1/1
Monochrome Siskin
Pine Siskins get through cold nights by ramping up their metabolic rates—typically 40% higher than a “normal” songbird of their size. Perched on an American Plum Tree in February.

Pine Siskins get through cold nights by ramping up their metabolic rates—typically 40% higher than a “normal” songbird of their size. Perched on an American Plum Tree in February.

Copyright Howard Cheek