Alaska's great wild salmon run

The wild salmon run in Alaska is the biggest of its kind.

Each year over 50 million fish leave the Pacific Ocean and fight their way up to the headwaters of mighty river systems where they mate, spawn and die.

The young salmon make their way out to sea again and, year after year, as the fish swim back to their birthplace, fishermen are there waiting for them.

The BBC's Nick Rankin joins a commercial fishing boat at the mouth of the Egigik River to find a strictly regulated fishery and hardened crews who fight it out to get the best spots and the biggest catches.