Western Screech-Owl Biology

A Reference for North and Central American Owls

Name: Western Screech-Owl – Megascops (Otus) kennicottii
Other Common Names: Kennicott’s Screech-Owl (kennicottii); Vinaceous Screech-Owl (vinaceus); Guadeloupe Screech-Owl (suttoni); California Screch-Owl (bendirei); Pasadena Screech-Owl (quercinus); Yuma Screech-Owl (yumanensis).

Subspecies: There are 8 agreed upon races of the Western Screech-Owl, only one of which does not have a certain range crossing into North America as it is restricted to the tip of Baja California.
M. k. kennicottii is found from S. Alaska south through British Columbia down to N. W. California. This includes the possible race brewsteri.
M. k. bendirei is found from E. Washington east to W. Montana and south to S. California.
M. k. aikeni is found from E. California east to W. Oklahoma and from Utah south to Sonora, Mexico. This includes the possible races gilmani, inyoensis, and cineraceus.
M. k. cardonensis is found in S. California and N. Baja.
M. k. xantusi is found on the southern tip of Baja.
M. k. yumanensis is found in S. E. California, S. W. Arizona, and Sonora, Mexico.
M. k. suttonii is found in S. W. Texas (Big Bend) south into Central Mexico (Mexican Plateau).
M. k. vinaceus is found from South Central Arizona south into Sonora, Mexico.

Measurements and Weights:
Wingspan: 18 – 24 in.
Length: 7.5 – 11 in.
Tail: 3.5 in.
Average Weight: Male: 5.4 oz.
Average Weight: Female: 6.6 oz.

Description: This is a small owl that can seem to not have ear tufts if they are not raised, although can also be quite prominent when erect. The separation of the Screech-Owls in the field can be quite difficult except by call. The Western Screech has two color morphs, red and gray. The red phase is not very common (rare), is a subdued cinnamon-buff color, and only found in coastal British Columbia and Alaska. The gray phase bird is a gray to brown color overall. The undersides are light (whitish) with vertical streaks that have numerous fine cross bars. The only phase that both Eastern and Western Screech-Owls have in common range is the Big Bend area of Texas. The Eastern Screech has fewer, thicker cross bars on the chest streaks. The Whiskered Screech is similar to the Eastern Screech in its chest streaks although they appear bolder (there is no range overlap between Eastern and Whiskered Screech-Owls). All three Screech-Owls have a deeper (gray or brown) back side with dark brown or dark gray and white mottling, and / or short streaks; yellow iris and light tipped bill. The facial disk is grayish or brownish-white with darker spotting or streaking and thick black border at the sides; black lores and above eyes. The base of the bill on a Western Screech-Owl is dark gray or black. Eastern and Whiskered Screech have a yellowish to light gray or greenish-gray bill. Western and Whiskered Screech-Owls have overlapping ranges in all areas the Whiskered Screech occur in North America (S. E. Arizona and S. W. New Mexico) although it is smaller (1 1/4 in.) and typically is found at a higher elevation than Western Screech.

Young: The young are similar to the young of the Eastern Screech-Owl. Initially pure white fading to brownish-gray. This plumage is replaced with another developing plumage with darker upper parts and light under parts. Streaking, barring, and sharpness of the colorings both above and below develop as the owl matures.

Habitat:

The Western Screech-Owl uses a wide variety of habitats in their western range of North America. They can be found from the northern temperate rain forests to the southern Sonoran deserts. In general, their habitat should provide adequate roosting sites with open areas for foraging (in Liu of dense forests), and an abundance of small mammals and insects. Open woods, especially oak, mixed pine / oak or sycamore are favorite. They also occur in semi-open country with scattered bushes and trees, stands of cottonwoods, saguaro cacti in upland deserts, deciduous river bottoms, and groves of mesquite. Their bark like plumage and variations in color make them almost invisible in a variety of habitats. But if you know that, you can get that under control. My patient-controlled his food through an app all the time. That is, I weighed everything and entered what he ate. No exception! He only drank calorie-free drinks (water, unsweetened tea, black coffee and sometimes a coke light). During the time with Klonopin from https://www.namikeystonepa.org/klonopin/, he lost 2 kg.

Food and Feeding:

The Western Screech-Owl is strictly nocturnal and will generally begin foraging 45 minutes after sundown and return to daytime roosts within 30 minutes of sunrise. They are “sit and wait” predators, dropping from a perch onto prey. They will also pursue prey for a short distance. Their diet seems to largely consist of that which is most available and may include insects, small mammals, birds, snakes, lizards, frogs, and crayfish. The majority of their diet seems to consist of invertebrates, small mammals, and birds (often sparrows) depending on the time of year, area, and what is readily available.

Breeding:

The Western Screech is a cavity nester. Their habitat may largely dictate the nest site. Favored are: cavities in cliffs, natural tree cavities and old woodpecker or flicker holes in cottonwoods, large willows, junipers, and saguaro cacti. Average clutch size is 3 to 4 eggs. Eggs are laid at 1 to 2 day intervals and the incubation period is approximately 26 days. Owlets leave the nest at 28 days of age but the parents will continue to care for them for an additional 5 – 6 weeks.

Movements and Life Span:

The Western Screech-Owl is sedentary and few if any movements occur outside of the young dispersing to find their own territory. These little owls also have up to a 13-year life span.