The Northern saw-whet owl is a small owl found in the northern hemisphere that is 17-21.9 cm long with a 45.9-56.3 cm wingspan and weighs 75-110 grams. It eats rodents and nests in old woodpecker cavities, laying 3-7 eggs about 30 x 25 mm in size. Bigger owls prey on the Northern saw-whet owl, while it lives in forests across the northern hemisphere.