Above: Northern Saw-whet Owl in southwest Winnipeg, MB, February 21, 2022. Photo by Katharine Schulz.
The Northern Saw-whet Owl (Aegolius acadicus) is Manitoba’s smallest owl, and indeed the smallest in Eastern North America, with males weighing about 75 grams or about as much as an American Robin, and females, only about 25% more. The genus Aegolius is derived from an Ancient Greek word meaning “a bird of ill omen” and the specific epithet acadicus refers to the European colony of Acadia (now mostly Nova Scotia) where it was first observed. The common name is generally attributed to the similarity of one of its calls to the sound of handsaw teeth being sharpened i.e. whetted with a whetstone (although there seems to be little consensus as to exactly which is the call in question!)
Of the 11 regularly occurring owl species of the family Strigidae in Manitoba, the Northern Saw-whet Owl is one of, if not the most frequently detected species on the long-running, volunteer-based Manitoba Nocturnal Owl Survey, along with the Great Horned Owl (Bubo virginianus), and followed by the closely related Boreal Owl (Aegolius funereus). Despite the population levels suggested by this and other surveys in Manitoba, where it is considered a fairly common breeder in the southern half of the province, the Northern Saw-whet Owl is far more easily heard than seen due to its nocturnal and secretive habits.
Above: Northern Saw-whet Owl being investigated by a Black-billed Magpie in southwest Winnipeg on February 21, 2022. Note the relatively diminutive size of the owl. Photos by Katharine Schulz.
How do I recognize it?
This diminutive owl is rather large-headed and short-tailed, with a rotund body, similar in shape to its slightly larger relative, the Boreal Owl. The Northern Saw-whet’s rounded head lacks feather “ear” tufts and the adult’s facial discs are warm brown, with a whitish zone around the yellow-golden eyes, forming radial white streaks towards the edge of the disc. A white “Y” extends from above the bill to above each eye, and this feature appears particularly pronounced in contrast to the dark chocolate brown facial disc of juvenile and immature birds. The mantle and upper parts of the adult are rusty brown with white spots and the flight feathers of the rounded wings are also spotted white, while the lower parts are whitish with broad reddish-buff streaks. Juveniles have an unmarked cinnamon-buff belly and an unspotted dark brown back.
Above: An immature Northern Saw-whet Owl surveying its wooded habitat. Photo by Christian Artuso
In contrast to the Boreal, the bill and cere of the Northern Saw-whet Owl are blackish versus pale, and its facial disc does not have the bold black border of the Boreal, but rather is narrowly edged with light and dark spots. The head and particularly forehead, is covered with fine white streaks, while tiny white spots cover the crown of the adult Boreal.
Above: Northern Saw-whet Owl in southwest Winnipeg on February 21, 2022. Note the fine white streaking on the forehead, the black bill and the lack of a black border to the facial disc which helps differentiate it from a Boreal Owl. Note also relatively relaxed facial disc in comparison to the photos below. The close-up of the face shows the soft finer feathers of the facial disc which allow sound to easily pass through to the ears. Photo by Katharine Schulz
As with other owls, it has a highly developed auditory system and it is one of several owls that have ears located asymmetrically, with one ear opening higher than the other. This unique adaptation allows determination of the height and direction of sound as the owl pinpoints the source. The concave facial disc functions as a parabolic sound collector and the facial ruff (outer ring of stiff feathers) forms a curved wall around the owl’s face to reflect sound and increase the surface area over which sound is collected. An owl can alter the shape of its facial disc using special muscles to channel sounds at will.
Above: Northern Saw-whet Owl with facial disc optimized as it listens intently. Note the erect outer ring (facial ruff) of stiffer feathers in the close-up of the face. Photo by Christian Artuso.
Above: Northern Saw-whet Owl fixed on potential prey (a Redpoll) in southwest Winnipeg on February 21, 2022. Note again the facial ruff. Photo by Katharine Schulz.
Does it migrate?
Historically, migration was poorly understood, and until the early 1900’s, it was generally assumed that the Northern Saw-whet Owl was a rare resident throughout its range, not a migrant. Eventually, sufficient observations and research led to the realization that the species was far more numerous than initially believed, and coupled with banding operations, it became better understood that the Northern Saw-whet Owl does indeed migrate, with large numbers observed congregating during spring and fall migrations on the shores of large waterbodies.
However, they don’t necessarily have consistent migration routes and there is some banding evidence suggesting that male saw-whets may be less migratory than females, even in the northern parts of its range. According to Duncan, migration appears to be female and juvenile-biased, while territorial males may be more reluctant to leave suitable nesting sites. They also exhibit somewhat nomadic behaviors such as breeding in different places and moving in response to food resources. Migration occurs throughout the night, with peak movements on clear nights.
While some do remain behind in Manitoba during the winter months, attempted wintering here can be fatal, and many perish when food is scarce or a thick, icy crust on the snow impedes hunting. The majority of Northern Saw-whet Owls depart the Prairie Provinces from mid-September to late October and appear to follow an east-southeasterly trajectory, based on information derived from banding recaptures. For example, according to the Manitoba Breeding Bird Atlas, birds banded at Delta Marsh Bird Observatory have been recaptured at four locations in Wisconsin and one in western Quebec. Banded owls have been recaptured over 600 miles away during migration.
Where does it live?
The Northern Saw-whet Owl is a North American species, breeding from southwest Mexico, north to the western and northeastern United States, and across southern Canada to southern coastal Alaska. As noted in the Manitoba Breeding Bird Atlas, it is most common here in the Boreal Hardwood Transition region, with possibly the greatest probability east and southeast of the south basin of Lake Winnipeg. Outside the southern boreal forest, it may occur in outlying pockets such as Birds Hill and Turtle Mountain Provincial Parks, the Spruce Woods and Lauder Sandhills regions, and within other wooded areas of the southern Prairie Pothole region.
It inhabits a variety of woodland habitats, including mixed coniferous and deciduous forests and riparian woodlands, although population densities seem to be highest in coniferous forests. Mature or old growth forests are preferred and frequently used for their cavity-nesting opportunities, and the territory size can range up to 950 acres. The larger proportion of deer mice in the diet as opposed to the voles prioritized by the Boreal Owl, may have an effect on the Northern Saw-whet’s habitat preferences and distribution.
The Northern Saw-whet Owl hunts mainly at dusk and dawn, usually from low perches (about 1.5 to 3 m) and most often using the “sit and wait” tactic to drop down to prey on the ground. Only half of any prey item is usually eaten at once, starting with the head, and uneaten food may be cached on branches. It feeds almost entirely on small mammals, primarily the aforementioned deer mice, but will also take shrews, voles, moles, bats, and flying squirrels, as well as small birds, and occasionally even larger birds such as Rock Pigeons, as it is capable of killing prey up to four times its weight. It may also take frogs, insects and spiders. In turn, Northern Saw-whet Owls may be preyed upon by larger raptors, including larger owls such as Great Horned Owls, Barred Owls and Long-eared Owls.
Above: Northern Saw-whet Owl with small mammal prey. Photo by Christian Artuso.
The Northern Saw-whet Owl is considered mostly monogamous during a season, but years of prey abundance may rarely result in additional pairing. Each year they will pair up with a new mate. After courtship, it is believed females chose the nest site. They often chose a hole previously excavated by Northern Flickers or Pileated Woodpeckers in dead snags, but they may also use natural cavities, and take readily to nest boxes. They lay 4-7 (usually 5-6) smooth white eggs at 2 day intervals, on debris at the bottom of the cavity, approximately 1 to 13 m off the ground. The male provides her with food while she incubates 26 to 29 days and also while she broods the hatched chicks until they can control their own body heat at about 18 days old. She keeps the nest very clean until then, but a mess starts to accumulate once she leaves. The young leave the nest after approximately 30 days and the male continues to provide them with food for another 30 days.
Where can I see it?
As it is secretive and very good at remaining silently incognito in its daytime roosts, this infrequently seen nocturnal owl is best detected by its incessant “tooting” vocalization during spring migration and the early part of the breeding season. Northern Saw-whet Owls often start calling during warmer periods in March in Manitoba, although the peak calling period is in April to early May. The primary courtship call is a rhythmic series of whistled “toot” notes (somewhat resembling the warning beeps of a truck backing up, but a bit faster, at a rate of about 1.5 per second), which may last for extended periods without a break and can be heard up to a half mile away. Study recordings to learn how to recognize the sound, but please do not use audio playback in an attempt to draw out any owl (outside of a scientific research protocol.) Better yet, consider volunteering with the Manitoba Nocturnal Owl Survey to help further our knowledge of these and other owls in our province. https://naturecounts.ca/nc/mbowls/main.jsp
Above: A Northern Saw-whet Owl in a typical daytime roost, concealed in the protection of a cedar tree in St. Andrews, MB. Photo by Garry Budyk.
During the early breeding season, areas for potential listening could include wooded river valleys, and other woodland habitats with dense vegetation as described earlier. Some areas that have had proven successful in the past include along Spruce Siding Road east of Winnipeg, Birds Hill Provincial Park, Sandilands and Agassiz Provincial Forests and Nopoming and Whiteshell Provincial Parks. In southwestern Manitoba, mature poplar stands in the Lauder Sandhills are worth checking, as is the vicinity of Hwy 10 through Riding Mountain National Park etc.
As indicated earlier, although the majority migrate, a few individuals, often territorial males, may remain and attempt to overwinter, sometimes appearing in cold winter months in woodlots, city parks or farmyards. (Others may also appear in such areas during migration.) They may also appear in suburban gardens, to try their luck at potential prey attracted to bird feeders, thus allowing unexpectedly open daytime views, with deciduous trees and shrubs devoid of leaves. The photos within this article labelled as taken February 21, 2022 in southwest Winnipeg was one such occasion. (PLEASE NOTE that these particular photos were all taken with a zoom lens through the window of the house only, as a nocturnal owl in this situation of cold, deep snow and attempted daytime hunting is likely already under considerable stress and should never be approached under any circumstances. Its life depends on the energy and focus to hunt successfully.)
Above: Northern Saw-whet Owl taking a break from daytime hunting attempts under harsh winter conditions in southwest Winnipeg on February 21, 2022. (In the second photo, it appears to be yawning as it was not observed to expel a pellet.) Photos by Katharine Schulz.
Conservation Status.
Two subspecies of Northern Saw-whet Owl are generally recognized, with the familiar migratory Aegolius acadicus acadicus occurring over the entire range, whereas the non-migratory Aegolius acadicus brooksi is endemic to Haida Gwaii (formerly Queen Charlotte Islands) where it is resident in old growth forests in this archipelago off the northern Pacific coast of British Columbia. This subspecies differs genetically, somewhat morphologically (similar appearance but smaller and darker with a longer tail) and behaviourally from continental populations and is threatened by on-going logging of its preferred old forest nesting habitat, nest predation by introduced species, and by over-browsing by introduced deer, impacting prey availability.
Christmas Bird Count and Nocturnal Owl Surveys across Canada have suggested an ongoing increase since 1970 of the acadicus subspecies, although confidence in this trend is considered low. According to the Manitoba Breeding Bird Atlas, abundance is difficult to ascertain as the population varies from year to year, possibly fluctuating with prey density; however, in peak years (at 3 to 6 year intervals) it has been the most commonly recorded owl in the province.
Globally, the IUCN (International Union for Conservation of Nature) status of the Northern Saw-whet Owl is Least Concern. Within Canada, the brooksi subspecies was assessed as Threatened under COSEWIC (Committee on the Status of Endangered Wildlife in Canada) in 2006 and again in 2017, and it has been listed as Threatened under the federal Species at Risk Act since 2007.
As with many species, one of the greatest threats to the Northern Saw-whet Owl throughout its range is destruction of habitat, particularly of their favored mature forest stands, with the corresponding loss of nesting snags and prey availability due to pressure from logging, human encroachment for development and forest fires.
Did you know?
According to the Cornell Laboratory of Ornithology, migrating Northern Saw-whet Owls can cross the Great Lakes or other large bodies of water. One was recorded 70 miles from shore in the Atlantic Ocean when it landed on a fishing vessel in October of 1999.
In terms of lifespan, one captive bird held by a rehabilitation facility was known to live for 16 years, while the oldest wild Northern Saw-whet Owl previously on record was at least 9 years and 5 months of age. It was originally banded in Ontario in 1999 and was recaptured and released by a bander in Minnesota in 2007. However, more recently, a wild female Northern Saw-whet Owl caught in Pennsylvania in 2022 as part of Project Owlnet, had been banded as a two-year old in Ohio in 2009, making it almost 14.5 years old! (Project Owlnet, initiated in the mid-1990’s, is a collaborative network of over 300 researchers from over 100 banding stations in Canada and the U.S. that are attempting to understand the movement ecology and population dynamics of migratory owls, primarily Northern Saw-whet Owls, while also beginning to explore the movements of other species, including Boreal and Long-eared owls. https://www.projectowlnet.org/)
Above: Another lovely Northern Saw-whet Owl resting in the comfort of a cedar tree. Photo by Christian Artuso.
Written by Katharine Schulz, March 3, 2026
References
Cornell Lab of Ornithology. 2025. All About Birds. Cornell Lab of Ornithology, Ithaca, New York. https://www.allaboutbirds.org Accessed January 24, 2026
Duncan, J. 2013. The Complete Book of North American Owls. Thunder Bay Press, San Diego, CA, USA.
Environment and Climate Change Canada and Birds Canada. 2024. The State of Canada’s Birds – Northern Saw-whet Owl. Data accessed from NatureCounts, Birds Canada. https://doi.org/10.71842/t7z2-sk88 Accessed February 8, 2026
Holland, G.E., C. E. Curtis and P. Taylor. in The Birds of Manitoba Ed. Peter Taylor, 2003. Manitoba Avian Research Committee, Manitoba Naturalists Society, Winnipeg, Manitoba.
Lewis, Deane. 2020. The Owl Pages. https://www.owlpages.com/owls/species.php?s=3030 Accessed February 23, 2026.
Koes, R. F. 2019. Northern Saw-whet Owl in Artuso, C., A. R. Couturier, K. D. De Smet, R. F. Koes, D. Lepage, J. McCracken, R. D. Mooi, and P. Taylor (eds.). The Atlas of the Breeding Birds of Manitoba, 2010-2014. Bird Studies Canada. Winnipeg, Manitoba http://www.birdatlas.mb.ca/accounts/speciesaccount.jsp?sp=NSWO&lang=en [08 Feb 2026]
Rasmussen, J. L., S. G. Sealy, and R. J. Cannings. 2020. Northern Saw-whet Owl (Aegolius acadicus), version 1.0. In Birds of the World (A. F. Poole, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://birdsoftheworld.org/bow/species/nswowl/cur/introduction Accessed February 8, 2026.
Sibley, D. A. 2014. The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.
The Owl Foundation. 2008. The Northern Saw-whet Owl. Vineland Station, Ontario http://www.theowlfoundation.ca/ Accessed February 8, 2026.
Weidensaul, S. 2024. “Three Decades of Wee Owls” in BWD (formerly Bird Watcher’s Digest) November/December 2024, pp. 9-14.