On quiet nights in March you’ll hear but not see these small-bodied, big-headed owls. They produce shrill cries, audible from hundreds of metres away, that sound like a saw being sharpened on stone—skreigh-aw, skreigh-aw, skreigh-aw—as well as a rapid toot-toot-toot call. During breeding season, males can call for hours.
Saw-whets are one of North America’s smallest owls, no bigger than a robin, and only weighing about 80 grams—that’s less than a fifth of a pound. Their small size makes them prey targets for larger owls and other raptors. But their mottled brown coat and ability to stay motionless when approached or threatened makes them excellent at camouflage. They also use this to their advantage when hunting, usually at dawn or dusk. They sit on low perches, waiting for mice and voles to scurry by, then drop down to grab the unsuspecting prey.