Every year, millions of salmon battle their way up British Columbia’s Adams River in a spectacular display of life and death. And as the salmon run, the locals celebrate and the tourists flock.

It’s a fight for their lives. Picked off by bears, coyotes, eagles and fishermen, it’s no easy feat for the sockeye salmon of British Columbia to return to their place of birth to spawn—in fact, it’s a 460-kilometer upstream battle back to the Adams River at the end of their four-year life cycle.

And for locals, it’s one of the most important events of the year.

Every fall, around mid-October, the Adams River in the Shuswap region, turns red with the migrating salmon. Every fourth year is a dominant year of the cycle, and 2018 is set to see a record number of sockeye—an estimated 25 million—make the run, all the way from the Pacific Ocean to interior British Columbia.