Male tarantulas are moving and wooing their way across Colorado : NPR

Each year, male brown tarantula trek across Colorado to look for ladies.

From mid-September to mid-October, they leave the safety of their burrows to go on journeys that will take interesting turns as they face rejection, predators and fatigue.

Why they're on the move

Cara Shillington, a biology professor at Eastern Michigan University, doesn't consider the trek a migration because "this is not a one-way movement from one location to a different location."

Arachnid aficionados say although male tarantulas spend most of their lives in their underground burrows, they leave them to find female tarantulas once they reach sexual maturity.

"They get to this nice, reflective color on their exoskeleton. They'll look a lot prettier," said Chandler Peters, an entomology keeper at the Arizona-So