Appearance

Megascops are small owls with large heads and relatively short tails; many species also have a tuft of feathers ("ear" tufts) on either side of the head. Koepcke's Screech-Owl is a medium to large sized screech-owl. The plumage generally is typical for the genus, but with a relatively coarse plumage pattern. The base color of the upperparts is brown (northern populations) or gray (in the southern subspecies, hockingi). The facial disk is paler, whitish gray, with a prominent blackish rim, and is bordered above by whitish "eyebrows". The feathers over the eyes are only somewhat elongated, producing only a short pair of "ear" tufts. The feathers of the upperparts have broad blackish shaft streaks, with dusky transverse barring. The outer webs of the scapulars are white, forming a line of whitish spots along the edge of the mantle. The underparts are grayish white, with broad blackish brown shaft streaks and narrower transverse barring. The irides are pale yellow, as in many other species of Megascops.

Koepcke's Screech-Owl is very similar to Peruvian Screech-Owl (Megascops roboratus), and in northern Peru these two species are generally sympatric. It is rare for Koepcke's and Peruvian to be syntopic, however, as Koepcke's occurs at higher elevations (2200-4000 m) than does Peruvian (which primarily is below 900 m, although in Ancash it may occur up to 2100 m). Peruvian Screech-Owl also is smaller than Koepcke's (especially in the case of subspecies pacificus, along the west slope of the Andes), its crown tends to be darker than the back (not concolor, as in Koepcke's), and Peruvian has a narrow whitish band across the nape (lacking in Koepcke's). These two species also have very different vocalizations: the stuttering, staccato song of Koepcke's is nothing like from the purring, trilled song of Peruvian.

Koepcke's Screech-Owl also is similar to Tropical Screech-Owl (Megascops choliba). Tropical is exclusively a lowland species, and so it and Koepcke's do not overlap geographically. The rolling trilled song of Tropical, ending with an emphatic punch, also is very different from the song of Koepcke's.

The following description is based on König and Weick (2008) and Fjeldså et al. (2012), and refers to nominate koepckeae; see also Geographic Variation:

Adult: Sexes similar. Facial disk whitish gray, speckled or mottled darker, and becoming paler towards the outer rim; prominent blackish rim to facial disk. Short streak above eyes ("eyebrows") whitish, mottled darker. Crown blackish brown with fine pale brown speckling, becoming ochre whitish towards the forecrown. No pale collar on hindcrown or nape. Upperparts rather dark brown or grayish brown, with relatively broad blackish or dusky shaft streaks and dark transverse barring, with ochre to whitish spots. but with little tendency to vermiculations. Outer webs of scapulars whitish, edged with blackish, forming a line of whitish spots over each wing. Rectrices dark brown with narrow ochre bars and small speckles. Remiges indistinctly barred dark and pale, primaries with uniform dark tips. Underparts grayish white with broad blackish brown shaft streaks and a few irregular bars. Sides of neck and of upper breast washed with pale brownish ochre. Tarsi feathered to base of toes, ochre with with brown speckles.

Nestling: Covered in pale gray down (Fjeldså et al. 2012).

Undescribed; probably follows the complex basic molt strategy.

Iris: yellow, deep yellow

Bill: bluish to greenish horn with paler tip, grayish green; cere greenish

Toes: grayish brown, greenish gray, pale tan, and perhaps pink

Bare parts color data from König and Weick (2008) and Fjeldså et al. (2012).

Total length: 24 cm (König and Weick 2008)

Linear measurements (from Fjeldså et al. 2012; sexes presumably combined):

koepckeae (n = 6)

wing length (flattened): mean 177.2 ±4.29 mm (range 173-185 mm)

tail length: mean 99.3 ± 1.71 mm (range 98-102 mm)

bill length (to base): mean 21.7 ± 0.73 mm (range 20.8-22.3 mm)

tarsus length: mean 28.7 ± 0.70 mm (28-30 mm)

hockingi (n = 8)

wing length (flattened): mean 172.3 ±2.45 mm (range 169-174 mm)

tail length: mean 94.6 ± 5.16 mm (range 86-103 mm)

bill length (to base): mean 21.5 ± 1.73 mm (range 19.0-23.7 mm)

tarsus length: mean 30.7 ± 2.63 mm (25.3-37.0? mm)

Mass (from Fjeldså et al. 2012; sexes presumably combined):

koepckeae (n = 6): mean 119.9 ± 4.8 g (range 112-127 g)

hockingi (n = 3): mean 124.3 g (range 121-130 g)