OWLS & FARMERS

Contents Page

Page 3 All about owlsPage 6 South African SpeciesPage 18 Threats facing southern African owlsPage 20 Owls and FarmersPage 22 What the public can do to help owlsPage 23 For your information

Published and printed by the Endangered Wildlife Trust © 2006. Revised 2012.Printing sponsored Anglo Inyosi Coal

ReferencesBarnes, 2000. Red Data Book of Birds of South Africa, Lesotho and Swaziland.Endangered Wildlife Trust, 2005.Barn Owls and bio-control.Hockey, P.A.R., Dean, W.R.J., Ryan, P.G., 2005. Roberts’ Birds of Southern Africa. 7th Edition.Konig, C., Woick, F., Becking, J.H. 1999. Owls: A Guide to the Owls of the World. MacLean, G.L., 1993. Roberts’ Birds of Southern Africa. 6th Edition.Tarboton, W. and Erasmus, R., 1998. Sasol; Owls and Owling in Southern Africa.

All about owlsOwls are one of the most easily recognized bird families, firmly entrenched in folklore and cultural beliefs across the globe. Human views on owls vary from seeing them simply as night-active birds, to being either positive or negative symbols. Owls are not only associated with wisdom and longevity, but also with death, bad luck and evil.

Despite these perceptions, most people have limited knowledge of the fascinating adaptations and indispensable value of these birds. This is largely because of the owl’s ability to operate after dark, when most people are indoors, or not able to see as well as these nocturnal creatures. Owls have several features that enable them to thrive at night, in particular, acute eyesight, excellent hearing and the ability to fly slowly and silently.

Barn Owls in particular are an asset to the farmer. They raise chicks in an on-going cycle, so at any given time they may have several chicks of different ages in their nest. In this way a pair and their offspring use about 3000 rodents per annum. Measured in terms of rodent food, that’s roughly 10 tons of grain saved rather than becoming spoiled or eaten. For farmers who experience excessive rodent infestations, these figureshighlight the importance of choosing a rodenticide product that will not have a negative effect on the owl population!

First published in 2006© Copyright 2006 by the Endangered Wildlife Trust. All rights reserved. The information in this booklet may be used freely but only for non-commercial purposes.Authors: André Botha and Hayley KomenRevised 2012: Zelda Hudson, Design & Layout: Marion BurgerRevised 2016: Design & Layout: Marion Burger

ACKNOWLEDGEMENTSA special thank you to Anglo Inyosi Coal for sponsoring the printing of this booklet which will go a long way towards increasing public awareness around the problems facing owls in conservation. Thanks also to Alan and Meg Kemp for reviewing the booklet.

Photographs used in this publication were taken by André Botha, Wendy Collinson, Matt Pretorius and Shutterstock.

All about Owls

X-ray eyes?

The forward facing eyes of the owls provide them with binocular vision similar to that of humans. Owls however, have very large eyes, excellent for gathering the limited light available at night, but while a tubular shape reduces their weight, it also limits the birds’ field of vision. This is compensated for by an owl’s ability to rotate its neck through up to 270°. Owls may also bob and weave their heads when focusing to enhance their three-dimensional view. Each pupil acts independently so that the owls can see objects in shadows and in bright light simultaneously. So, although they do not have x-ray vision, owls certainly see much better than humans do, especially at night.

How well do they hear?

The owls’ acute hearing has more to do with its ability to pinpoint sound than to detect soft sounds. The part of the brain dealing with hearing is much larger in owls than in most other birds, and owls can detect the direction from where the sound originates very accurately. The owls’ facial disk reflects sounds towards its ear openings, so further enhancing its hearing. In this way, some owls are able to locate and catch their prey in almost total darkness.

Stealth technology in flight

With the exception of Pel’s Fishing Owl, all southern African owl species are capable of virtually ‘silent’ flight. Owls have a large wing surface area compared to body size, while the leading flight feathers have a soft, comb-like edging, allowing them to fly far more quietly than other birds. This talent helps them to better use their acute hearing in flight, and to move in on prey without being heard.

Camouflage

One of the reasons that few people have seen a wild owl is that all species possess excellent camouflage. In addition to cryptically coloured plumage, they roost very quietly and many elongate their bodies to assume the form of a broken branch, further enhancing their camouflage. Species with ear-like tufts will raise these, again improving their camouflage. Despite sometimes perching in exposed places during the day, owls are very difficult to detect.

What does an owl sound like?

Most people associate the typical hooting “hu-huuu” call of species such as the Spotted Eagle-Owl with all owls. In fact, southern African owls have very distinctive calls that make it possible to identify a species without actually seeing the bird. Calls vary from the high screeching of the Barn Owl to the sharp, repetitive whistle of the little Pearl-spotted Owlet. Owls call to communicate with one another, to find a mate and to advertise their occupancy of a territory. In some species, a pair will call in duet.

Owl breeding

All southern African owls lay white, fairly round eggs, different from most other raptors. Owls seem to rely on the camouflage of the incubating parent bird to protect the eggs from detection by predators, especially during the day. At night, the white eggs are easier to detect by the parents when returning from the hunt. Clutch sizes vary from 2-4 eggs, although the Barn Owl can, in seasons of food abundance, lay as many as 19 eggs!

Owls use a variety of nesting sites, ranging from a grassy bowl on the ground in the case of the Grass Owl, to a rocky ledge for the Cape Eagle-Owl, or a natural cavity or hole in a tree for various other species. The Barn Owl shows a preference for man-made structures, such as abandoned buildings or water towers. The smaller, insectivorous owls breed in early summer, while species feeding primarily on rodents breed in winter. Food availability seems to play an important part in determining owls’ breeding seasons.

Food and feeding

Owls catch their prey with powerful feet and sharp talons. Prey is detected either by sight, hearing, or a combination of the two, and is caught by a quick stoop and drop. Prey vary from insects, other invertebrates, rodents, small reptiles, frogs, crabs, bats and other mammals up to the size of a duiker in the case of the Verreaux’s Eagle-Owl. Owls contribute substantially towards controlling rodents and other potentially problematic animals, and are therefore an ally to landowners, in particular grain farmers.

BARN OWL Tyto alba

Afrikaans: Nonnetjie-uil, Tswana: Lerubise, Xhosa: Isikhova, Zulu: umZwelele

Length: 30-33cm

Weight: 220-470g

Identification: A medium sized owl, above tawny and grey with small white spots. The face and under parts are white with fine brown spots from breast to belly. The brown eyes contrast with the pale heart-shaped face. The longish legs are closely feathered and white.

Voice: At least 15 different calls, but mainly a long thin screeching.

Distribution: All continents except Antarctica, widespread in southern Africa.

Status: Widespread and common.

Habitat: Always near a suitable roost on a cliff or in buildings or trees. Often found in association with man.

Habits: Roosts during the day, usually in pairs. Emerges at dusk to hunt by quartering the ground.

Food: Eats mainly small rodents (75-97% of diet), although in urban areas mainly small birds. Also other small prey such as scorpions, geckos, bats, frogs, lizards and termites.

AFRICAN GRASS-OWL Tyto capensis

Afrikaans: Grasuil, Tswana: Lerubise, Xhosa: Isikhova, Zulu: umShwelele

Length: 34-37cm

Weight: 355-520g

Identification: Similar to the Barn Owl, but larger and darker above. Below, whitish with a buff breast. The upperparts and under parts contrast strongly. The face is white to pale brown and the eyes are dark brown.

Voice: Usually silent, but when vocal, mostly a series of high clicking notes or a shrill screeching territorial call.

Distribution: Patchily distributed from southern Cape to Ethiopia.

Status: Numbers declining due to habitat destruction. Vulnerable Red Data species in South Africa with fewer than 5 000 estimated to remain.

Habitat: Long grass, usually near water and wetlands.

Habits: Usually found in pairs or family groups of 4-5 birds. Roosts and breeds on the ground in rank grass. Flushes reluctantly, soon dropping back into the grass.

Food: Mostly rodents (76-98% of diet), especially vlei rats, but also birds, reptiles, frogs and insects.

MARSH OWLAsio capensis

Afrikaans: Vlei-uil, Tswana: Lerubise, Xhosa: iNkovane, Zulu: umShwelele

Length: 36-37cm

Weight: 240-355g

Identification: A medium-sized owl that looks uniform brown from a distance. The facial disc is round and pale brown with a black rim. The creamy white wing bar is distinctive in perching and appears as a pale patch near the wingtips in flight. The owl has very short ‘ear’ tufts.

Voice: A harsh, tearing croak.

Distribution: Widely distributed in southern Africa, but mainly absent from the dry west.

Status: Possibly locally threatened, but otherwise a common and somewhat nomadic resident.

Habitat: Grassland, vleis and marsh edges.

Habits: Solitary or in pairs when breeding, sometimes in groups of up to 75 birds. Sometimes hunt by day, especially when feeding chicks. Breeds and roosts on the ground. Often perches on fence posts along road when not hunting in flight low over the vegetation.

Food: Mainly small rodents, insects and birds, but also frogs, bats and other small animals.

AFRICAN SCOPS-OWL Otus senegalensis

Afrikaans: Skopsuil, Twsana: Lerubisana

Length: 13-18cm

Weight: 60-98g

Identification: A small owl with a grey face outlined boldly in black. The tail is short and the long ‘ear’ tufts are prominent when the bird is at rest.

Voice: High pitched, ventriloquial purring note, somewhat insect-like, repeated at regular intervals.

Distribution: Africa south of the Sahara and adjacent islands.

Status: Sparse to locally common resident in suitable habitat.

Habitat: Almost any woodland, but mainly drier savanna.

Habits: Solitary or in pairs. Nocturnal, roosts by day against the trunk of a tree, blending in very well. Hunts by dropping onto prey from a perch.

Food: Mainly insects, millipedes, centipedes, scorpions and solifugids, also small rodents, birds, lizards and frogs.

SOUTHERN WHITE-FACED SCOPS-OWL Ptilopsis granti

Afrikaans: Witwanguil, Tswana: Lerubisana, Zulu: uMandubulu

Length: 25-28cm

Weight: 150-250g

Identification: A small to medium-sized owl. The white face with a black border, bright orange eyes and prominent ‘ear’ tufts make it unmistakable. Dove grey above with white spots down the sides of the back.

Voice: A rapid bubbling hoot.

Distribution: Widespread in southern Africa in suitable habitat, excluding the south.

Status: Fairly common resident.

Habitat: Woodland, savanna, arid thornveld and riverine bush.

Habits: Solitary or in pairs. Nocturnal, hunts from perch, dropping onto its prey.

Food: Up to 85% rodents, also invertebrates and birds.

PEARL-SPOTTED OWLET Glaucidium perlatum

Afrikaans: Witkoluil, Tswana: Lerubisana, Zulu: iNkovana

Length: 17-21cm

Weight: 60-125g

Identification: The smallest of the southern African owls. No ‘ear’ tufts, but broadly streaked brown on white under parts. The back of the head shows ‘false’ black eye spots.

Voice: Long penetrating whistle, repeated and rising in volume.

Distribution: Africa south of the Sahara except Eastern and Western Cape, south and central Free State and southern Kwa-Zulu Natal.

Status: Common resident.

Habitat: Bushveld, woodland and Acacia savanna.

Habits: Partly active during the day, hunts by dropping onto prey from a perch.

Food: Mainly invertebrates, but also small rodents, frogs, snakes, bats, lizards and birds.

AFRICAN BARRED OWLET Glaucidium capense

Afrikaans: Gebande Uil, Tswana: Lerubisana

Length: 20-21cm

Weight: 115-120g

Identification: Small with a large rounded head. No ‘ear’ tufts. Narrowly barred white or buff. Eyes pale yellow.

Voice: A series of loud, purring notes, but also a series of faster, whistling notes.

Distribution: In southern Africa found in woodlands of northern Namibia, northern Botswana, Zimbabwe, Mozambique, Swaziland and north and east South Africa to Eastern Cape.

Status: Locally threatened but widespread in Mpumalanga.

Habitat: Tall open woodland, mainly along flood plains, watercourses and hill slopes.

Habits: Mostly nocturnal, roosting among tree foliage. Bathes often.

Food: Mostly invertebrates such as beetles, grasshoppers, scorpions, mantids, millipedes, crickets, hawk moths and caterpillars, also small vertebrates such as dormice, lizards, frogs, snakes and birds.

AFRICAN WOOD-OWL Strix woodfordii

Afrikaans: Bosuil, Tswana: Lerubisana, Xhosa: Ibengwana, Zulu: uNobathekeli

Length: 30-36cm

Weight: 250-335g

Identification: White eyebrows and dark-rimmed eyes. Feathers barred buff. Eyes brown with red-rimmed eyelids.

Voice: Main call a series of hoots, each note rising and falling in pitch. Also a single deep hoot or short howl.

Distribution: In southern Africa found in northeastern Namibia, northern Botswana, Zimbabwe, central and southern Mozambique, northeastern South Africa, Swaziland and Kwa-Zulu Natal, patchy westwards to Cape Town and the Cedarberg.

Status: Not threatened.

Habitat: Any densely wooded habitats.

Habits: Territorial pairs. Strictly nocturnal, usually roosting low down.

Food: Insects and small birds, but also centipedes, rodents, frogs and snakes.

SPOTTED EAGLE-OWLBubo africanus

Afrikaans: Gevlekte Ooruil, Tswana: Morubise, Xhosa: Isihulu-hulu, Zulu: isiKhovampondo

Length: 43-47cm

Weight: 540-995g

Identification: A large owl with conspicuous ‘ear’ tufts. Primarily grey and spotted white above, finely barred grey below. The eyes are yellow, seldom orange.

Voice: Deep two-part hoot, pairs often calling in duet.

Distribution: South and central Africa, south of southern Kenya and DRC.

Status: Common resident.

Habitat: Rocky areas, woodland, forest edge, savanna, semi desert, towns and cities.

Habits: Solitary or in pairs. Nocturnal and hunts from perch dropping onto prey. Commonly perches on fence posts or telephone poles. Often hunts insects in flood lights.

Food: Mostly invertebrates, but also birds, reptiles, mammals up to the size of hares, bats, snails, crabs, millipedes and snakes.

CAPE EAGLE-OWL Bubo capensis

Afrikaans: Kaapse Ooruil, Zulu: isiKhovampondo

Length: 50cm

Weight: 1000-1200g

Identification: Large owl with ‘ear’ tufts. Blotched tawny, particularly obvious on the neck. Eyes orange.

Voice: Deep double or triple hoot.

Distribution: In southern Africa found in mountainous and rocky habitats of Namibia and Zimbabwe, the extreme west of Mozambique, South Africa, Lesotho and western Swaziland.

Status: Not threatened.

Habitat: Rocky outcrops, cliffs and gorges with open grass or scrub nearby.

Habits: Emerges occasionally at dusk, in the rays of the setting sun. May sunbathe in the early morning.

Food: Mostly mammals, such as hyraxes, rock rabbits, cane rats, Klipspringer and Common Duiker lambs. Also Springhares, shrews, free-tailed bats, lizards, insects, crabs, spiders and birds.

PEL’S FISHING-OWL Scotopelia peli

Afrikaans: Visuil

Length: 63cm

Weight: 2014g

Identification: Very large owl with upperparts rufous and narrowly barred black. No ‘ear’ tufts, with large dark brown eyes.

Voice: Deep humming hoot, often preceded by a series of grunts.

Distribution: Major river systems of sub-Saharan Africa, but not in dense lowland forest.

Status: Vulnerable.

Habitat: Extensive swamps and broad tropical rivers with riparian trees.

Habits: Members of pairs often close together. Emerges at dusk. Wades into water to bathe.

Food: Mainly fish, but also young Nile crocodiles and frogs.

VERREAUX’S EAGLE-OWL Bubo lacteus

Afrikaans: Reuse-Ooruil, Tswana: Morubise, Xhosa: Ifubesi, Zulu: isiKhova

Length: 58-65cm

Weight: 650-3200g

Identification: The largest South African owl, finely barred above and below with no heavy blotching. The face is pale and boldly outlined in black. The pinkish eyelids are conspicuous with obvious stubby ‘ear’ tufts.

Voice: Irregular, loud, gruff hooting.

Distribution: North of the Orange River in southern Africa, extending across to the east coast of northern KwaZulu Natal and down the coast into the Eastern Cape.

Status: Common to uncommon.

Habitat: Woodland, savanna and tree-lined watercourses.

Habits: Solitary, in pairs or as family groups. Mostly nocturnal and roosts in large trees by day.

Food: Medium-sized mammals such as monkeys and small antelope, birds up to the size of korhaans, reptiles, frogs and insects.

Threats facing southern African owls

Although they have a number of natural predators, the threats facing owls are mostly due to human action.

Poisoning

Many owl species feed on rodents thus contributing towards a balanced ecosystem. Incorrect use of rodenticides can therefore have severe consequences for owls, killing not only the rodent, but also its predators.

Collisions

Roads are distinct ecological systems with unique features distinguishing them from adjacent lands. The road reserve running alongside a road often forms an ideal ungrazed habitat for rodents and other wildlife. Minimal disturbance of this often grassy area ensures excellent cover for prey species, while a good food supply is available when drivers throw garbage out of car windows, or when grain is split on the road during transportation. Furthermore, fences and telephone poles alongside the road are ideal perches for raptors and other birds. As nocturnal hunters, owls are particularly susceptible to traffic collisions, since the headlights of oncoming cars dazzle the birds so that they are unable to move out of the way in time.

A flying owl does not look directly ahead, but instead will scan the area a distance off in search of prey. Natural obstacles such as trees are easy to see, but the thin strands of a barbed wire fence are less visible. Owls and other birds therefore often fly into the top strands of these types of fences where they are caught in the barbs, often dying slow deaths through dehydration, starvation and shock.

Habitat destruction, disturbance and fragmentation

Destruction of prime owl habitat to make way for agriculture, development and forestry is an ongoing problem. Some species are able to adapt surprisingly well to these environmental changes, however others are severely threatened. As development continues, owl habitat becomes more fragmented, isolating populations with the threat of loss in genetic diversity. This can cause a population to become less adaptable and should a major change occur, the population is more susceptible to extinction.

Threats facing southern African owls

Fire plays an important role in many natural ecosystems, preventing bush encroachment and maintaining the build-up of moribund vegetation. This ensures that serious fires do not occur as a result of excess fuel. However, where good fire management is not practised, uncontrolled fires can cause serious threats to owl, in particular ground-breeding species such as the African Grass-Owl. Overgrazing can similarly reduce suitable habitat for species such as the Marsh Owls and African Grass-Owls, to the point where they simply disappear from an area.

Direct human impact

In Africa there is a traditional belief that owls are bad luck. Many people still follow this belief and will kill, chase or maim owls out of fear. The use of owls in traditional medicine has also been documented to some degree; however there is much we still need to learn about this.

People often come into direct contact with owls when they find a chick on the ground, seemingly having fallen from the nest. These flightless youngsters are, however, still being cared for by their parents outside of the nest until they are able to look after themselves. Unless there are obvious injuries or the chick is in immediate danger by a predator, it is best to leave it alone. Caring for young or injured owls is a highly specialized skill that should only be attempted by qualified people, while the stress caused when a young bird is handled could be enough to kill it.

The following rehabilitation centres are able to attend to injured owls:

Northwest De Wildt Cheetah and Wildlife Trust, 012 504 1921KZN Raptor Rescue, 031 785 2000 or 082 359 0900Western Cape Eagle Encounters, 084 584 3684 or 082 462 5463Limpopo Moholoholo Wildlife Rehabilitation Centre, 015 795 5236Mpumalanga Dullstroom Bird of Prey Centre, 013 254 0777 or 072 378 8562

Or contact the Birds of Prey Programme on 011 372 3600.

Owls and Farmers

The Barn Owl is arguably the most effective rodent predator on earth. Barn Owls are increasingly called on by farmers to help control rodent plagues when these threaten to decimate their cash-crops. In areas of high intensity agriculture around the world, particularly in cereal croplands, but also in rice paddies and fruit orchards, there is a growing trend away from the use of expensive and damaging toxic chemicals to eradicate rodents, and towards a much cheaper, more sustainable and, crucially, more efficient ‘bio-control’ agent – the Barn Owl.

Barn Owls are cavity-nesting birds which under natural conditions breed in cracks in rock faces and holes intrees. They have adapted well to using recesses in buildings, particularly inrodent-rich environments. In farming areas with pest rodent problems, Barn Owl numbers can be increased by providing suitable nest boxes, spread evenly across the farmland, for occupation and use by breeding owls. Once in residence, the owls will hugely increase the levels of predation pressure on the nocturnal rodent population, and reduce the rodent pest factorin the area both by killing and eating large numbers ofrats and mice and by limiting the extent to which there maining rodents are prepared to venture away from protective cover.

For more information about owl nest boxes, contact the Birds or Prey Programme on (011) 372 -3600, e-mail raptor@ewt.org.za.

What the public can do

• Be alert to the possibility of hitting an owl on a road.• Stay within the speed limit and slow down when driving after dark to ensure that you can react safely and timeously.• If an owl is encountered on a road, it might not move out of the way because the bright headlights of a car temporarily blind it. In this case, slow down, dim the headlights and hoot if the bird still does not want to move off.• Avoid littering, as excess food will attract rodents to the road reserve, with owls following.• If a dead owl is seen lying on or next to the road, report it to the EWT’s national owl road mortality database at www.ewt.org.za.• Leave young owls alone as the parents will most likely still be taking care of them, even if they are no longer in the nest.• Inform yourself about the environmentally friendly use of pesticides. More information is available from the EWT on 011 372 3600.• If an injured owl is found, call the nearest wildlife rehabilitation centre. A list of rehabilitation centres is available on page 19.

For your information

The Endangered Wildlife Trust was established in 1973 and is registered as a Non-profit Organisation. The EWT fills the key niche of on-the-ground conservation action with the focus on identifying the key factors that threaten biodiversity and to develop mitigating measures to reduce these.

Private Bag X11, Modderfontein, 1645, Gauteng, South Africa. Tel (011) 372-3600, Fax (011) 608-4682.

Birds of Prey Programme

A Specialist Programme of the Endangered Wildlife Trust The Birds of Prey Programme (BoPP) is committed to the conservation of the natural populations of diurnal and nocturnal raptors in southern Africa by the initiation and support of research, conservation and education programmes based on sound scientific and conservation principles. A number of conservation projects operate under the auspices of the BoPP all over southern Africa. The BoPP publishes the journals Gabar and Vulture News and the electronic newsletter The Eagle’s Eye. National and international collaboration with other conservation organisations strengthen the work of the BoPP.

Private Bag X11, Modderfontein, 1645, Gauteng, South Africa. Tel (011) 372-3600, Fax (011) 608-4682,

E-mail raptor@ewt.org.za.

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Address: Building K2, Pinelands Office Park, Ardeer Road, ModderfonteinPostal Address: Private Bag X11, Modderfontein, 1645

Tel: +27 11 372 3600Fax: +27 11 608 4682

E-mail: raptor@ewt.org.zaWebsite: www.ewt.org.za