What is a snake ball?
No metaphor: A snake ball is literally a ball of mating snakes (typically garters). Between 10 and 100 male snakes will writhe around a single female (or, sometimes, a male posing as a female) in an attempt to mate, creating a wriggling, rubbing sphere of horny reptiles. After anywhere between an hour and a day, only one male gets the chance to breed.
Where can they be seen?
Indiana Jones’s worst nightmare takes place every spring throughout North America, when garter snakes emerge from their winter hibernation to engage in romantic entanglement. Places to tread lightly: Great Smoky Mountains National Park, TN/NC; Glacier National Park, MT; Yosemite National Park, CA; basically anywhere.