Bug swarms are common enough in Saskatchewan that there probably isn’t much left that surprises locals. A little over a year ago, for example, tent caterpillars took over for awhile. Two years before that, there were a lot of midges. This year, there were giant swarms of mayflies, recently filmed forming columns that resemble mini-tornadoes.

This video was shot July 13, by a woman in Courval—about 90 miles west of Regina and 80 miles from the Montana border—where an expert told the CBC that the bugs were in the midst of mating. The whole exercise, which usually occurs annually, is fleeting. Most females are dead within five minutes, and the males fly off to die alone, sometimes within hours. Millions of eggs are created, full of future mayflies doomed to repeat this appropriately violent and vital ritual.