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Game Ranging / Field Guiding Course
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Birds Copyright
Module # 6 Component # 6
Eagles
Introduction
There are seventeen eagle species in Southern Africa. The group is subdivided into two groups:
The snake eagles are characterised by having unfeathered legs, and except for the Bateleur, are all classed in a single genus: Genus Circaetus. There are five
members of the snake eagle group in the region. Snake eagles generally still hunt from a perch, except for the Bateleur.
The true eagles have feathered legs. Only five of the true eagle species are found in the same Genus - Aquila. There are twelve true eagle species in the region.
The true eagles have large claws and heavy bills and usually hunt from the air. The more common of the species are:
Bateleur (Terathopius ecaudatus) Short-toed Snake Eagle (Circaetus gallicus) Brown Snake Eagle (Circaetus cinereus) Wahlberg's Eagle (Hieraaetus wahlbergi) Tawny Eagle (Aquila rapax) African Fish Eagle (Haliaeetus vocifer) Martial Eagle (Polemaetus bellicosus) Verreauxs' Eagle (Aquila verreauxii)
The other less commonly seen species include:
Western Banded Snake Eagle (Circaetus cinerascens) Southern Banded Snake Eagle (Circaetus fasciolatus) Booted Eagle (Hieraaetus pennatus) Lesser Spotted Eagle (Aquila pomarina) Longcrested Eagle (Lophaetus occipitalis) Steppe Eagle (Aquila nipalensis) Ayres's Hawk Eagle (Hieraaetus ayresii) African Hawk Eagle (Aquila spilogaster) Crowned Eagle (Stephanoaetus coronatus)

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Bateleur - Terathopius ecaudatus
Vital Statistics
Wingspan 180 cm [72 in]
Weight 2 3 kg [ 4 - 6 lbs.]
Preferred prey 66% = Carrion, 33% = generalist hunter
Incubation period 55 days
Clutch size 1 egg
IUCN Status Vulnerable
Nesting site Tree tops, usually Acacia Spp. or other thorn trees
Nestling period 95 - 195 days
Habitat Open Grassland and Savanna Woodland

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Description The Bateleur is arguably one of the most striking of the greater group of eagles.
It is difficult to wrongly identify it, with its red face, legs and feet. This bulky looking eagle is mostly black with grey wing coverlets. It also has a creamy white
patch on its upper back. Its eyes are a deep honey brown and its bill grey tipped, merging to yellow at its base. The bird is also very distinctive in flight, appearing almost tailless.
The juvenile of the species is very different, being mostly light brown. Its face is a
pale greenish - blue, and legs and feet whitish - grey. These characteristics often lead to it being mistaken for the Brown Snake eagle. Progression from first juvenile plumage to full adulthood is a lengthy period, taking seven to eight years, as it
passes through a succession of gradual moults. From the few complete records kept, only about 10 % of juveniles reach adulthood. The reason for this very high
mortality is unknown. The bird was first described by the French naturalist and explorer, Le Vaillant.
Bateleur in French describes an acrobat or tumbler, a possible allusion to its remarkable flight. Its scientific name is a mixture of Greek and Latin and is
translated as marvellous face; "without tail".

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Courtship and Reproduction Courtship within the species involves some spectacular flight displays. In these
flights, the males chase the females. The male who can reach up to 80 Kph [50
mph] in flight dives at the female, who rolls and presents her talons at him. He may then execute several 360 rolls, and start off for her again. This is all accompanied by loud calling by the male, and an odd sound made by his wings that
sounds like a loose sail flapping in the wind.
Nests are situated in large trees, usually 10 to 15 m [33 50 ft] above the ground.
They are built within the canopy, and thus are shaded for most of the day. Although a variety of trees may be used, thorny acacias are favoured. A single egg is laid
from January to April (Southern Hemisphere Summer). Several studies indicate that both sexes incubate the egg. The male will also vigorously defend the nest if an egg or nestling is present by frequently dive bombing any intruders. If the
intruder is still not dislodged, he will settle on the tree between the intruder and nest and make threatening postures by raising his wings.
Incubation generally lasts 55 days, and nestling periods have been observed between 95 and 195 days. Once the young begin flying, they still stay around the
nest for about three months, where they are still fed by the adults.
Juvenile Bateleur

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Flight and Hunting
Although the Bateleur is
capable of rigorous powered flight, like most
birds of prey, they prefer to slowly soar. Also like many of the other raptors, they wait
for warm thermals to gain their lift into the air. Thus,
they may be considered late risers, only taking to wing in mid to late morning. On rainy
or overcast days, they in fact remain grounded, and do
not hunt. Bateleurs are undoubtedly
accomplished hunters, and have been found to take a
very wide variety of prey species, ranging from other birds, to mammals up to 4 Kg
[9 lbs.] in weight. An assortment of reptiles, including the very venomous snakes to which the bird is not immune, is also taken. With all this said however, two thirds
of its diet consist of carrion.
It is this birds high dependence on carrion that has almost confined it to the status of a game reserve species, having totally disappeared from most other regions of the country. This is due to the diminishing number of carcasses and the poisoning
of many others. In many ways, it has suffered the same plight as the vultures in this regard. Ironically the pest species that the poisoning was meant to quell, the
jackal, remains in undiminished numbers after decades of poisoning. Within the conservation areas, the birds have reached quite high densities, and may
remain in the same territory with the same mate throughout their lives.

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African Fish Eagle - Haliaeetus vocifer
Vital Statistics
Wingspan 2.15 m [ 7 ft]
Weight 3 - 4 Kg [6 - 9 lbs.]
Preferred prey Fish specialist, will hunt other vertebrates and take carrion
Incubation period 42 - 45 days
Clutch size 2 eggs
Status Common resident species
Nesting site Trees that are difficult to climb, Acacias, Euphorbias
Nestling period 70 - 75 days
Hunting success 13 % (of each attempt)
Habitat Near water. Natural or artificial

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Description
This raptor is one of the best
known of all the birds of prey. This is due in part to the wide usage of
footage of the bird catching fish from water. This bird is also the easiest to identify. It has a
distinctive white head, breast and mantle, which is offset by a
chestnut brown abdomen and shoulders and black wings.
It also has a short white tail that is often concealed by its folded wings.
Its face and legs are a dull yellow, and its beak is grey. Females can be distinguished from males,
being 10 to 15 % larger when seen perched together, and have a
squarer bib, which is not as deep as the males. Some may confuse it with the American Bald Eagle
but these birds are not African residents.
The juveniles of the species are a
drab brown, with a whitish head. Their bib is also whitish, but streaked with brown. They also
have a white tail that is longer than that of the adults. However, the tail has a conspicuous black terminal band
which is a

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