The winter distribution of an Arctic goose has shifted northwards as climate has warmed over the last 40 years, with birds once wintering in Mexico now staying in Alaska.
Studies have shown that, until recently, nearly the entire population (90 per cent) of Pacific Black Brant spent the winter in Mexico. Now as many as to 30 per cent are choosing to spend their winters in Alaska instead. Fewer than 3,000 geese were detected wintering in Alaska before 1977, and this has now jumped to as many as 40,000 birds.
Lees meer: Birdwatch
Studies have shown that, until recently, nearly the entire population (90 per cent) of Pacific Black Brant spent the winter in Mexico. Now as many as to 30 per cent are choosing to spend their winters in Alaska instead. Fewer than 3,000 geese were detected wintering in Alaska before 1977, and this has now jumped to as many as 40,000 birds.
Lees meer: Birdwatch
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