Boreal Owls
Boreal Owls
Introduction: The Boreal, or Tengmalms Owl is a small owl with a large, rounded head and no ear-tufts. The species name funereus comes from the Latin word for funeral. In North America, where it is known as the Boreal Owl, it was named after the Greek god of the north wind, Boreas. In other parts of the world, it is known as Tengmalms Owl. Other names for this Owl are Richardsons Owl, Sparrow Owl, Partridge-haw and Pearl Owl.
[For help with terms used in the description, see parts of an owl. For general characteristics common to most owl species, see owl physiology.]
Description: Colouration varies widely between individuals, with some having reddish-brown hues, while others are more greyish.
The facial disc is whitish, surrounded by a dark rim with small white spots. There is a small dark portion between the eyes and the base of the bill. Eyes are pale to bright yellow. The cere and bill are yellowish horn.
Upper parts are dark brown with bold white spotting. Underparts are off-white, with broad streaks of darkish brown, denser on the breast and trailing off at the lower belly.
The tail is short and brown, with 4-5 white cross-bars. The legs and feet are covered with white feathers. Claws are darkish horn to blackish brown, and have very sharp blackish tips.
Size: Length 20-30cm. Wing length males 154-188mm, females 164-192mm. Tail length 75-114mm. Weight males 90-113g, females 126-194g.
Habits: A nocturnal Owl, also unsociable. Adult males are territorial, however, territories are small. Males will sing intensively only as long as they are unmated. Flight is straight and noiseless, with soft wingbeats.
Voice: The most common call is the territorial song of the male, which varies widely from individual to individual. It is a series of “Poop” notes followed by a 3-4 second break, then another series. The individual variation is in the number of notes and the pitch and speed at which the notes are uttered.
When the female approaches the singing male, the notes become more “stuttering”. This usually leads into a trill of up to 350 rapid notes, which is sung from potential nest sites to show the female.
The male will emit a low “Wood” or “Wood-whoohd” to contact a breeding female. To show aggression he can deliver a whip-like “zjuck” sound.
The females call is infrequently heard, and similar to the males, but fainter, higher pitched and not as clear. An aggressive female may utter a sharp “Jack” as well as hoarse “oohwack” and croaking sounds “kraihk, kwahk”.
When the male announces his arrival with trills or “wood” calls, the female will respond from the nest hole with a high pitched “seeh”, sometimes with a verse of suppressed song. Her contact call is a mewing, hoarse “zuihd”.
Hunting & Food: Boreal Owls usually hunt by perching on low branches or tree trunks. The Owl will scan the ground by moving its head slowly from side to side, listening for movement of potential prey, as they hunt primarily using their excellent, directional hearing. When a victim is located, the Owl will swoop on it from the perch.
Prey Items are mainly small rodents, especially Voles. They also eat lemmings, shrews, mice, and moles. They occasionally take small birds, squirrels, bats, frogs and beetles.
Pellets are thick, grey and about 22x12mm and found mostly around the daytime roost.
Breeding: The Boreal or Tengmalms Owl nests mainly in old woodpecker cavities, but may also use natural cavities. They will take readily to artificial nest boxes.
Males