Close to the end of the alphabet now, and
we come to the Yellow-Billed Hornbill.
One of three hornbills in the area, the
Southern Yellow-Billed Hornbill is probably the best known bird of all of our
visitors. Nesting boxes have taken the place of hollowed out tree trunks, and
have allowed two initial pairs to produce many offspring in recent years.
Although the total population does appear
to be decreasing, they are still widespread enough and common enough to be
classified as "Least Concern" on the IUCN red list and there are few
direct threats to their existence. Other
hornbill species in Africa are less fortunate however, and suffer considerable
losses via the demand for bushmeat, and a significant (live, and dead) export
trade to countries such as the United States.
The actual total of southern
yellow-billed hornbills isn't known. They are found in
nine countries in a broad band across Southern Africa, from Namibia in the
west, to Mozambique in the east, and reaching to the southern fringes of
Angola, Zambia and Malawi down to the northern portion of South Africa.
Typical hornbills (like the southern
yellow-billed) have a unique system of nesting, where the female will wall
herself up in the bowel of a tree (or a nesting box), by sealing the entrance
up with mud and bits of plants, leaving only a narrow slit through which
the male can feed her. Once her eggs have hatched, the female breaks out, and
her oldest chick reseals the entrance behind her. Once out of the nest the female
doesn't tend to stray far, and continues to rely on the male to bring her food,
some of which she passes on to the strongest of her chicks. Typically only the
one or two strongest chicks will survive. Hornbills are omnivorous; eating both
plants, small reptiles, and insects.
They are territorial and will drive off
other hornbills in the area. This also
results in them attacking what they believe are other hornbills in the area,
but are in fact their own reflections in vehicle side-mirrors! They have a loud
'tocking' call, and a surprisingly graceful gliding flight.
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