999) found evidence of substantial genetic exchange among local hibernacula (< 6 km apart), but gene flow over distances of 10s of km appears to be substantially less. Based on extensive radio-tracking data, Blouin-Demers and Weatherhead (2002) found that home range size of Pantherophis averaged 18.5 ha and ranged up to 93 ha; based on the most mobile individuals, Pantherophis from hibernacula up to 8 km apart can come together for mating. Pantherophis and probably other colubrids exhibit high fidelity to hibernacula and shift even to nearby sites only rarely (Prior et al. 2001).

Many of the several studies that report small home ranges for colubrids did not employ methods (e.g., radio telemetry) suitable for detecting full annual or multi-annual home range size, dispersal, or other long-distance movements, so these may have yielded underestimates of home ranges or activity areas.

At least some colubrids, including medium-sized species such as garter snakes, not uncommonly move between areas up to a few kilometers apart, and several species make extensive movements of up to several kilometers, so separation distances of 1-2 km for suitable habitat are too small for medium-sized and large colubrids.

A separation distance of 10 km for suitable habitat was selected as most appropriate for snakes assigned to this Specs Group because it seems generally unlikely that two locations separated by less than 10 km of suitable habitat would represent distinct occurrences.

For the purposes of these occurrence specifications, upland habitat is regarded as unsuitable habitat for aquatic and wetland snakes. For upland snakes, shallow or patchy wetlands are treated as unsuitable habitat whereas large deepwater habitats (subjective determination) are barriers.

Inferred Minimum Extent of Habitat Use (when actual extent is unknown): .5 km
Date: 12Feb2013
Author: Hammerson, G.
Notes: Separation distance for suitable habitat was changed from 5 km to 10 km based on comments from Dale Jackson (12 Feb 2013).
Population/Occurrence Viability
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U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
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Authors/Contributors
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NatureServe Conservation Status Factors Edition Date: 28Jan2010
NatureServe Conservation Status Factors Author: Hammerson, G.
Element Ecology & Life History Edition Date: 28Jan2010
Element Ecology & Life History Author(s): Hammerson, G.

Zoological data developed by NatureServe and its network of natural heritage programs (see Local Programs) and other contributors and cooperators (see Sources).

References
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Citation for data on website including State Distribution, Watershed, and Reptile Range maps:
NatureServe. 2017. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org. (Accessed:

Citation for Bird Range Maps of North America:
Ridgely, R.S., T.F. Allnutt, T. Brooks, D.K. McNicol, D.W. Mehlman, B.E. Young, and J.R. Zook. 2003. Digital Distribution Maps of the Birds of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Bird Range Maps of North America:
"Data provided by NatureServe in collaboration with Robert Ridgely, James Zook, The Nature Conservancy - Migratory Bird Program, Conservation International - CABS, World Wildlife Fund - US, and Environment Canada - WILDSPACE."

Citation for Mammal Range Maps of North America:
Patterson, B.D., G. Ceballos, W. Sechrest, M.F. Tognelli, T. Brooks, L. Luna, P. Ortega, I. Salazar, and B.E. Young. 2003. Digital Distribution Maps of the Mammals of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Mammal Range Maps of North America:
"Data provided by NatureServe in collaboration with Bruce Patterson, Wes Sechrest, Marcelo Tognelli, Gerardo Ceballos, The Nature Conservancy-Migratory Bird Program, Conservation International-CABS, World Wildlife Fund-US, and Environment Canada-WILDSPACE."

Citation for Amphibian Range Maps of the Western Hemisphere:
IUCN, Conservation International, and NatureServe. 2004. Global Amphibian Assessment. IUCN, Conservation International, and NatureServe, Washington, DC and Arlington, Virginia, USA.

Acknowledgement Statement for Amphibian Range Maps of the Western Hemisphere:
"Data developed as part of the Global Amphibian Assessment and provided by IUCN-World Conservation Union, Conservation International and NatureServe."

NOTE: Full metadata for the Bird Range Maps of North America is available at:
http://www.natureserve.org/library/birdDistributionmapsmetadatav1.pdf.

Full metadata for the Mammal Range Maps of North America is available at:
http://www.natureserve.org/library/mammalsDistributionmetadatav1.pdf.

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