Screech owl

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Screech owl
Temporal range: Miocene to present
morph
Gray morph
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Strigiformes
Family: Strigidae
Genus: Megascops
Kaup, 1848
Type species
Strix acio
Linnaeus, 1758
Species

Some 22, see text

Synonyms

Macabra Carlo Bonaparte, 1854

Screech owls are

DNA sequence
data.

Screech owls are restricted to the Americas. Some species formerly placed with them are nowadays considered more distinct (see below for details).

Long-tufted screech owl (Megascops sanctaecatarinae)

Description

Similar to other owls, the screech owl females are larger than the males of their species. They have a compact size and shape. They are small and agile, and about 7 to 10 inches tall and have a wingspan around 18 to 24 inches. They have prominent, wide-set feather tufts with bright yellow/green eyes. They have different brownish hues with whitish, patterned underside. This coloration helps them get camouflage against the tree bark.

Ecology and behavior

Screech owls hunt from perches in semiopen landscapes. They prefer areas that contain old trees with hollows; these are home to their prey, which includes

mammals
such as bats and mice, and small birds. Screech owls have a good sense of hearing, which helps them locate their prey in any habitat. 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. They usually carry their prey back to their nests, presumably to guard against the chance of losing their meal to a larger raptor.

Screech owls are primarily solitary. During the late winter breeding season, however, males make nests in cavities, sometimes reusing abandoned nests of other animals, to try to attract females. The females select their mate based on the quality of the cavity and the food located inside. During the incubation period, the male feeds the female. These birds are

altricial to semialtricial.[1]

Northern screech owls are found in eastern states, such as

song
" used in courtship, and as a duet, between members of a pair. 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. The distinctness of many species of screech owls was first realized when vastly differing calls of externally similar birds from adjacent regions were noted.

Evolution, taxonomy, and systematics

The genus Megascops was introduced by German naturalist

osteologically very similar, as is to be expected from a group that has apparently conserved its ecomorphology since before its evolutionary radiation. 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.

However that may be, the hypothesis that the group evolved from Old World stock

anterior incline) and coracoid bones compared to other New World owls.[9]

The splitting of Otus sensu lato

Pacific screech owl (Megascops cooperi)

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. Namely, the scops owls give a whistling call or a row of high-pitched hoots with fewer than four individual hoots per second. This call is given in social interaction or when the owl tries to scare away other animals. The screech owls, though, are named for their piercing trills of more than four individual notes per second, and as noted above, they also have a kind of song, which is absent in the scops owls. A few other differences are seen, such as brown coloration below being common in scops owls and almost never seen in screech owls, but the difference in vocalizations is most striking.

By the mid-19th century, Otus was becoming identified as encompassing more than one genus. First, in 1848, the screech owls were split off as Megascops. Subsequently, the highly

monotypic genus Macabra in 1854. Gymnasio was established in the same year for the Puerto Rican owl, and the bare-legged owl
(or "Cuban screech owl") was separated in Gymnoglaux the following year; the latter genus was sometimes merged with Gymnasio by later authors.

Bare-shanked screech owl (Megascops clarkii)

By the early 20th century, the

mtDNA cytochrome b across a wide range of owls found that even the treatment as subgenera was probably unsustainable and suggested that most of the genera proposed around 1850 should be accepted.[7][8] Though some debate arose about the reliability of these findings at first,[11] they have been confirmed by subsequent studies. In 2003, the AOU formally accepted the genus Megascops again.[12]

The bare-legged owl was also confirmed as distinct enough to warrant separation in its own genus. Furthermore, the white-throated screech owl was recognized as part of an ancient lineage of Megascops – including also the whiskered screech owl and the tropical screech owl, which previously were considered to be of unclear relationships – and indeed its call structure is not too dissimilar from the latter. Its distinct coloration, approximated in the southern whiskered screech owl (Megascops trichopsis mesamericanus), is thus likely the result of strong genetic drift.

Additionally, a population of the tropical screech owl from northern Colombia has recently been proposed as the Santa Marta screech owl (Megascops gilesi) to the

Species

Western screech owl (Megascops kennicottii)
morph individuals of the tropical screech owl
(Megascops choliba)

The genus contains 22 species:[15]

References

  1. /
  2. ^ Kaup, Johann Jakob (1848). "Uebersicht der Eulen (Strigidae)". Isis von Oken (in German). Cols. 753–774 [765,769].
  3. .
  4. UMMP 50982, a partial left coracoid
    from Fox Canyon: Ford (1966).
  5. ^ Mlíkovský, Jirí (2002). Cenozoic Birds of the World, Part 1: Europe Archived 2011-05-20 at the Wayback Machine. Ninox Press, Prague.
  6. ^ Johnson, David (2003). Owls in the Fossil Record. The owl pages.
  7. ^
    S2CID 28746107
    .
  8. ^
  9. .
  10. ^ Marshall, Joe T. & King, Ben (1988). Genus Otus. In: Amadon, Dean & Bull, J: Hawks and owls of the world: A distributional and taxonomic list. Proceedings of the Western Foundation of Vertebrate Zoology 3: 296–357
  11. ^ "Proposal (#58): Elevate subgenus Megascops (New World Otus) to full generic status". South American Classification Committee. 2003. Retrieved 27 December 2017.
  12. .
  13. ^ Krabbe, Niels K. (2017). "A new species of Megascops (Strigidae) from the Sierra Nevada de Santa Marta, Colombia, with notes on voices of New World screech-owls" (PDF). Ornitología Colombiana. 16: eA08.
  14. ^ "Proposed Splits/Lumps « IOC World Bird List". www.worldbirdnames.org. Retrieved 2018-01-28.
  15. ^ Gill, Frank; Donsker, David; Rasmussen, Pamela, eds. (December 2023). "Owls". IOC World Bird List Version 14.1. International Ornithologists' Union. Retrieved 8 March 2024.

Further reading