The Hamerkop - Mmamasiloanoka

The Hamerkop is a rather nondescript bird, with drab, brown plumage, the only really distinguishing physical feature being the rounded crest which gives the bird’s head a hammer-like appearance – and hence the name Hamerkop (literally, hammer-head). It is generally unobtrusive, and is usually seen standing motionless in shallow pools of water, apparently gazing vainly at its less-than-beautiful reflection (or so one African saying would have us believe!).

Despite its innocuous appearance, it is regarded with some suspicion by many people and has numerous superstitions associated with it. What is it that sets this bird apart from all others in this regard? It seems the most unlikely candidate to have inveigled its way into African culture and folklore, but wherever it occurs on the continent, there are stories, proverbs and superstitions about it. Most of these seem to relate to its unusual breeding behaviour, and so it is here we must look if we are to understand how this bird has become a legend throughout Africa.

One peculiar behaviour which has puzzled ornithologists, and intrigued other observers is the birds’ bizarre ritual of false mounting – one bird of a pair flies up onto the back of the other, calling loudly and flapping its wings to steady itself, to all intents and purposes preparing to mate. However, after balancing in this position for a short while, it deliberately hops off and is surmounted by the other bird! On some occasions there may be three birds involved in this balancing act, each taking its turn to be cock of the walk. This odd behaviour is just a prelude to the rest of the breeding cycle, which is equally strange.

No-one knows why, but the Hamerkop’s nest is an enormous oven-like structure built in a major fork of a tree, or sometimes on the edge of a rocky kopje, usually near water. The nest is round in shape, with a diameter of about 2 metres, and is built mainly of sticks, although just about anything available is added to the top – a nest that had fallen down in Zimbabwe was adorned with (among other things) a pan brush, a broken cassette tape, a glove, a plastic cup, two socks, one piece of glass, a plastic comb, a piece of leather belt, four bits of stocking, seven bits of hosepipe, ten plastic bags, six bicycle tyres and one pair of underpants (male)! The presence of these ‘decorative’ items (especially human artefacts) has no doubt contributed to the awe with which the Hamerkop is viewed by many people, since traditional doctors have a similar practice of displaying, outside their homes, personal items of people being ‘bewitched’. This aspect of the Hamerkop’s behaviour therefore has decidedly sinister overtones! That notwithstanding, the nest is remarkable for its size alone – the finished product can weigh between 25 and 50 kilograms and contain 8,000 individual pieces of material. It takes anything from 6 weeks to a few months of hard work by both sexes to construct, and can easily support the weight of a man.

A Hamerkop gathering nesting material – it may collect 25 to 30 such beaksful in an hour (Photo: P Hancock)

The nest has a single, well-insulated, mud-plastered chamber in the centre where the eggs are laid, despite a persistent belief by many people that it is three-chambered (the first is reputed to be dirty and filled with the remains of frogs, the second clean, where the eggs are laid, and the third a sort of day-room!). The female may lay a clutch of up to nine eggs (although not all will hatch) and this is a massive outlay of energy, comprising as it does some 25% of the female’s bodyweight. It is thought that the nest provides warmth and protection for the chicks while their parents are foraging for their specialised diet of Platanna frogs, but it is not clear whether this is really true. One thing is for certain though, and that is the nest is a highly sought-after abode, and is frequently taken over by various other birds and even reptiles. It is very common, for example, for Barn Owls to oust the Hamerkops as soon as the nest is complete; Egyptian Geese too, are hole-nesters and find the Hamerkops’ abode a surprisingly comfortable fit. Small raptors such as Dickinson’s Kestrel breed on top of the Hamerkop’s nest, and may do so while the owners are resident inside. This mutually acceptable arrangement however doesn’t extend to the much larger, predatory Verreaux’s Eagle-Owl – having one of these on your roof (if you are a Hamerkop) is decidedly intimidating.

A Hamerkop perched atop its enormous nest

An interesting outcome of this nest piracy has been the derivation of a Setswana proverb “Bopelonomi bo bolaile Mmamasiloanoka” – kindness killed the Hamerkop! To the uninformed observer, it may appear as though the Hamerkop has been working itself to death to provide a variety of other creatures with top class accommodation, but in reality, they are all squatters taking ‘illegal’ occupation of the Hamerkop’s abode!

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