Walk in the woods around Missoula and in western Montana and you may hear the distinct hoo-hoo of a Great Horned, Great Grey or Barred Owl to name a few. Chances of finding owls are not that great when looking for them, but after hearing an owl, you will know where to look. This time of year, male owls have begun their search for mates to begin breeding. Great Horned Owls are the first birds to start families, beginning in February. They start early because it takes them a relatively long time (in bird terms) to hatch the brood. Females lay between two to four eggs, but they must incubate them for 30 to 35 days before they hatch. Robins and chickadees take half that time.
Different species of owls make different sounds; this wide range of calls aids owls in finding mates or announcing their presence to potential competitors. The distinct calls also aid ornithologists and birders in locating these birds and recognizing species.
In March and early April, the male Barred Owl’s call asks the question, ”Who cooks for you? Who cooks for you all?” It is time for them to begin the all important mating ritual.
The male Screech Owl’s most common call is an eerie, mellow, muted trill consisting of about many notes and lasting about three seconds. The Screech Owl, however, is perhaps better known for its shrill, descending whinny used to defend its territory.
Western Montana has at least 15 species of owls. All are in the Strigidae family except the Barn Owl or Tyto alba which is in the Tytonidae family. The two families of owl, typical and barnyard, are also found in a variety of habitats worldwide.
Montana’s largest by length is the Great Grey Owl at about 27 inches. The smallest in Montana by length is the Flammulated Owl at about 6 3/4 inches. Flammulated Owls are one of the smallest owls in North America; only Elf Owls are smaller.
Year-round Montana residents are the Barn Owl, Barred Owl, Boreal Owl, Great Gray Owl – Species of Concern, Great Horned Owl, Northern Pygmy-Owl, Northern Saw-whet Owl, Long-eared Owl, Short-eared Owl – Potential Species of Concern, andWestern Screech-Owl – Potential Species of Concern.
Montana winter residents are the Snowy Owl and the Northern Hawk Owl- Potential Species of Concern which actually is evidenced as breeding and year-round resident in and around Glacier National Park.
Summer (and breeding) resident is the Flammulated Owl- Species of Concern. They arrive back in the Big Sky state in late April and early May.
Found only east of the mountains in Montana plains are the summer resident Burrowing Owl-Species of Concern and year-round resident Eastern Screech-Owl- Potential Species of Concern.
Owls have large forward-facing eyes and ear-holes, a hawk-like beak, a flat face, and usually a conspicuous circle of feathers around each eye called a facial disc. The feathers of this disc can be adjusted to help the owl sharply focus on sounds that come from varying distances. The eyes of most birds of prey are positioned on the sides of their heads, but the stereoscopic nature of the owl’sforward-facing eyes gives them the greater sense of depth perception necessary for low-light hunting. Although owls have binocular vision, like all birds their large eyes are fixed in their sockets. They must turn their entire head to change their view. Owls can rotate their head and neck up to 270 degrees to both sides.
Most owls are nocturnal meaning they are most active and hunt for food at night. They are well equipped with special adaptations that allow them to find prey in the dark. Large eyes collect all available light, even if it’s only the light of the moon and their sensitive ears can hear the tiniest scampering sound of prey. Combine those tools with the soft wings that make them silent stalkers and you have masterful hunters of the darkness. You will see owls in the day, but mostly when they are roosting. A few owls are diurnal, active in the day, too. These include the Burrowing Owl and the Short-eared Owl.
Owls do not construct nests, but rather look for a sheltered nesting site or an abandoned nest in trees, underground burrows, or in buildings, barns and caves. Barred and screech owls nest in holes abandoned by animals including squirrels and woodpeckers. Another advantage to breeding early for some species such as the Great Horned Owl is finding an ideal nesting spot. Unlike most owls, Great Horned Owls nest in the open. They will often take over a stick nest in the crook of a tree or take over the nest of a red-tailed hawk. In general, owls will generally try to reoccupy the same nesting territories in consecutive years. Screech owls roost in holes that face the sun so they can warm themselves while they sleep. The birds face outwards from the hole, their mottled feathers camouflaging them against the bark of the tree.
Because they feed on plentiful populations of small rodents throughout the winter, most owls found in Montana do not need to migrate like many bug- and seed-eating birds. They will also feed on insects, birds or other small mammals. Owls are efficient eaters and ingest all parts of their prey including skin, bone and feathers. After several hours they will regurgitate the indigestible bits in the form of a pellet, which are collected in their nest or roosting site. Finding pellets around the base of a tree or snag are a good indicator that there is an owl nest above your head.
Montana Fish, Wildlife and Parks Field Guide — http://fieldguide.mt.gov/
All About Birds, The Cornell Lab of Ornithology — http://www.allaboutbirds.org/