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Size and Weight: Length is about 70 cm (2.3 feet); Wingspan
up to 2.1 m (6.9 feet); Males weigh up to 3000 gms (6.6 lbs).
Females are slightly larger, weighing up to 3600 gms (8 lbs).
Diet: Ninety percent of the African Fish Eagle's diet
is fish, mostly taken live. They have been known to scavenge or
rob other birds of their prey or to hunt waterbirds and small
mammals when fishing is poor. Fish up to 1 kg (1/3 their body
weight) can be carried though smaller fish are more common. These
birds have been noted catching and eating flamingo as well.
Habitat and Distribution: The African Fish Eagle ranges
throughout sub-Saharan Africa along large rivers, lakes and
estuaries. It tends to stay in the same small territory within
a wetland if the conditions are stable.
Status in the Wild: Throughout most of Africa, the African
Fish Eagle is common and has become a symbol of African wildlife.
Where food supplies are good, this species is gregarious and may
be found in large groups of 60 or more. The status of the African
Fish Eagle is stable, but they are vulnerable to indirect harm
from poisons and pollutants in aquatic systems.
Status in Captivity: ISIS (2002) lists the World Captive
population at 31 birds, and the North American population at 12
though these figures hardly seem accurate knowing the number of
individuals being presented in educational bird programs throughout
the country and the world.
Habits and Adaptations: The African Fish Eagle is a strong,
graceful flier able to lift a 3 or 4 pound fish from the water's
surface. It is commonly seen perched in tall trees overlooking
the water or soaring overhead. Spending most of their time perched,
they seem to favor specific perches that they return to after
hunting. They hunt using short flights and are not opposed to
eating carrion or stealing prey from other birds of prey. The
African Fish Eagle has a distinctive loud call, reminiscent of
a common gull, which it gives while throwing its head backwards
to touch the middle of the back.
Breeding and Maturation: The African Fish Eagle attains
its adult plumage at about age four, going through a progressive
series of molts where the brown head feathers are replaced with
white. Adult pairs remain in close proximity throughout the year.
Eggs are laid from April through June. The stick nests are usually
high in trees or occasionally on a cliff. A nesting pair returns
to the same nest year after year, with nests attaining diameters
of 6 feet or more. Some pairs have up to 3 nests. Clutch size
is most commonly 2 and eggs are laid at roughly 3 day intervals.
Incubation starts with the first egg and is by the female, lasting
42-45 days. The young hatch asynchronously and sibling aggression
often results in the death of the smallest chick(s). First flight
occurs about 70 days after hatching. Young may remain around the
nest for several months while they learn to hunt and can probably
successfully catch prey 2 months after fledging.
Lifespan: African Fish Eagles can probably live up to
15 years in the wild and perhaps up to the mid 30s in captivity,
based on records for other commonly held captive species.
Conservation Issues: Fortunately, African Fish Eagles
are important icons symbolizing Africa's wildlife. They are well
recognized and sought after by tourists and are important in bringing
tourism dollars into Africa. Being high on the food chain and
depending heavily of fish makes them vulnerable to water pollution.
Bibliography
Brown, L. and Amadon, D. 1968. Eagles, Hawks and Falcons of the
World. Country Life Books, Great Britain.
Tarboton, W. 1989. African Birds of Prey. Cornell University
Press, Ithaca, NY.
Photo: by Neil Franey for the Minnesota Zoo
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