Pattern and Defense: Garter Snakes are so called due to the stripes down their back which resemble garters, used for holding socks up. These stripes are used by the snake as a method of escaping predators. Longitudinal stripes can give the illusion that the animal is moving much slower than it actually is. This is beneficial as a predator would attack where it thinks the snake is rather than where it is going, causing it to miss or be redirected to the tail which lacks major organs. This method of using stripes to avoid predation is known as the “redirection hypothesis” and is believed to be used by many snake and lizard species.
Eastern garter snakes, among other species of snake, do not chase people. There are myths of snakes such as rattlesnakes, cottonmouths and even garter snakes being aggressive and chasing. These are much more likely to be one interpretation of their defensive strategy. If threatened, most snakes will escape as fast as they can, when they’re cold however, they don’t have enough energy to quickly get away and have to find other methods of defense. Garter snakes that have been in the cold or have just eaten, for example, are more likely to puff themselves up with air to look bigger and bluff strike, to scare a predator away. Sometimes, these bluff strikes move their body closer to the potential predator giving the appearance that they are chasing someone without the snake actively pursuing. This interpretation of their defense has sadly led to the persecution of these ecologically important animals with people often killing snakes out of fear. |
Colour and Morphs: Melanistic Populations of melanistic garters exist in much of southern Ontario. The garter snakes on Pelee island represent one of the largest populations with roughly one out of three snakes being melanistic. Melanistic is a colour mutation where individuals produce large amounts of melanin pigment resulting in almost all black bodies. Some individuals will have some remnants of a stripe down their back while others may have brown on their face. All however, have a white face or lower jaw leading them to be misidentified as ratsnakes or racers by some. Because dark colours absorb more heat, melanistic individuals have an advantage over their striped counterparts. When basking, melanistic garter snakes have been found to be 1.3°C warmer. While this difference in temperature doesn’t sound huge, it’s a big deal for snakes, especially those full of babies as the warmth helps speed up gestation. While the dark colouration helps these snakes absorb heat, it also makes them more susceptible to predators as they can more easily be seen against the forest floor.
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Colour and Morphs: Flame Red eastern garter snakes occur commonly in various populations throughout Ontario, especially those in Northern portion of the province. It’s been suggested that this colouration is to mimic the vibrant venomous snakes of the tropics. Many of the birds that would prey upon garter snakes up north, migrate long distances every winter to the tropics. These areas have a great diversity of snakes that warn predators of their venom through the use of bright colours. Knowing not to prey upon brightly coloured snakes, the birds come back to Canada and are reluctant to prey upon garter snakes with bright red colouration. This better allows the erythristic red individuals to survive longer, allowing them more opportunities to pass on their red genes to future generations.
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Traditional Ecological Knowledge: Garter snakes are usually some of the first snakes to emerge in spring, appearing even when there is still snow on the ground. Snakes slithering In the snow resemble the game; 𝘎𝘰𝘰𝘯𝘪𝘪𝘬𝘢𝘢-𝘎𝘪𝘯𝘦𝘣𝘪𝘨 𝘈𝘵𝘢𝘢𝘥𝘪𝘪𝘸𝘪𝘯 or “snow snake game”, played by a number of Indigenous Peoples in North America such as the Onondaga and Oneida, among others (Connors, 2016). This game would involve many different communities coming together and act as a medicine to reinforce bonds between both communities and individuals (Cornelius, 2009). The game is played with wooden sticks carved to look like snakes. These are thrown down a track carved into the snow with the goal of trying to go the furthest. The “snakes” were often made of poplar, maple, hickory or ash depending on what’s available (OnondagaNation.org, 2018). Each snake has a heavier, upturned front and is tapered towards the back. This weight distribution would often cause the stick to move like a snake when thrown, lending it the name of snow snake (Dana, 2014).
Sources:
Connors, Colin, producer. Snow Snake - Ojibwe Winter Games 2015. , YouTube, 2016, www.youtube.com/watch?app=desktop&v=piQx9v1gVMY&fbclid=IwAR1-v0yYhuzbRQoHklltnOe9ZS06zLZwZnT7OiiYSj_EkXZ0qEk9nH58wWY. Accessed 7 Dec. 2021. Cornelius, Randy, narrator. Snow Snake in Oneida WI 2009. , Oneida Digital Media, 2009, www.youtube.com/watch?app=desktop&v=rfn5LE88JPc&fbclid=IwAR2h4Z61DU3y_NG_U0yciyhF2JVAThgXZiYzVG_7VvZVv-vTk0e3nhvwCiM. Accessed 7 Dec. 2021. "Eastern Gartersnake." Ontario Nature, 2021, ontarionature.org/programs/community-science/reptile-amphibian-atlas/eastern-gartersnake/. Accessed 7 Dec. 2021. Gibson, A R., and J B. Falls. "Thermal Biology of the Common Garter Snake Thamnophis sirtalis (L.)." Springer Link, Oecologia, Oct. 1979, link.springer.com/article/10.1007/BF00346675?fbclid=IwAR2RiYcHQphqWQ1pmppAS-cb469QfH9Qos5_kMXQgnjWpnXEgbBlo1xDgYo. Accessed 7 Dec. 2021. Mills, Peter B. "Better Red than Dead?" Peterbmills.com, The Canadian Herpetologist, 2017, www.peterbmills.com/uploads/4/9/4/5/49458183/better_red_than_dead.pdf?fbclid=IwAR1vzvPFjrdyPUNJ7tEzLdlG2yMcOt75PKQQ33L9ojf-81WLJv_2AQ_n5i0. Accessed 7 Dec. 2021. Murali, Gopal, and Ullasa kodandaramaiah. "Deceived by Stripes: Conspicuous Patterning on Vital Anterior Body Parts can Redirect Predatory Strikes to Expendable Posterior Organs." National Center for Biotechnology Information, The Royal Society Publishing, 8 June 2016, www.ncbi.nlm.nih.gov/pmc/articles/PMC4929900/?fbclid=IwAR3fEurPJskmo1WIqzHrSDP_UqKdQAwcPutbw5SerAcu1mnyjlKopebQ430. Accessed 7 Dec. 2021. Passek, K M., and J C. Gillingham. "Thermal Influence on Defensive Behaviours of the Eastern Garter Snake, Thamnophis sirtalis." National Library of Medicine, Sept. 1997, pubmed.ncbi.nlm.nih.gov/9299047/. Accessed 7 Dec. 2021. Rowell, Jeffrey C. The Snakes of Ontario: Natural History, Distribution and Status. Winnipeg, Art Bookbindery, 2012. |