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This site was created by students in the herpetology class at Towson University. Site last updated: 05/21/07. Acknowledgements: Herb Harris - Range Maps; Mark Tegges - Photography; Dan Lapascha & Gigi Forester - TU Herpetology Logo |
Eastern garter snake (Thamnophis sirtalis)
The Eastern garter snake is one of the most commonly encountered snakes in Maryland. This is a medium-bodied snake ranging in length from 45.7 – 131.1cm with quite variable coloration and a prominent dorsal stripe and lateral stripe. The lateral stripes are confined to scale rows 2 and 3 and blotches or spots are often found in between the stripes. The dorsum is usually a dark brown to green color while the venter ranges from yellow to gray. The head is brown or black with no more than 2 small yellow spots near the parietal scales on top of the head. The dorsal scales are keeled in 19 rows, 7 upper labial scales are present which may have dark black bars and the anal plate is undivided. When handled, they often expel a musky secretion from the anal glands. Juveniles look like adults; however, their patterns are often more bold and visible. Habitat The Eastern garter snake can be found in a wide variety of habitats, including city backyards and gardens. More commonly, they are found in semi-aquatic or terrestrial habitats ranging from mixed deciduous-coniferous forests to marshes and drainage ditches. During the winter months they can often be found hibernating in communal dens. This communal type of hibernation serves 2 main purposes: reducing heat loss from the body and bringing males and females in close proximity which facilitates mate location the following spring. Breeding Sexual maturity is attained at 2 years of age. Males and females emerge from hibernation in the early spring and mating usually occurs between March and mid-May. Fall mating has also been observed, but is less common. Males locate females through chemical cues, most often using olfactory senses to trail the female until mating. Females give birth to 7-85 live young between July and September that range in length from 13-23 cm.
Distribution in Maryland
Range map adapted from Harris, 1975.
Links http://www.herpnet.net/Minnesota-Herpetology/snakes/E.GarterSnake.html http://www.dnr.state.oh.us/wildlife/Resources/reptiles/egart.htm http://www.uga.edu/srelherp/snakes/thasir.htm
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