Timber Owl

 

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Timber Owl, Strix sylvestris L 40-50 cm, WS 100-110 cm, Family: Strigidae

 

IUCN Conservation Status: Near threatened (NT)

 

Description:    

Large owl with large round head and no ear tufts. Dark brown overall, with large black eyes and a distinctive facial disk marked with concentric striping. Back and wings heavily spotted with pale to cream, undersides lighter with dark striping and barring fading to pale undertail coverts. Bill and feet yellow.   

Voice:

Primary “song” is a distinct, six-syllable hoot pattern, often written as “Oh where do I come from?”. Song is low pitched, carries through forests quite far, and is fairly easy for humans to imitate. It is repeated often, given by both males and females. Female calls are slightly higher pitched. Pairs will engage in many varied vocalizations during courtship. Other calls include hisses, barks, bill snaps, and females will shriek when alarmed which sounds eerily similar to a woman screaming.

Habitat:          

Timber Owls are only found throughout Novasola’s western forests and less commonly in the east, more often in higher elevation conifer forests. They are most frequently seen in mature conifer forests, including coastal spruce and redwood and inland coopers-fir forests, but will also use mixed or deciduous forests and occasionally woodland and forest edge. They may also be found in wooded parks, yards, and other developed or urban green spaces so long as there is a mature canopy, though not as commonly as some other owl species.  

Discussion:      

Timber Owls are postcard members of typical nighttime Novasolan forests. Though not the most numerous owl, they are likely one of the two most observed, and thus well-known, owls endemic to the state, in part because of their obvious vocalizations. Their calls echo through the trees and are a staple sound of summer.

Timber Owls, as the name suggests, are found in forests. They prefer mature stands with tall canopies and an abundance of deadwood, but they are generalists and can thus be seen in most forest types on Novasola. They are fairly shy and typically avoid areas of dense human activity, though they will on occasion use developed areas, likely drawn there by the abundance of rodents. Though they can be found east of the Paramounts in low numbers, Timber Owls are far more numerous in the west and are heavily associated with western forests. They are cavity nesters, building their nests inside large tree cavities, which is why they need large, mature trees and snags.

Timber Owls are diet generalists, though they mainly eat small mammals, most often rodents like voles, mice, squirrels, chipmunks, and rats. They will also predate other mammals like shrews, rabbits, weasels, and skunks. A smaller portion of their diet, about ten percent, is composed of non-mammal vertebrates, mostly birds and terrestrial amphibians like frogs and newts. This is especially true west of the Paramounts where amphibians are more numerous. Timber Owls can take prey as large as themselves, including large hares and grouse, but prefer to catch small prey. In the east, where they overlap with Sloan’s Owls, they eat proportionally fewer birds and flying squirrels, which lowers competition with Sloan’s Owls which are better adapted to catching flying prey. Like other owls, Timber Owls have exceptional hearing which allows them to hear and locate prey even in total darkness, though their excellent night vision is nearly as impressive. Their hearing is so powerful that they can pinpoint prey like voles beneath snow. Also like other owls, Timber Owls have adaptations to their feathers which allows for completely silent flight, which helps them sneak up on prey from above.     

Generally solitary, Timber Owls are usually found alone or in pairs. They are monogamous and mate for life, and it may take multiple years to find a new mate after a previous one dies. They are territorial year-round and defend their territory from other Timber Owls, especially during the nesting season when they can become quite aggressive, even to other species. Territories are small, usually no larger than 10 square miles. Prior to the nesting season is when the owls are most active vocally, and their distinct “Oh where do I come from?” calls are given by both members of the pair, often as a duet, frequently, especially in the first few hours after sunset. Pairs build nests near the center of their territories in large tree cavities like hollowed snags, dead branches, and rotted holes. Timber Owls are especially common in redwood stands, as island redwoods are particularly susceptible to forming hollows. They have been shown to readily use nest boxes, which have been placed widely as a conservation strategy. Females will do all the incubation while males hunt and feed her and eventually the chicks, which usually number between three and five. Chicks will stay with the parents for a month or so after fledging but will soon move on to find territories of their own. Timber Owls are a long-lived species and can reach as old as 18 years in the wild. The oldest captive owl lived for 29 years.   

Members of the genus Strix, Timber Owls are related to mainland North America’s Barred, Spotted, and Great Gray Owls. Though generally more similar to the Barred Owl, Timber Owls are often closely associated with Northern Spotted Owls, in part due to their similar habitat requirements of large old-growth conifer forests, but also their relationship to the logging industry. Timber Owls were one of the wildlife species responsible for advocates changing logging regulations on the island in the 1990s. This was a Novasolan branch of a broader controversy termed the “Timber Wars” which revolved around the fight to halt logging in old-growth forests to protect the ecosystem generally and threatened species specifically, and on the mainland that meant the Northern Spotted Owl. On Novasola that mostly meant the Redwood Heron, though Timber Owls were included as sensitive species at the time and were often lumped with Spotted Owls.

 

Timber Owls can be difficult to observe, given their nocturnal nature and shy disposition. However, they are also extremely territorial and will respond to threats and intruders swiftly and aggressively. As such, a reliable way to see these owls is to mimic their hooting song, which is surprisingly easy for people. If done well, and near a Timber Owl territory, the owl will respond to the call and fly in close, even potentially acting aggressively to the caller. While people have been doing this for centuries, Richard Reichwald during the second NRC expedition became one of the first western scientists to employ the technique for study. Now, hooting playback surveys are a common practice among Timber Owl researchers and managers.  

 

“I have heard from the local population a trick which I am most eager to test. Supposedly the Indians here, and the whites soon after, have learned to call in the owls by mimicking their voices. The owls respond to the alien voices with anger and fury and soon appear from the darkness to combat the callers. The Indians do this to hunt the owls, from which they collect ceremonial feathers.” – Expedition logs, August 31, 1903

 

“Success! Marked success! Tonight, when the last light of the sun departed the western sky, I hurried into the woods to test my owl call. It has been a few weeks since I last heard a Timber Owl calling through the abyss, but I hoped to practice my calling so that I may be ready should I hear another. Given the late date, that Timber Owls are surely done with nesting by now, I expected nothing. However, after only a few attempts, I heard in the distance a response from an owl! After a few more calls and responses, I was met with more silence and assumed my encounter was over. I could not have been prepared, then, for what came next. As I turned back for camp a blood-curdling scream shot through the trees which was so loud, so piercing, and so pained that I must have jumped halfway to the moon. The owl I had called in did in fact come to investigate, silently, and there it sat on branch directly above me. It screamed again, a call to human for my comfort and one I have not yet heard, similar in quality to the screeches of the Barred Owls of New York. I had only a dim lantern with me and could thus not get a proper look at the bird but for the shine of its wide, round eyes. I shall take this experience with me to my last days, and I shall recommend this native trick for further use.” – Expedition logs, September 1, 1903   

 

“Best of luck to any who endeavor to see the Timber Owl with detail. Unwilling is the owl to be seen in daylight or away from the cover of trees. If even a man could find a Timber Owl in proper light, the bird’s plumage is cryptic such that it may never be discerned from the tree is clings to. Success is most likely in the spring when the birds are most active, in forest clearings where moonlight might piece the canopy.” – Manual to Novasolan Birds, 1914