If you go out walking today, walk beside the ditches. If you’ve paid all your taxes and been good to the elderly, you may be blessed with the sight of a bunch of little male garter snakes entwining a much larger and very sore female. You’ve found a garter snake mating ball!
Like most people, you’ve always wondered about the reproductive happenings of snakes and other seemingly bitless animals, but were afraid to bring it up in polite company. Luckily, I am not polite company.
First off, snakes are not bitless; like most tetrapods their bits are usually internal. They have a cloaca, which is a hub shoot for the poop/pee/lovin’/baby/musk shoot(s), at the base of their tail. If you’ve ever picked up a snake, you probably have been smeared with some nasty smelling gunk and know where this is. In garter snakes and most other male squamates, the cloaca also holds the hemipenes: which is basically a forked wang.
Garter snakes, being one of the most cold-tolerant, are the first snakes to come out when it starts warming up. They usually share winter dens, ranging from just a few individuals to several thousands. The males are first, and they usually hang around and wait for the females to emerge. The females emit pheromones which attract the nearest males, and it’s on. Really on. The males all swarm around the female, each one trying desperately to align themselves just right before any other male can. Around my house the biggest number I’ve seen is five males to a female. Elsewhere, these mating balls get even bigger than that. It’s like an ocean of snakes.
The lucky male that gets everything in place inserts one hemipenis, and does the deed. Sometimes he leaves a copulatory plug, which is a supergross secretion that hardens and prevents further mating from taking place. The female possesses the ability to store the sperm for when she needs it, and can keep it there for five years. They usually give birth to live young from July to October.
Now you know how garter snakes do it. I hope you are fulfilled, yet unaroused.