Hawks Aloft, Inc.
Conservation, Avian Research, and Education
PO Box 10028 - Albuquerque, NM 87184 - (505) 828-9455

 

Northern Saw-whet Owl (Aegolius acadicus)

 Field Marks:

-  length: 7-8 in. wingspan: 15 in.

-  rounded wings, and short tail seen only during flight

-  white circles around each eye and a white “Y” between eyes and beak

            -  lacks ear tufts 

Breeding Range:

Northern Saw-whet Owls breed in wooded areas in North America, and high elevation mountains in southern United States, Mexico and Central America.   

Wintering Range:

Individuals in the northernmost one-third of the breeding range migrate during the winter, while birds in the middle and southern breeding range do not.  Birds breeding along the Pacific Coast may move inland during the winter.   

Habitat Preferences:

Northern Saw-whet Owls prefer forested areas of all types, although population densities are highest in coniferous forests.  During the non-breeding season, they use more open areas of the forest. 

Nesting:

Northern Saw-whet Owls nest in natural or man-made cavities with openings 2-3 inches in diameter.  The clutch size averages 5-6 eggs.  Young hatch after 27-29 days, and fledge 28 days later.  Young are cared for by the female for the first 18 days after hatching, then by the male until the young are independent.  Some female Saw-whet Owls leave the first clutch in the care of the male, then find a new male and lay a second clutch.  This species is moderately sensitive to nest disruption, and they may abandon eggs or young early in the nesting season.   

Feeding:

Northern Saw-whet Owls are exclusively nocturnal, and they begin hunting within one-half hour of sunset.  They forage along the borders of open woodlands, feeding primarily on small mammals, particularly wood and deer mice.  Occasionally, bird bones or insect skeletons are found in their pellets.    

Conservation Status:

Because of their reclusive nature, only rough population estimates exist.  A conservative estimate of the total population is between 100,000 and 300,000 individuals.  Northern Saw-whet Owls are not currently listed as endangered or threatened in any state.  The most common documented cause of death for adults is vehicle collisions.  Habitat availability is a population-limiting factor in much of the United States.  The introduction of artificial nest boxes might minimize the impact of habitat loss.  A measurable number of young are lost to the illegal pet trade.