This call is given in social interaction or when the owl tries to scare away other animals. Namely, the scops owls give a whistling call or a row of high-pitched hoots with fewer than four individual hoots per second. While late-19th-century ornithologists knew little of the variation of these birds, which often live in far-off places, with every new taxon described a few differences between the Old and New World "scops" owls became more and more prominent. The splitting of Otus sensu lato Pacific screech owl ( Megascops cooperi) The screech owls also have a different placement of the procoracoid (less of an anterior incline) and coracoid bones compared to other New World owls. However that may be, the hypothesis that the group evolved from Old World stock is tentatively supported by cytochrome b sequence data. Like almost all scops and screech owls today, their common ancestor was in all probability already a small owl, with ear tufts and at least the upper tarsus ("leg") feathered. Note, no reliable estimate of divergence time is known, as Otus and Megascops are osteologically very similar, as is to be expected from a group that has apparently conserved its ecomorphology since before its evolutionary radiation. The scops and screech owl lineage probably evolved at some time during the Miocene (like most other genera of typical owls), and the three (see below) modern lineages separated perhaps roughly 5 million years ago. A screech owl fossil from the Late Pliocene of Kansas (which is almost identical to eastern and western screech owls) indicates a longstanding presence of these birds in the Americas, while coeval scops owl fossils very similar to the Eurasian scops owl have been found at S'Onix on Majorca. What is certain is that they are very closely related they may be considered sister lineages which fill essentially the same ecological niche in their allopatric ranges. The evolutionary relationships of the scops and screech owls are not entirely clear. The type species is the eastern screech owl ( Megascops asio). The genus Megascops was introduced by German naturalist Johann Jakob Kaup in 1848. The distinctness of many species of screech owls was first realized when vastly differing calls of externally similar birds from adjacent regions were noted.Įvolution, taxonomy, and systematics Calls differ widely between species in type and pitch, and in the field are often the first indication of these birds' presence, as well as the most reliable means to distinguish between species. They also have a kind of " song" used in courtship, and as a duet, between members of a pair. Their normal territorial call is not a hoot as with some owls, but a trill consisting of more than four individual calls per second given in rapid succession (although the sound does not resemble screeching or screaming). The screech owls are named for their piercing calls. Northern screech owls are found in eastern states, such as New Jersey and New York. The young of most screech owls are altricial to semialtricial. These birds are monogamous, with biparental care. During the incubation period, the male feeds the female. The females select their mate based on the quality of the cavity and the food located inside. During the late winter breeding season, however, males make nests in cavities, sometimes reusing abandoned nests of other animals, to try to attract females. They usually carry their prey back to their nests, presumably to guard against the chance of losing their meal to a larger raptor. They also possess well-developed raptorial claws and a curved bill, both of which are used for tearing their prey into pieces small enough to swallow easily. Screech owls have a good sense of hearing, which helps them locate their prey in any habitat. They prefer areas that contain old trees with hollows these are home to their prey, which includes insects, reptiles, small mammals such as bats and mice, and small birds. Screech owls hunt from perches in semiopen landscapes. This coloration helps them get camouflage against the tree bark. They have different brownish hues with whitish, patterned underside. They have prominent, wide-set feather tufts with bright yellow/green eyes. They are small and agile, and about 7 to 10 inches tall and have a wingspan around 18 to 24 inches. Similar to other owls, the screech owl females are larger than the males of their species. Long-tufted screech owl ( Megascops sanctaecatarinae) Description Some species formerly placed with them are nowadays considered more distinct (see below for details). Screech owls are restricted to the Americas. For most of the 20th century, this genus was merged with the Old World scops owls in Otus, but nowadays it is again considered separately based on a range of behavioral, biogeographical, morphological, and DNA sequence data. Screech owls are typical owls ( Strigidae) belonging to the genus Megascops with 23 living species.
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