Nature’s World:  NORTHERN PYGMY-OWL

by Susan Tweit

Recently, our backyard hosted an unusual avian visitor: a northern pygmy-owl. In mid-afternoon, I looked out my office window and saw a small gnome-like shape perched on a branch of our lilac hedge.

The bird’s large, rounded head, upright posture, and neck-less silhouette said “owl,” but our backyard, just a block from downtown Salida, is not great owl habitat. So I was very surprised to look through my binoculars and see a northern pygmy-owl.

Northern pygmy-owls are small, just seven inches from beak to tail tip, and lack the conspicuous feathered ear tufts of typical owls. The smooth, gray-brown plumage covering their back and head is sprinkled with white dots; their white chests are streaked vertically with heavy, dark lines.

All of that dotting and streaking would seem to make the bird stand out, but in fact, perched in the dappled shade of open mountain woodlands, their favored habitat, the bold patterning blends right into the light and shadow.

What does make a pygmy-owl stand out, at least when seen through binoculars, are the start-ling “eyespots” on the back of their head. Two black half-moons topped by white eyebrow lines look just like a pair of owl eyes—until the bird swivels its head and the real eyes stare at you.

Despite their diminutive size, northern pygmy-owls are fierce predators. More active in daylight than most owls, they fly rapidly and often low to the ground in pursuit of prey, including voles and mice, insects, small birds, and even lizards.

A pygmy-owl snatches its prey with its powerful feet, and carries it back to its perch to eat. There, the owl tears into its meal, crushing the small bones with the clenching muscles in its feet so that the owl can swallow whole chunks.

Like all birds, owls lack teeth. Thus, they do what our mothers told us not to do: swallow their food whole. Owls digest the soft parts, and regurgitate the bones, feathers, and other in-edibles in tidy pellets.

The northern pygmy-owl in our lilac hedge had caught a house sparrow from the flock that haunts our feeders. The owl sat on a prominent branch with the house sparrow carcass held firmly in its claws, tearing off a chunk and swallowing, and then sitting quietly, dinner in hand, and looking around.

Unlike our native bird species, house sparrows, native to Britain and adjacent Europe where there are no small bird-catching owls, may not immediately recognize pygmy-owls as predators. In fact, the flock initially perched in the hedge next to the owl, and then suddenly flew off in a flurry of terrified house sparrow wings.)

Northern pygmy-owls are often “mobbed” by flocks of songbirds, which perch nearby, fuss in loud voices, attempting to scare the owl away.

Those startling eyespots may serve as protection from larger predators. The pretend eyes could trick a predator into diving at the back of the pygmy-owl’s head, thus allowing the small owl to escape without injury.

Northern pygmy-owls inhabit the mountains of western North and Central America from British Columbia to Guatemala. They are birds of open mountain forests; in Colorado, they prefer ponderosa and piñon pine woodlands, aspen groves, and riparian forests along rivers and streams.

Male northern pygmy-owls begin defending nesting territories as early as February in Colorado, and by late March, are courting their intended mates with aerial chases and gifts of food.

These petite owls nest in tree cavities, either natural openings or abandoned woodpecker holes. After a female lays eggs, she remains in the cavity through the 28-day incubation period; after the eggs hatch, both parents hunt to feed the growing young.

Young northern pygmy-owls fly from the nest when they are about a month old. They stay with their parents through their first summer, and then wander off to find their own territories.

Northern pygmy-owls move downhill in fall and winter, following the availability of prey. That, plus the drought, which has cut the availability of food, combined with the noisy and oblivious flock of house sparrows at our feeders, probably explains our unusual avian visitor. 

No one knows how many northern pygmy-owls live in Colorado, because records of these normally reclusive owls are rare. Hence our delight to see a northern pygmy-owl in our downtown backyard!

   © 2003 Susan J. Tweit