Hamerkop
Scopus umbretta
Bird
| At a Glance | |
| Wingspan | 90cm height approx. 56cm |
| Mass | 500 gram |
| Lifespan | 20 years |
| Conservation Status | Least Concern |
Description
A very unique looking bird, with dull brown plumage and a distinctive anvil-shaped head and backward pointing crest.
Behaviour
The hamerkop's behaviour is unlike other birds. One unusual feature is that up to ten birds join in "ceremonies" in which they run circles around each other, all calling loudly, raising their crests, fluttering their wings. Another is "false mounting", in which one bird stands on top of another and appears to mount it, but they may not be mates and do not copulate.
These birds are compulsive nest builders, constructing three to five nests per year whether they are breeding or not.
Diet
It eats mainly the adults and tadpoles of platanna frogs, which have a very similar distribution to the Hamerkop, suggesting that it is dependent on them for food. It also eats other frogs, small fish and insects, using a variety of foraging techniques, such as wading through the water and stabbing prey, still-hunting at the water's edge or pouncing on prey from the air.
Breeding
Monogamous solitary nester.
The nest is usually built by both sexes, and rarely a group of up to seven birds, with construction taking anything from 40-43 days to several months. It consists of a uniquely-shaped, large pile of material with an interior chamber and entrance low down on the side. At first, a supporting structure of sticks similar to an inverted pyramid is laid down. The walls are then built by interlocking twigs and finally the whole structure is covered with stalks, sticks, reeds, grass and twigs, while it often decorates it with a variety of both natural and man-made materials, including cardboard, plastic, leaves, bark, aloe stems and stones and wool. It is typically placed in a tree over or next to water.
The clutch consists of three to seven eggs
Distribution
This is a very widely distributed but not common bird and can be found in south-western Arabia, Madagascar and sub-Saharan Africa. It is locally common across southern Africa wherever there is water close by so it is scarce to absent in the arid western region.
Habitat
It generally favours the shallow margins of lakes, pans, swamps, rivers, marshes, streams, seasonally flooded ponds and even small puddles in gravel roads.
Threat
Nest predators such as snakes and monitor lizards are the largest source of hamerkop predation. An stimated 50% of all eggs and 30-40% of chicks are lost to predation, but if an individual survives to adulthood, it has few predators.
Local Information
Memorial Park
They have been nesting in the swamp forest in the park for many years now. The nest has been rebuilt many times.
Interesting Facts
Its middle toenail has a rough comb-like edge (a pectinate toe), as do the herons (this toe is used to groom its feathers)
It soars with its neck stretched out like a stork or ibis, but during flapping flight, it coils its neck back so that it resembles a heron.
Features prominently in Xhosa and other folklore; regarded in awe and not molested.
There is a San painting of a Hamerkop in Zimbabwe.
Sound
A sound clip is available on SoundCloud.