A slithering carpet of 75,000 snakes in a space the size of a living room. Itís hard to imagine wanting to get close to such a scene, but at this time every year, visitors from around the world attend the unusual display in the remote hamlet of Narcisse, Manitoba.

Thousands of red-sided garter snakes awaken from an eight-month nap in their subterranean limestone lairs. They tumble about the craggy landscape in tangled knots with a singular focus: reproduction.

The males pour out of the dens first and wait for the females to slowly trickle out over the course of a few weeks. ďOnce she gets up off the floor, sheís sort of swarmed by all of them,Ē said Doug Collicutt, a local biologist.

A female secretes pheromones, luring dozens to hundreds of males that try to court her by rubbing their chins along her back and flicking their tongues. At times, the ratio of males to females is 10,000 to 1.

She ultimately decides when she is ready to mate by a mysterious mechanism called cryptic female choice. The closest male wins and leaves a stinky plug inside her that tells others to back off. She can wait a couple days for the plug to dissolve and mate with another snake, or she can slither into the swamps to feed and give live birth to her babies in August.

A female can store sperm until sheís healthy enough to reproduce, said Bob Mason, a biologist at Oregon State University. He documented a female snake who gave birth seven years after mating.