|Image from Idaho Birding Trail|
As far as diet is concerned, the Northern Saw-Whet Owl really loves its rodents. Typically 70% to 80% of their diet consists of mice and voles, with the rest being filled in my insects, spiders, other birds, and even marine crustaceans. Larger prey, including mice, is consumed in two different meals, as it is possible for the owls to choke while attempting to consume their prey whole. Hunting takes place at night with help from night vision and superb hearing. They stake out their prey from low perches (6-12 feet above the ground) before silently swooping in.
Northern Saw-Whet Owls are monogamous, but not for life. Males attract females with their lovely singing voices, and will take them to the nest sites they have selected before doing a little head bobbing dance. Nests are built in tree cavities, and the female watches over the eggs while the male performs all of the hunting. Eggs hatch after 3-4 weeks, and fledging takes place 4-5 weeks after that. Captive individuals have lived 8 years, but the life expectancy in the wild is unknown. They are preyed upon by larger owls, other birds of prey, and larger (to them anyway) mammals.
Thanks to John for the suggestion!