Contia tenuisSharptail Snake

Geographic Range

The Sharp-tailed Snake (Contia tenuis) is a North American species generally found in the Sierra Nevada Mountain Range from southern California to southern British Columbia and along the Pacific Coast of California. In California, this species can be found in and along the mountains from Eureka to central San Luis Obispo, and along western slope of the Sierras in the foothills and at middle to low elevations (max altitude 2130 m (7000 ft.) (Leviton 1971; Morey 1989).

Habitat

Sharp-tailed Snakes occur in a variety of habitats, however, they are most commonly found in moist environments with an abundance of surface debris, such as twigs, roots, and leaves. The Sharp-tailed Snake is found in areas with surface moisture and it becomes active during the cool fall and winter temperatures. Because of their preference for cooler temperatures and higher moisture levels, C. tenuis is active at different times and in different microhabitats than most snakes. However, its range overlaps that of the Ring-neck Snake(Diadophis punctatus), and they can be found under the same cover at times. The Sharp-tailed Snake can be found mainly in wooded areas or near intermittent streams (Leviton 1971; Morey 1989; Basey 1976).

Physical Description

At maximum, the Sharp-tailed Snake may grow to a length of 19 inches (47.5cm), but most adults are about 12 inches (30cm) long. Shiny reddish-brown or gray scales above and a whitish line down the side characterize C. tenuis. An alternating pattern of black, pale greenish, gray, or cream bars can be found on its belly, and its smooth scales come in 15 rows around the body. The most distinguishing characteristic of this snake is the sharp spine-like scale at the tip of its tail. Although the function of this scale is not completely understood, it is thought to be used as an anchor during struggles with its victims (Basey 1976; Leviton 1971).

Reproduction

Habitat requirements for reproduction are unknown. Mating

of the Sharp-tailed Snake occurs in spring and in the

summer it lays 3-8 eggs. There is evidence that indicates that on occasion, eggs are laid in communal nest sites. Hatching occurs in the fall, and the egg clutches can be found in 7 to 15cm (2.8 to 6 in.) of soil, among grass roots and deep in rock outcrops (Morey 1989; Basey 1976; Nussbaum et al. 1983).

Behavior

The Sharp-tailed Snake is a small, secretive, diurnal species, which moves around during the rainy season, from October through April. Even during its most active periods, C. tenuis tends to hide underneath rocks or any other cover it may find such as, logs, bark, twigs, or any cover in or around wooded areas. During the end of spring and through the summer months, they take refuge in burrows, and remain there until the moistened ground, from early rains, attracts them to the surface. There is no evidence of territoriality and individuals often aggregate at favorable sites. Several individuals can be found under a single small, flat rock. Predators include Steller's Jays and other diurnal birds, small mammals, and other snakes. A Brook trout has been seen capturing a Sharp-tailed Snake, which appears to be the only documented record of a fish eating a snake (Mattison 1995; Leviton 1971; Morey 1989; Basey 1976).

Food Habits

Slugs are the primary food of the Sharp-tailed Snake.

Although there are no observations of C. tenuis preying on

any other species, it is suggested that snails and small

plethodontid salamanders may also be taken. The Sharp-tailed Snake may use the spine on its tail to brace itself while capturing its prey. Long, needle-like teeth on its mandibles are noted as an adaptation to gripping and eating slugs (Mattison 1995; Stebbins 1954; Greene 1997).

Economic Importance for Humans: Positive

C. tenuis has no major economic importance, but may be adapting to live around rural and suburban gardens, where they feed on abundant non-native slug species (Morey 1989).

Economic Importance for Humans: Negative

None.

Conservation Status

Contributors

Jared Rider (author), Fresno City College, Carl Johansson (editor), Fresno City College.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

chaparral

Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

References

Basey, H. 1976. Discovering Sierra Reptiles and Amphibians. California: Yosemite Natural History Association.

Greene, H. 1997. Snakes: The Evolution of Mystery in Nature. Berkeley and Los Angeles, California: University of California Press.

Leviton, A. 1971. Reptiles and Amphibians of North America. New York: Doubleday & Company, Inc..

Mattison, C. 1995. The Encyclopedia of Snakes. New York: Facts on File, Inc..

Morey, S. "California Wildlife Habitat Relationships System: R049, Sharp-tailed Snake, Contia tenuis" (On-line). Accessed 5 April 2001 at http://www.dfg.ca.gov/whdab/R049.html.

Nussbaum, R., E. Brodie, R. Storm. 1983. Amphibians and Reptiles of the Pacific Northwest. University Press of Idaho.

Stebbins, R. 1954. Amphibians and Reptiles of Western North America. New York: McGraw-Hill.