[This was written by Fran Siebrits and published online by CapeNature, 2012]
Bird of the Year is one of several initiatives by BirdLife South Africa aiming to create awareness about birds, their habitat and conservation. A much loved king of the sky, it comes as no surprise that the mighty African fish eagle is Bird of the Year for 2012.
It’s the sound of Africa … that unmistakeable call of the African fish eagle graciously demands attention and connects with many people. It is synonymous with freedom, space, clarity, power, nature and the warmth that people living on African soil feel when thinking of home.
The African fish eagle is one of the most widespread birds of prey south of the Sahara and is officially acknowledged by many African nations. It is the national bird of Zambia and Zimbabwe, while it sits in the Coat of Arms of Namibia, South Sudan and again Zambia.
Its scientific name, Haliaeetus vocifer, stems from ancient Greek - halieos meaning fisherman, aetos meaning eagle and vocifer referring to its loud vociferous call. It is found in all environments where water occurs. A very distinctive bird in flight, the white head, neck, upper belly, and tail contrast sharply with the chestnut and black body feathers.
Juvenile African fish eagles are mottled in colour and scruffy in appearance, often confused with other raptors. The striking adult plumage is only obtained when these birds reach an age of four or five years old. Fully grown, males weigh a humble 2,2 kg on average, compared to the impressive 3,4 kg of females.
As with most birds of prey, African fish eagles are territorial. Because their main source of food is fish, they are reliant on seasonal environmental conditions. If there is a drought or flood one particular year, they are flexible enough to relax or adjust the boundaries of their territory to best suit their dietary requirements.
African fish eagles are often spotted in mating pairs near fresh water habitats such as rivers, dams, lagoons and even estuaries. When not in flight, they perch on trees alongside water bodies, watching tentatively for their next meal. Trees are also important roosting and nesting sites in the dry breeding season.
Males, which have a more mellow yet higher pitched call than females, are extremely vocal at the beginning of the breeding season when they attempt to impress their lady. The head is flung back in call, whether from a perch or in flight. Flight displays are spectacular this time of year with the pair ascending higher and higher in ever decreasing circles, calling in duet every so often.
A nest can take three months to build, but is at least reused for many years thereafter. They mate for life, i.e. are monogamous, and repairs to the nest may be done each year so that eventually there is a mass of two metres wide and deep. To ensure fertilisation, the breeding pair mate almost daily, hence the importance placed on a comfortable (and literal) love nest.
Although they can hunt at any time of the day, this activity usually occurs in the early morning and takes about two hours of their day. Fish make up 90% of their diet, while the other 10% consists of young water birds or carrion. They are able to snatch fish weighing 1,5 kg, carrying them off in flight. Anything heavier and weighing up to 3 kg (that’s roughly the same mass as their own body) is caught and ‘planed’ across the water onto shore. It takes an average of eight strikes for a successful meal.
Photographs by Jackie Fox
But if all this hunting is too much effort, African fish eagles steal prey from other birds; this behaviour is known as kleptoparasitism. Goliath herons, for example, lose a percentage of their catch to these cheeky yet ambitious raptors.
This leisurely lifestyle allows the African fish eagle to live for about 20 years, real royalty under the African sky.
One of the most magnificent events to witness is an African fish eagle capturing its prey of an oblivious fish just below the surface of the water. Having spotted what is to be its next meal, this powerful eagle plunges towards the water at speed from its perch or from flight. With the grace of a ballerina, only its bare talons break the surface of the water, snatching up the unfortunate slippery morsel and leaving behind a mere ripple.
The action, the excitement, the speed, the unheard scream, the raw tension of survival, the animalistic instinct, the magnificence … is all over in a matter of seconds. And you are left in silent awe.
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