Tuesday, 19 March 2013

African Fish Eagle

The African Fish Eagle is a large bird; with the female weighing 3.2-3.6 kg (7-8 lbs) is larger than the male, which weighs at 2-2.5 kg (4.4-5.5 lbs). Males usually have a wingspan of about 2 m (6 feet), while females have wingspans of 2.4 m (8 feet). The body length is 63–75 cm (25–30 in). The adult is very distinctive in appearance with a mostly brown body and large, powerful, black wings. The head, breast, and tail of African Fish Eagles are snow white, with the exception of the featherless face, which is yellow. The eyes are dark brown in colour.
The hook-shaped beak, ideal for a carnivorous lifestyle, is yellow with a black tip. Breeding season for African Fish Eagles is during the dry season, when water levels are low. African Fish Eagles are believed to be monogamous - in other words, they mate for life. Pairs will often maintain two or more nests, which they will frequently re-use. Because nests are re-used and built upon over the years the nests can grow to be quite large, some reaching 2m (six feet) across and 1.2 m (4 feet) deep. The nests are placed in a large tree and built mostly of sticks and other pieces of wood. The female lays 1 to 3 eggs, which are primarily white with a few reddish speckles. Incubation is mostly done by the female, but the male will incubate when the female leaves to hunt. Incubation lasts for 42 to 45 days before the chicks hatch. Like other sea eagles, the African Fish Eagle has structures on its toes called spiricules that allows it to grasp fish and other slippery prey.
The African Fish Eagle is most frequently seen by the rivers, lakes and coasts of Africa south of the Sahara. It is most frequently seen sitting high in a tall tree from where it has a good view of the stretch of river, lakeshore or coastline which is its territory. Near a lake with an abundant food supply, a pair may require less than a kilometre square of water to find enough food, whereas next to a small river, they may require a stretch of 25km or more. The breeding display consists of much soaring and calling with very occasional claw-grappling.
Their main food is fish, sometimes dead, but mostly caught live. Catfish and lungfish are among the most frequent. They also catch and eat some water birds, including their young. The birds most frequently taken include ibis, waterfowl such as ducks, small turtles and terrapins, baby crocodiles, greater flamingos and lesser flamingos, lizards such as Nile Monitors, frogs storks, herons and spoonbills. They also eat some carrion. Live caught fish account for about 90% of their diet. Widespread in South Africa, the African Fish Eagle is particularly common in and around some of the Great Rift Valley lakes such as Lake Baringo, Lake Bogoria, Lake Nakuru and Lake Naivasha among other lakes. The African Fish Eagle has two distinct calls. When near the nest its call is more of a "quock" sound - the female being, in all cases, a little shriller and less mellow than the male.

JBA- Kenya birdwatching safaris