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	Snakes

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Garter Snakes
-by Dennis M. Ferraro Extension Educator Douglas/Sarpy Extension Unit

Garter snakes are very common in urban gardens and residential areas this time of year. These snakes are attracted to warm objects which give them the heat they need for digestion and growth. They actually prefer urban and suburban yards over farm locations.
The Garter snakes (Thamnophis radix or T. sirtalis) in Eastern Nebraska may be one of two types of species, and both are extremely variable in color. While the majority have orange, yellow, and reddish stripes along the length of it's body, some may be very dark or even cream colored. The rule of thumb in Nebraska is any snake with line or pattern running down its body length is one of our Garter snakes.
These snakes are usually 2-3 feet in length when full grown. They will sun themselves in the day and hide at night. When approached they will try to take cover. If attacked, the Garter snake will try to defend itself. They will never offensively attack any person or pet.
The Garter snakes mate in the spring in large groups, then become more secretive in the hot dry portion of the summer. In late summer and fall the snake gives birth of 12-20 young. Most of the young will not live to the next spring.
Garter snakes may frighten you, but are actually harmless. They feed on many insects as well as worms and grubs. They are beneficial to have in gardens or flow beds as they control harmful insect populations.
Total elimination of snakes in your yard is almost impossible, because they move in from surrounding areas. There are no chemical sprays, poisons or fumigants registered for snake control. While there are repellents on the market, most are ineffective in deterring snakes. Removal of debris, rocks, brush, wood piles and tall grass, which are inviting covers for snakes, may help reduce their numbers. Since Garter snakes only burrow in loose soil, some hiding places may be eliminated by packing sharp gravel and caulking around stoops and slabs.
Remember that Garter snakes are beneficial, harmless to you and your pets, and should not be killed. Snakes fear man and pets, and if left alone, they will make every attempt to escape.

Garter Snake Repellent Test
The results of my investigation clearly demonstrate that naphthalene, sulfur, or a combination of these chemicals are unable to elicit avoidance behavior in the common garter snake. The application of these substances in either the snake's home range or unfamiliar habitat failed to alter the snake's normal behavior. Garter snakes in this study clearly ignored the potential repellents. The use of these chemicals as a snake repellent should not be recommended. I have not been able to find any data that show chemical damage or adverse morhological changes to the snake' health. A habitat of dense vegetation provides garter snakes with cover against predation. These snakes utilize chemical traces to locate cover, preciously used by themselves. The presence of any foreign chemical odorant in the home range during birthing or when snakes are seeking replacement cover can be used as a cue. In this case, normally adverse odorants or repellents may act as an attractant. Homeowners applying a chemical repellent both in the snake's home range and nearby non-familiar areas such as next to a patio in hopes of curtailing snake encounters, may be creating the undesired effect. Chemicals placed in the home range may be ignored, since odor cues and related resources are already present. Over time, the snakes habituate to the chemical repellents and associate the odor of the repellents with the home range. Hence, when migrating or searching for food, these snakes may be temporarily drawn to the non-familiar location where the chemical was applied. A possible additional, unwanted outcome may occur if the landowner applies the repellent chemicals when constructing or renovating landscape as a preventative measure. Once established, the new landscape may be very attractive to displaced or migrating snakes, and the odor of the repellents may be used as a cue, especially if the new landscape is replacing home range habitat. It may be argues that if a repellent gives any results or is perceived to help, it should be a available because the use of a "pseudo-repellent" may prevent people from illegally using poison to kill snakes in an area. It is rational to place chemicals in the environment to act as a placebo and give an uninformed person temporary "peace of mind"? I believe that education appeases's the publics fears, linked with habitat modification is the most intelligent solution to the problem. When a portion of garter snakes home range is disturbed in such a way that vegetation is removed and cover habitat is destroyed, snares are no longed sighted in that area. If rock walls known to harbor large numbers of garter snakes are removed and replaced as solid cement structures, snakes migrate from that home range and my not be seen near that location for many years. In my study, it was observed that unfamiliar locations where snakes were not previously sighted, were more "sterle" looking, with less weedy vegetation and little cover. Snakes in this investigation did seek the less optimal habitat when placed in the vicinity. Using rock or lumber walls that are tight fitting with few area where snakes could find refuge may decrease snake numbers. Trimming plants, shrubs and bushes, and eliminating low and close to the ground branches lessen the favorbility of habitat. Also, removing debris and high vegetation may increase predation pressure on the snakes.

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