Verreaux's Eagle-Owl

The Verreaux's Eagle-Owl (*Bubo lacteus*) is a member of the family Strigidae. This species is widespread in sub-Saharan Africa. A member of the genus *Bubo*, it is the largest African owl. This eagle-owl is a resident primarily of dry, wooded savanna. Verreaux's eagle-owl is mainly grey in color and is distinguishable from other large owls by its bright pink eyelids, a feature shared with no other owl species in the world.

Description

Verreaux's eagle-owl are gray, with light and fine brownish vermiculations on the underside. The back is more solidly light brown with white spots on the shoulder. The oval facial disc is paler, sometimes ranging into a whitish color, than the rest of the front side of the bird with strong black borders bracketing either side. One other feature that adult Verreaux's eagle-owls in good light are its pink eyelids.

Voice

The call of the Verreaux's eagle-owl is the deepest of any extant owl species and one of the deepest bird calls in the world, averaging slightly deeper than the calls of the Blakiston's and brown fish owls. The calls of Eurasian eagle-owls are less deep but are possibly louder and farther carrying. The male's song is a deep *gwok, gwok, gwonk-gwokwokwok gwokwokwok gwonk*. The depth and quality of the song makes confusion by sound more likely with a leopard than any other bird.

Behaviour

Verreaux's eagle-owls are nocturnal birds and roost by day in trees, with large, shaded horizontal branches of tall, old trees being preferred.

Diet

Verreaux's eagle-owl is considered an avian apex predator, meaning it is at or near the top of the food chain and healthy adults normally have no natural predators. In many known aspects of its hunting behaviour, it is typical of the members of the genus *Bubo*. This species hunt predominantly in early evening, however they have been observed to swoop on prey during daylight. The owls fly to a different perch from their daytime roost to use as their habitual hunting perch. Verreaux's eagle-owls mainly hunt by gliding down on their prey from a perch. However hunting on the wing has been reported, even of flying insects. On occasion, they hunt by flying low over a bush to catch prey by surprise or dash on the wing into dense foliage or through forests to catch a galago or other prey item.

The prey most often associated with Verreaux's eagle-owl are hedgehogs. The two known hedgehog prey species taken are the four-toed hedgehog, in the north and the southern African hedgehog in the south. When capturing hedgehogs, the eagle-owl descends silently with its soft-comb wings and ambushes the hedgehog by imbedding its talons about the face. After death, the hedgehog is skinned of its prickly back before being consumed by either the eagle-owl itself or the young at the nest. This may result in over a dozen hedgehog skins being found around Verreaux's eagle-owl roosts near their nests.

In general, the diet of Verreaux's eagle-owl is seemingly random and highly variable. Eagle-owl species from temperate zones may have no choice but to predate rodents which are rather small and this may require a nesting pair to capture up to a dozen rodents nightly. In Kenya, the most often recorded prey locally were *Tachyoryctes* mole-rats, however these were recorded only slightly more often than other genera or species, including non-mammals. Some larger rodents they've hunted have included the cape ground squirrel, The Gambian pouched rat, and th lesser cane rat. The largest known rodent prey is the South African springhare

Many other mammals taken as prey by Verreaux's eagle-owl are seemingly any encountered except the much larger species, especially those that show a propensity for nocturnal or crepuscular activity. This species has hunted bats. Lander's horseshoe bat, the smallest known prey species known for this eagle-owl, to *Rousettus* fruit bats. Most other mammalian prey recorded or inferred as hunted by Verreaux's eagle-owl tend to be considerably larger. Both the scrub hare and the cape hare have been reported as food.

So far as is known, Verreaux's eagle-owl is the only living owl who preys upon multiple species of primate. Multiple cases of predation against galagos have been reported, unsurprisingly as they represent all nocturnal primates in Africa. Known galago prey species have ranged from the Thomas's bushbaby to the brown greater galago. Monkeys are also predated opportunistically. Particularly often reported in foods of the Verreaux's eagle-owl as primates go is the vervet monkey. Incidents of successful predation have included vervets that were half-grown, which the eagle-owl was able to fly off with (despite being about as heavy as the eagle-owl itself), and an adult vervet which an eagle-owl took on the ground and subsequently dismembered. However, considering the formidable gauntlet of predators that vervet monkeys face, the Verreaux's eagle-owl is one of its more minor predators and attacks on them may be considered incidental, due in part to the monkey's primarily diurnal activities.

Among mammalian carnivores the bulk of predatory incidents have reportedly involved mongooses. Common, social species from savanna-edge such as the yellow mongoose and the meerkats have been attacked, as well as larger, shy forest dwellers such as the Jackson's mongoose An adult Meller's mongoose which was taken by a Verreaux's eagle-owl on the wing after the aforementioned half-grown vervet monkey. Other smallish carnivores known to fall prey to Verreaux's eagle-owls include the African striped weasel and its larger cousin, the striped polecat, which in one nest from the border of the Kalahari represented the sole prey species for a pair of eagle-owls.