19 December 2024
Though this willow ptarmigan (Lagopus lagopus) thinks he’s hiding his all-white plumage makes him painfully obvious in a snowless landscape.
There are three species of north country ptarmigans (Lagopus) — willow, white-tailed and rock ptarmigans — that change their plumage with the seasons in order to stay camouflaged against the ground. They’re white in winter to match the snow, brown in summer to match vegetation, and mottled as the seasons change. Their molt cycle worked well until climate change made winters shorter.
Fourteen years ago, in 2010, I blogged about the willow ptarmigan’s superior winter camouflage in Where’s Willow? and he was hard to find in the snowy landscape.
Seven years ago, in 2017, I looked again. His camouflage still worked.
But climate change is making winter is shorter. Snow cover does not begin as early as it used to the fall and it melts earlier in the spring. The ptarmigans’ molt cycle is still on the old schedule so he’s no longer camouflaged when the seasons change. You can see this rock ptarmigan easily from far away.
In 2021 ptarmigans were already in decline when scientists in British Columbia, Canada studied the effect of climate change on their native ranges in the province. Their answer is sobering in A genus at risk: Predicted current and future distribution of all three Lagopus species reveal sensitivity to climate change and efficacy of protected areas.
By 2080 all three ptarmigan species will have to move up in elevation and further north in latitude to find the climate they need to survive.
So where will the willow ptarmigan be in 2080 in BC? Three possibilities are shown below.
Willow will be in far fewer places than he is now (current range at top left).
