Bison - Sounds Wild
Wood Bison 2021

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Transcript

An orange airplane flies over the broad green expanse of Southwest Alaska near the Lower Yukon River in late June of 2021. The plane is the Fish and Game de Havilland Beaver, equipped with an ultra-high-definition digital camera for aerial photocensus surveys. These surveys are most often conducted on Alaska's caribou herds, but this June, Alaska's four herds of plains bison have been surveyed. Today, it's photographing Alaska's wood bison, in the Lower Innoko-Yukon Rivers herd, near Shageluk. The photographs enable biologists to count individual bison, and identify the smaller, reddish brown calves.

Calving is at an all-time high, with 26 calves born in the spring of 2021. Overall, the herd has grown by more than 10% in the last year, to a total of 103 bison. Since the release of the wood bison herd in 2015, it has grown in four out of six years. The two years of decline were likely due to ice layers forming in the snowpack from winter rainstorms and warming events.

Bison are good at foraging in deep, soft snow, but ice layers in the snowpack make this more difficult. In late winter of 2021, there was deep snow, but no ice layers. With any luck, there will not be rain-on-snow events in coming years and this herd will have a chance to grow even more.