One from the archives, taken in Saskatchewan, Canada in the 1990s. The Pine Siskin (Spinus pinus) looks fluffed up against the cold but it will get a lot colder in the winter.
Pine Siskins can survive very low temperatures. Their metabolic rate is 40% higher than typical for songbirds of their size. In extreme cold they can increase their metabolic rate up to five times normal.
This is my favourite Pine Siskin shot from Saskatchewan although I can’t explain why. The bird isn’t doing anything and is partially obscured by a branch. Maybe it’s the colour combination of the bird and the autumn leaves.