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Storeria dekayi
Brown Snake


By Leslie Seaholm

Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Reptilia
Order: Squamata
Family: Colubridae
Genus: Storeria
Species: Storeria dekayi
Members of this Species

Geographic Range

Storeria dekayi is an abundant snake that is widely distributed.

It is found in southern Canada, in the United States east of the Rocky Mountains, and in the northern portions of Mexico (Ditmars 1936).

Biogeographic Regions
nearctic (Native )

Habitat

This is a snake that is still fairly abundant. The reason for this can be mostly attributed to its smaller size and broad habitat preferences. Brown snakes are typically found hiding among loose stones or flat rocks that are found in the wild and in large cities (Ditmars 1936). These snakes will spend most of their life under the ground, but during heavy rains they will sometimes go out into the open (Harding 1997). This usually occurs in October - November and during late March - April when they are moving to or from hibernation spots (Harding 1997). Sometimes these hibernation spots will be shared with other snakes such as garter snakes, red-bellied snakes, and smooth green snakes (Harding 1997). (Ditmars, 1936; Harding, 1997)

Habitat Regions
temperate ; terrestrial

Terrestrial Biomes
chaparral ; forest ; scrub forest

Wetlands
marsh

Other Habitat Features
urban ; suburban

Physical Description

Range length
23.0 to 52.7 cm
(9.06 to 20.75 in)

The brown snake is a fairly small snake that rarely exceeds 15 inches in length (Ditmars 1936). It has a stout body with large eyes and heavily keeled scales (Collins 1987). Storeria dekayi is typically found to be a grayish brown color with a lighter streak on its back that is bordered on each side with black dots. The belly of the brown snake is a pinkish white color. Typically there are 17 scale rows at midbody and the anal plate is divided (Harding 1997). Males and females generally look the same, but males tend to have longer tails (Harding 1997). There are several other subspecies of Storeria dekayi that look slightly different, but there is no textual evidence of any seasonal variation. Young brown snakes are small, about 3 1/2 inches long on average and are black or dark gray in color (Simon 1979). A distinguishing characteristic of the young is a light grayish white colored ring found around the neck. At this age they are sometimes confused with ring necked snakes, but are distinguished by their keeled scales (Ditmars 1936). (Collins, 1987; Ditmars, 1936; Simon, 1979)

Other Physical Features
ectothermic ; heterothermic ; bilateral symmetry

Sexual Dimorphism
female larger; sexes shaped differently

Reproduction

Mating System
polygynous

Breeding interval
Brown Snakes breed once yearly.

Breeding season
Brown Snakes give birth to their young in late summer.

Range number of offspring
3.0 to 41.0

Average age at sexual or reproductive maturity (female)
2.0 years

Average age at sexual or reproductive maturity (female)
Sex: female

730 days
[External Source: AnAge]

Average age at sexual or reproductive maturity (male)
2.0 years

Average age at sexual or reproductive maturity (male)
Sex: male

730 days
[External Source: AnAge]

The brown snake is viviparous, and gives birth to 12 - 20 young (Ditmars 1936). This occurs during the later parts of the summer around late July to early August (Ditmars 1936). After the young are born there is no parental care involved, but sometimes young brown snakes will stay close with the parent (Harding 1997). Brown snakes reach sexual maturity by the end of their second summer, usually by this time they have doubled in

length (Harding 1997).

Key Reproductive Features
iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); ovoviviparous

The young are nourished within their mother's body while they develop. Once the young are born there is no further parental care, but sometimes young Brown Snakes will stay near their mother.

Parental Investment
precocial ; female parental care

Lifespan/Longevity

Range lifespan
Status: captivity

7.0 (high) years

Average lifespan
Status: captivity

7 years
[External Source: AnAge]

Little is known of Brown Snake lifespans in the wild, but a captive individual lived to be 7 years old. Wild Brown Snakes may approach this lifespan in the wild, though many young die before becoming mature.

Behavior

Breeding in Storeria dekayi starts out with the male following a female that leaves a pheromone trail (Harding 1997). The brown snake (male) uses his tongue to identify a potential mate, making sure it is a female, the male then inserts a hemipenis into the female's cloaca after making various courting movements (Harding 1997). Brown snakes are typically harmless nonvenemous snakes. Some of their predators are large frogs and toads, larger snakes, crows, hawks, shrews, weasels, certain bird species, and domestic

cats and dogs (Harding 1997). When these snakes do feel threatened they will flatten their bodies out to appear larger and place their bodies in an aggressive posture, and they will even release a musky smelling fluid from the cloaca (Harding 1997).

Key Behaviors
nocturnal ; motile ; solitary

Communication and Perception

Brown Snakes communicate with each other primarily through touch and smell. They use their forked tongues to collect chemicals from the air and insert these forks into a special organ in the roof of their mouth, which interprets these chemical signals. Because Brown Snakes hunt mostly underground and at night, they probably use almost exclusively their sense of smell to find prey. Snakes are also sensitive to vibrations and have reasonably good vision.

Food Habits

Brown snakes feed largely on earthworms, snails, and slugs, but will also eat small salamanders, soft-bodied grubs, and beetles. They have specialized teeth and jaws that allow them to pull snails out of their shells and eat them. (Ditmars, 1936; Harding, 1997)

Primary Diet
carnivore (Molluscivore , Vermivore)

Animal Foods
amphibians; insects; terrestrial non-insect arthropods; mollusks; terrestrial worms

Predation

Known Predators


Brown snakes are eaten by large frogs and toads, larger snakes, American crows, hawks, shrews, weasels, blue jays, and domestic cats. When these snakes feel threatened they flatten their bodies to appear larger and place their bodies in an aggressive posture. They will also smear their attacker with a foul-smelling musk that they exude from their cloaca.

Ecosystem Roles

Brown Snakes help to control populations of snails, slugs, and earthworms. They also serve as a valuable food supply for their predators.

Economic Importance for Humans: Positive

These little snakes may benefit humans by controlling slug damage in gardens (Harding 1997). No other known benefits have been found.

Positive Impacts
controls pest population

Conservation Status

IUCN Red List of Threatened Species [Link]
Least Concern
More Information

US Federal List [Link]
No special status

CITES [Link]
No special status

State of Michigan List [Link]
No special status

This is a fairly common species, but it does face threats such as exposure to pollution and destruction of rural and urban habitats (Harding 1997). No known efforts are being made to ensure viable populations for the future.

For More Information

Find Storeria dekayi information at

Contributors

Leslie Seaholm (author), Michigan State University, James Harding (editor), Michigan State University, , 205 Museum, Michigan State University, East Lansing, MI 48824.

References

Collins, J. 1987. Snakes Ecology and Evolutionary Biology. New York: Macmillan Publishing Company.

Ditmars, R. 1936. The Reptiles of North America. New York: Doubleday, Doran and Company, Inc..

Harding, J. 1997. Amphibians and Reptiles of the Great Lakes Region. Ann Arbor: The University of Michigan Press.

Simon, H. 1979. Easy Classification Guide to North American Snakes. New York: Dodd, Mead, and Company.

To cite this page: Seaholm, L. 2000. "Storeria dekayi" (On-line), Animal Diversity Web. Accessed May 23, 2012 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Storeria_dekayi.html

Disclaimer: The Animal Diversity Web is an educational resource written largely by and for college students. ADW doesn't cover all species in the world, nor does it include all the latest scientific information about organisms we describe. Though we edit our accounts for accuracy, we cannot guarantee all information in those accounts. While ADW staff and contributors provide references to books and websites that we believe are reputable, we cannot necessarily endorse the contents of references beyond our control.

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