There are 84
species of Kingfisher which are found worldwide. These
brightly coloured birds with large heads, short necks and
compact bodies, feed on fish, insects and small
vertebrates,
observes Nutan Shukla
An
efficient and unique hunter
LIGHT behaves differently in air and
water. This is why a stick, standing in water, looks
bent. This phenomenon makes it all the more difficult to
catch a fish swimming underwater, but Kingfishers
overcome this problem and do not face any trouble. The
reason is that they have two foveas (depression or pit)
which enable the bird to adjust its eyes accordingly,
both above and below water. As the bird enters from
thinner medium (air) to a denser medium (water) visual
distortion is overcome by the second aquatic
fovea, which compensates for the change in conditions and
ensures that the bird catches its prey successfully.
There are 84 species of
Kingfisher which are found worldwide. These brightly
coloured birds with large heads, short necks and compact
bodies, feed on fish, insects and small vertebrates. They
are usually found in riverine and terrestrial habitats.
The generic name of many
Kingfishers, halcyone, is derived from the name halcyone,
which is a bird in Greek mythology. According to the
story, halcyone, a female character, and her husband,
whom she found drowned on the shore, were turned into
birds by the gods. The birds were called Halcyones.
Mythology says that these
birds built their floating nests on the sea seven days
before the shortest day of the year and brooded on the
eggs for the next seven days. The gods saw to it that
these 14 days were calm and windless, hence the
expression halcyone days for periods of calm,
peace and tranquillity.
All the Kingfishers nest
in holes. It can be a hollow of a tree, burrow in the
mud-bank of a river or in termite mounds. It is
remarkable to note that about 25 per cent of the species
use termite mounds for nesting. Both members of a mating
pair go through a trial-and-error search for a suitable
termite mound, and when one is found, the business of
drilling a tunnel into it begins. The outer coating of
termite mounds are generally hard, and to make the
initial penetration is far beyond the pecking-strength of
the birds.
So these birds adopt a
strategy of attacking the mound, at a particular spot,
one after the other. Their flying attacks make a series
of tiny punctures in the mound. Once a small hole is made
through the outer crust the birds take turns at clinging
to the edge of the hole and enlarging it.
As the hole is driven
deeper the small tunnels inside the mound are exposed and
are immediately sealed by the insects inside, in order to
maintain the required conditions of darkness and humidity
inside the anthill.
This sealing off also
prevents any contact or clash between the insects and the
bird; the passage and nesting chamber are kept open by
the coming and going of the birds. The nest may take
anything up to a fortnight to complete.
When the nesting is
finished and the cavity is abandoned, the termites may
seal the outer opening again. If they do not seal the
nest properly, it may be reopened and used again in
following seasons by the same pair of birds.
The Pied Kingfisher is a
very efficient and unique hunter. Unlike other species,
who sit on the banks of rivers or ponds and wait for the
prey to come to the surface before taking a plunge, it
flies over the water body and scans for small fish or
tadpoles that may venture near the surface. As the prey
is sighted, the bird stops in mid-air and while hovering,
it adjusts its position and drops like a stone from a
height of nine metres submerging completely, and within
seconds it is again out of water with the prey in its
bill.
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