A concerning decline in king salmon in the key district of Alaska's Bristol Bay -- home to the world's largest wild salmon runs -- is prompting regulators to rethink when they open up the area for fishing, sparking fears among the industry that it could eventually impact the overall catch in the entire region.

The Nushagak district, comprised of the Nushagak, Igushik and Wood River systems, has seen explosive sockeye salmon harvests since 2017.

Tim Sands, a longtime area biologist for Alaska's Department of Fish and Game (ADF&G), said that in the previous 20 years, the average harvest was around 6 million sockeye.