IDENTIFICATION A medium-sized owl (29–38cm), generally disc. Upperparts sometimes with very fine speckles. Facial disc distinctly rimmed. A Blackish-brown area surrounds dark brown eyes. Erectile ear-tufts very tiny and mostly invisible, set near the center of the forehead. Wings and tail barred tawny and dark brown. In-flight shows prominent dark wrist-patch, visible from above and below; upper primaries with rather plain tawny bases. Below, diffusely vermiculated dusky on paler brown, appearing rather plain (birds from Madagascar more finely barred below). Tarsi feathered; toes partly covered with short plumes; outermost tips rather bare.
Similar species Short-eared Owl is generally pale yellowish-brown with distinct dusky streaking, especially on underparts; eyes pale yellow. Long-eared, Abyssinian Long-eared and Madagascar Long-eared Owls have prominent ear-tufts, yellow to orange eyes, and boldly patterned underparts. Tawny Owl is more boldly patterned, has a broad, rounded head and large blackish-brown eyes (lacks blackish mask), and has whitish outer webs to scapulars. African Wood Owl has barred underparts and a whitish scapular stripe. Eagle owls (Bubo) are larger, with prominent ear-tufts. African fishing owls have bare tarsi and toes. African Grass Owl is larger, dark brown above and pale below, has heart-shaped facial disc with relatively small, blackish eyes and relatively long legs with bristled toes.
VOCALISATIONS Little studied. Very different from all other members of this genus. Most common is a hoarse, grating call, uttered when perched or when circling overhead and clapping wings in the display, sounding like the noise produced by breaking a dry branch by bending it slowly, kerrrrrrrr; being repeated at variable intervals. This vocalization might be the territorial song, often accompanying wing-clapping. Also gives sequences of croaking, raven-like calls on the wing: quarrk-quarrk-quarrk.
Female utters similar but higher-pitched and softer calls. These vocalizations might perhaps express aggression against intruders. Female and fledged young utter far-carrying, wailing hisses with ventriloquially character: shooeeh. If disturbed at the nest, both sexes may fly around with croaking calls and high mewing screams. DISTRIBUTION Africa and Madagascar. An isolated population exists in extreme NW Africa in Morocco. Patchily earth-brown, with a rounded head and distinct pale facial distributed south of the Sahara from Senegambia and Ethiopia to the Cape.
MOVEMENTS In general resident, but partly nomadic within sub-Saharan Africa and an intra-African migrant. Stragglers have been observed in S Iberian Peninsula and The Canary Islands. Displacements are generally caused by responses to food abundance (e.g. rodent plagues) or shortage or are the result of bush fires, floods, etc.
HABITAT Open country from coastal marshes to savanna, with or without scattered trees and bushes; also, inland marshes, moors, and montane grassland, from sea-level up to c.3000m. Avoids extensive long grass, but favors terrain with short vegetation and some patches of long grass or weeds. Locally in rice fields and drainage strips in wooded savanna (‘dambos’), sometimes open areas near or even in human settlements. Absent from forested areas, rocky landscapes, and deserts.
DESCRIPTION A. c. capensis Adult Sexes alike, but males generally paler than females; individually variable in tone. Facial disc pale buff, with the dark brown area around eyes; distinct facial rim dark brown with buff speckles. Ear-tufts earth-brown, very tiny and barely visible, set near the center of the forehead. Upperparts plain earth-brown, crown, and nape finely vermiculated buff, upper tail-coverts barred buff. Primaries with rather plain, pale tawny-buff bases, contrasting with a dusky patch at the wrist; rest of flight feathers barred dark brown and tawny-buff. Tail dark brown, barred pale buff, with whitish tip. Underparts brown, finely vermiculated buff, becoming more uniform pale buff on thighs, belly, and under tail-coverts.
Underwing-coverts buff with dark brown wrist patch, very conspicuous in flight. Tarsi feathered pale tawny-buff; toes covered with pale buffish plumes, leaving tips bare. Juvenile Downy chick covered with buffish down, has pink skin, blackish bill, and pink toes. Mesoptile buff barred brown above; facial disc darker than an adult, with the marked blackish rim. After molt (at c.10 weeks), distinguishable from an adult by buff tips to scapulars and lower back feathers. Bare parts Eyes dark brown. Cere grey-brown. Bill blackish-horn. Bare parts of toes dark brown. Claws blackish.
MEASUREMENTS AND WEIGHT - Total length 31–38cm. Wing 284–380mm, tail 132–186mm. Weight 225–485g.
GEOGRAPHICAL VARIATION - We distinguish three subspecies. A. c. capensis (A. Smith, 1834). Africa south of Sahara. See Description. Wing 285–330mm, tail 132–163mm. Weight: males 243–340g, females 305–376g. A. c. tingitanus (Loche, 1867). Morocco, rarely straggling to S Iberia and Canary Islands. Darker than nominate, with rufous wash and some small whitish markings, especially below. Wing 284–312mm, tail 132–153mm. Weight 310–350g. A. c. hova Stresemann, 1922. Madagascar. Largest subspecies. Underparts more barred and spotted; pale parts of primaries paler. Bill and talons are more powerful than in other races. Wing 322–380mm, tail 176–186mm.
Weight of one male 485g. HABITS Occurs singly or in pairs, sometimes in larger numbers (especially outside breeding season). Mostly crepuscular and nocturnal, but sometimes also active during cloudy days. By day, normally roosts on the ground in a hollow among grass or other vegetation. At dusk or by night, often perches on fence posts, stumps, or tops of bushes watching for prey. May be aggressive near the nest or feign injury in order to distract potential enemies. Flight very similar to that of a harrier Circus.
FOOD - Depends largely on availability. Normally small rodents form the major part of its diet, but sometimes small birds may be predominant; also takes other small vertebrates and insects. Prey includes mice, voles, rats, shrews, young hares, bats, birds up to the size of small ducks and doves, frogs, lizards, scorpions, beetles, grasshoppers, termite alates, etc. Most prey is captured by flying close to the ground with slow but powerful wingbeats, interspersed with fast swerves and hovering, before dropping on to victim; sometimes hawks flying insects, even those attracted by streetlamps in urban areas.
BREEDING - Monogamous and territorial. Sometimes nests in loose colonies. Territories are normally 0.8–2km2 in size, sometimes smaller when the population is denser; in South Africa, nests have been found c.75m apart. Hunting areas of neighboring pairs may overlap. Male claims territory by circling over it, clapping wings and croaking; during courtship, pair-members often fly in wide circles at dusk and on moonlit nights, with wing-clapping and croaking calls (song?). Copulation normally occurs on the ground. A hollow within a patch of tall grass or weeds, often beside a bush and with an ‘entrance tunnel’ from one side, is used for nesting, vegetation often being pulled over by the female to form a canopy. The depression itself is lined with some dry leaves to form a pad (this is probably done by the female but needs confirmation).
In Morocco, a nest was found c.4m above ground in an old corvid nest in a bush, the only known case of a nest not at ground level. Locally, nests in close vicinity to African Grass Owl; in one case the nests were only 20m apart. Nesting normally occurs towards the end of the wet season. The female lays 2–6 (normally three) white eggs (40 x 34.1mm), at intervals of about two days, and incubates alone, starting with the first egg. During incubation she is fed by her mate, who brings food to the nest in its talons, calling as he approaches. He lands at the nest, walks in through the tunnel, and delivers food mostly from bill to bill, but the female sometimes snatches it from his talons. If food is abundant, items may be cached at the nest by the female, or in deposits outside by the male. Incubation lasts 27–28 days for each egg.
Chicks’ eyes open at seven days, and by ten days the facial disc is well developed, already showing characteristic blackish mask and black rim. Up to this age, they are regularly brooded by the female. At 18 days (sometimes as early as 10–14 days), when young still appear downy, they begin to leave the nest and scatter in the surrounding vegetation. An adult defended its chicks by chasing off an African Marsh Harrier Circus ranivorus. Adults carry food directly to their offspring, the young indicating their position by calls and trampling movements. When 30 days old, young have acquired most contour feathers. By 70 days they are fully feathered but are able to fly earlier, by 29–35 days. Both parents care for them for some time before they become independent.
STATUS AND CONSERVATION Uncertain. The NW Moroccan population is declining and endangered by habitat loss and disturbance. South of the Sahara, locally common in years with abundant food. Is affected by bush fires, floods, overgrazing by cattle, and the use of pesticides. Some are killed by road traffic or by entanglement in barbed wire fences.
REMARKS This species, the ecological counterpart in Africa of the Short-eared Owl has been assumed to be a close relative of the latter, but we believe the similarities in ecology and external appearance are due to convergence and not to the relationship. Their totally different vocalizations support this view. In any case, it would be unwise to consider the two as comprising superspecies, and certainly not as members of the same species. The Marsh Owl’s vocalizations, behavior, reproductive biology, taxonomy, and DNA relationships need further study.
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