Grand-duc africain

Taxonomie

Nom scientifique

Bubo africanus

Autorité

(Temminck, 1821)

Ordre

Strigiformes

Famille

Strigidae

Genre

Bubo

Répartition et habitat

Spotted eagle-owls are the most common species of owl found in southern Africa. They have a healthy population in most parts of the region. They are often referred to as urban owls and will live in close proximity to human habitation. They occur throughout sub-Saharan Africa and the Arabian peninsula. They can also be found in thorn savanna and in suburban gardens, such as the outskirts of Harare, Zimbabwe.

Migration

Resident species

Comportement

The calls are generally typical, musical eagle-owl hoots. Generally the male call with two hoots: "Hooo hooopoooo" and the female answers with three, with less stress on the middle note: "Hooo hoo hooo". The young do not hoot till effectively adult, but from a very young age they will hiss threateningly and snap their beaks castanet-like if alarmed. These sounds they make throughout life, generally in a threatening attitude with head down and wings spread sideways to present their upper surfaces forward, umbrella-like. They might present such behaviour either as a challenge to rival owls or when defending nest or young against enemies. The young at least have a whickering call of protest or annoyance when handled. In a comfortable social situation the youngsters have a soft croaking "kreeep" that they are prone to repeat at regular intervals of a few seconds. If they suspect that they have lost their company, the calls increase in frequency and they are likely to go hunting for their companions. Chicks and adults will snap bills, hiss and chitter to threaten or distract.<p>As with all owls this species, when detected, is subject to daylight harassment by local birds. In the Gauteng area its main and extremely loud tormentor is the grey loerie, respite only coming at dusk. Spotted eagle-owls are regular bathers and during summer thunderstorms may be seen on tree limbs or on the ground with spread wings.<p>They prefer rocky areas, favouring to roost in open areas such as on the ground, rocky outcrops and tree crowns.

Conservation

They are not globally threatened, and are often the most common owl species in their habitats.<p>It is illegal to capture or keep any indigenous owls in South Africa without the necessary rehabilitation permit issued by the Department of Nature Conservation. Specialized care is required in captivity consisting of a balanced diet with the correct ratio of calcium to phosphorus and specific husbandry needs that should be met. If raised on the incorrect diet, owlets suffer malnutrition of various types, including metabolic bone disorder (MBD) which causes poor bone formation and could lead to their death. Specialized release methods are applied to integrate captive-raised owlets back into the wild.<p>Car collisions, electric wires, persecution, secondary poisoning and parasite infections such as Trichomonas gallinae are the major causes of mortality. Juveniles and newly fledged birds are particularly vulnerable.

Tendance de la population

stable