Plains Garter Snake

Plains Garter Snake
Thamnophis radix
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Order: Squamata
Family: Colubridae
Genus: Thamnophis
Species: T. radix
Subspecies: T. r. radix
T. r. haydeni
Binomial name
Thamnophis radix
(Baird and Girard, 1853)
Synonyms

Eutainia radix Baird & Girard, 1853
Tropidonotus sirtalis var. radix Jan, 1865
Tropidonotus ordinatus Var. radix Boulenger, 1893
Eutaenia radix Cope, 1900
Thamnophis radix Stejneger & Barbour, 1917

The Plains Garter Snake (Thamnophis radix) is a species of Garter snake native to most of the Central United States stretching as far north as Canada and as far south as Texas. It has a distinctive orange or yellow stripe that goes from its head to tail, the rest of its body is mainly a gray-green color. The snake is commonly found living near water sources such as streams and ponds, but can also be found in urban areas and vacant lots. Although the IUCN lists the species as "Least Concern", some states have given it their own special status.

Contents

Description

Physical

The Plains Garter Snake has either an orange or yellow stripe down its back and distinctive black bars on its lip.[1] The stripe normally starts at the head and continues straight down all the way to the tail tip.[2][3] There are lateral stripes located on the third and fourth scale rows and are normally a greenish yellow color.[2][3] Its belly is gray-green with small dark spots along the edges.[3] Most have distinctive light yellow spots on the top of the head.[2][3] The snake is described as medium sized and is on average around 3 feet (0.91 m).[2]

Behavior

Described as "one of the most cold-tolerant snakes", on warmer winter days it often comes out of hibernation to bask in the sun.[3] It is most active between April and late October dependent on location.[4] Mating normally takes place in April or May and birth takes place between August and October.[3] Courtship usually takes place near the communal hibernation site, and polygynous mating systems have been observed.[4] The snake's typical diet consists of earthworms, slugs and small amphibians,[3][5] including the larvae of salamanders.[4] It has also been observed eating small mammals and birds such as bank swallows and eastern meadowlarks.[5]

Habitat

The plains garter snake can be found is commonly found in meadows and prairies adjacent to water sources such as marshes, streams and ponds.[4] In built-up areas of the Chicago area it has been observed in abandoned buildings, trash heaps and vacant lots.[4] Populations in urban and suburban areas have been greatly reduced due to building activities and pesticide use.[6] Its habitat range overlaps with that of the common garter snake (Thamnophis sirtalis) in many areas, and it's thought the species may intermingle.[4][6]

Range

The snake ranges across a broad area of North America from as far north as central Alberta to as far south as Northern Texas and New Mexico. In the United States it is also found in eastern Wyoming, eastern Colorado, Minnesota, southern Wisconsin, Illinois, northwestern Indiana, Oklahoma, and the northern half of Missouri.[7] In Canada the species is also found Manitoba.[7] A small population is also in Ohio.[4][7] It can be found at elevations from 400 to 7,500 feet but prefer to stay under 6,000 feet.[7]

Subspecies

Formerly two subspecies of the Plains Garter Snake were widely recognized, however, most authorities have since dropped subspecies recognition. The first, Thamnophis radix radix, was commonly referred to as the Eastern plains garter snake, while Thamnophis radix haydeni (Kennicott 1860) was considered the Western subspecies. However, the distinction between the two is weak, partly based on the number of scales and partly on slight coloration differences, with the T. r. haydeni said to have cleaner markings and more ventral and neck scales. As the two subspecies share the same habitat in many regions of the United States, further complicated by their strikingly similar appearance, many now do not recognize the two subspecies.

Conservation

The Plains Garter Snake is listed as Least Concern (IUCN 3.1) by the IUCN Red List due to the snakes ability modify its habitat, wide distribution and presumed large population.[7] However the snake is considered to be "Endangered" in Ohio and is on a state list of endangered species.[4][8] In Wisconsin it is a species of special concern.[9]

References

  1. ^ Conant, Robert; Robert Stebbins, Joseph Collins (1999). Roger Tory Peterson. ed. Peterson First Guide to Reptiles and Amphibians. Houghton Mifflin Harcourt. ISBN 9780395971956. http://books.google.com/books?id=epHJE6NL3j8C&pg=PA100&dq=Plains+Garter+Snake&client=firefox-a&cd=1#v=onepage&q=Plains%20Garter%20Snake&f=false. 
  2. ^ a b c d Breckenridge, John (1944). Reptiles and amphibians of Minnesota. U of Minnesota Press. ISBN 0816605734. http://books.google.com/books?id=kC2tz69r1DEC&pg=PA142&dq=Plains+Garter+Snake&client=firefox-a&cd=4#v=onepage&q=Plains%20Garter%20Snake&f=false. 
  3. ^ a b c d e f g "Thamnophis radix -- Plains Gartersnake". Illinois Natural History Survey. University of Illinois. http://www.inhs.illinois.edu/animals_plants/herps/species/th_radix.html. Retrieved 8 February 2010. 
  4. ^ a b c d e f g h Rossman, Douglas; Neil Ford, Richard Seigel (1996). The garter snakes: evolution and ecology. University of Oklahoma Press. pp. 235–241url=http://books.google.com/books?id=n2rW7E8_uJoC&pg=PA235&dq=Thamnophis+radix&lr=&as_drrb_is=q&as_minm_is=0&as_miny_is=&as_maxm_is=0&as_maxy_is=&as_brr=3&client=firefox-a&cd=5#v=onepage&q=Thamnophis%20radix&f=false. ISBN 0806128208. 
  5. ^ a b Dewey, Tanya. "Thamnophis radix (plains garter snake)". University of Michigan Museum of Zoology. University of Michigan. http://animaldiversity.ummz.umich.edu/site/accounts/information/Thamnophis_radix.html. Retrieved 8 February 2010. 
  6. ^ a b Degenhardt, William; Charles Painter, Andrew Price (2005). Amphibians and Reptiles of New Mexico. UNM Press. pp. 324–325. ISBN 0826338119. http://books.google.com/books?id=r-Liq4O4udsC&pg=PA325&dq=Thamnophis+radix+habitat&lr=&as_brr=3&client=firefox-a&cd=1#v=onepage&q=Thamnophis%20radix%20habitat&f=false. 
  7. ^ a b c d e "Thamnophis radix". Hammerson, G.A.. IUCN Red List. http://www.iucnredlist.org/apps/redlist/details/63988/0. Retrieved 8 February 2010. 
  8. ^ "Ohio's Endangered Species". Ohio DNR. http://www.dnr.state.oh.us/wildlife/Home/resources/mgtplans/endangered/tabid/6005/Default.aspx. Retrieved 8 February 2010. 
  9. ^ "Plains Gartersnake (Thamnophis radix) Endangered Resources Program Species Information". Wisconsin DNR. http://www.dnr.state.wi.us/org/land/er/biodiversity/index.asp?mode=info&Grp=49&SpecCode=ARADB36100. Retrieved 8 February 2010.