Speaking of Wildlife
—by Jamie Proctor
Welcome to the nineteenth column describing the residents of Speaking of Wildlife: Ontario animals that can’t be released back into the wilderness due to permanent injuries or over-habituation to humans. Today, we’ll be looking at one of the centre’s most recognizable reptiles: Kaa, the Eastern garter snake.
It’s hard not to recognize a member of the genus Thamnophis (aka, ‘garter snakes’), with their distinctive lovely yellow-and-black longitudinal stripes and the rough little keels in the center of each of their scales, making the whole snake look rugged, like an old tyre.
What’s a little more difficult is knowing what species of garter snake you’re looking at, and more difficult still is finding out what subspecies of that you’re examining. Are you looking at a Mexican garter snake, or a Mexican WANDERING garter snake? Is that Butler’s garter snake, or a ribbon snake? And if it’s a ribbon snake, is it Southern, Eastern, Northern, or Bluestripe? And of course some of these categories are disputed even among professionals, so a question as straightforward as ‘what is this snake in the garden?’ can be both very simple and very complicated depending on how specific (literally) you want to be about it.
Luckily, our friend Kaa comes pre-labelled: by species he’s a common garter snake (Thamnophis sirtalis), and by subspecies an Eastern garter snake (Thamnophis sirtalis sirtalis). This is the most common snake in Ontario and a good friend to anyone that doesn’t like earthworms (they devour them in mountains, supplemented with a good dash of frogs and a sprinkle of anything else presenting itself that it seems like a ~40-80 centimeter snake can tackle).
You can find his kin a good ways north into Ontario and all the way down to Florida, from the East coast to a bit west of Lake Superior. This generous domain is easily explained by their preferences: they’re not picky at all when it comes to habitat (Fields? Yes. Shrubs? Yes. Mixed forests? Yes. Edge habitats? Absolutely yes).
These fellows weather winter cold surprisingly well in their hidden hibernacula. They also have a particular fondness for pieces of cover they can use both as basking spots and as emergency bomb shelters in the event of something discovering them while they’re basking. They regard a certain amount of human disturbance to the landscape as just another source of pieces of cover.
Other defenses against their predators (which include a LOT of birds, mammals, and other snakes; one of the downsides of being common is you’re a reliable food source) include both freezing and hoping for their colouration to help; and secreting a foul-smelling musk (if you’ve ever tried to pick one up, you’ve probably noticed this already).
The Eastern garter snake’s bite isn’t terribly effective as an antipredator response, and they’re aware enough of this to use it more as a bluff than a true weapon, particularly against extremely big animals like humans. Though a lousy deterrent, this bite is interesting in at least one major way: garter snakes are in fact venomous, possessing a form of salivary neurotoxin.
Despite this (and the justifiable alarm most people attach to the word ‘neurotoxin’) the damage it can produce in a human is so mild and their delivery method so awkward for a human-sized target (the venom is secreted into the back of the snake’s mouth along its rearmost teeth and is gnawed into the prey manually) that it’s very difficult to tell garter snakes are venomous at all.
How difficult? Well, it took until around the turn of the millennium before word started spreading that maybe some of the occasional bruises or tenderness accompanying some garter snake bites might be from something other than physical trauma. Due to this extreme mildness, it’s still considered functionally non-venomous as far as any human of any size or age is concerned, although you may feel differently if you’re a mouse or frog.
Kaa is very old for a garter snake – he was born in captivity for educational purposes, and by the time he arrived at Speaking of Wildlife in 2014, he was young but already not a baby. He was recently rewarded for this achievement with mild dermatitis and some cataracts, but the former has been treated, and he is now back to a healthy state of being a crabby little old guy with poor eyesight.
I personally haven’t been involved a great deal with Kaa, not by choice, but by chance. I principally work at the centre, not at the shows where the snakes often travel, and the days my shifts are on don’t overlap with the scheduled snake feeding times! Outside of these rare mouse-ingesting occasions he’s quiet and low-maintenance enough that I typically don’t need to do more for him than change his water dish.
He doesn’t always welcome this minor disturbance, but is happy enough to threaten me with a not-so-subtle lunge in my general direction probably because, at his age, he’s grown to be a grumpy old man.
You can meet Kaa, and other inhabitants at Speaking of Wildlife during some of their open houses or other programming in the community. Feel free to have your birthday party there! For more information on these and on opportunities to donate, or have some SOW animals at your next event, follow Speaking of Wildlife on Facebook at https://www.facebook.com/SpeakingOfWildlife or go to the website at www.speakingofwildlife.ca.
