Feature Article
RAHUL ROHITASHWA & D.N. CHOUDHARY
Brahminy Kite
T
HE bird kingdom is replete with deadly
hunters that swoop on their prey
unnoticed and in a flash. Power,
strength, amazing agility and a keen sense
of observation are some characteristics
that mark the “Birds of Prey ” as they are
called.
Also known as “Aerial Hunters”, they
are equipped with a sharp hooked beak
and deadly curved claws known as talons,
which bring swift death of their victims. In a
more specialized sense this expression
refers to the members of the order
Falconiformes. Sometimes the owls
grouped under the order Strigiformes are
also considered as Birds of Prey. The term
‘Raptors’ is also collectively used for Birds
of Prey.
There are about 295 known species
of raptors worldwide. They hunt across a
huge range of habitats, from mountains to
rainforests. Generally they are distinguished
by the type of prey they consume –
mammals, reptiles or other birds. However,
it is ver y difficult to draw a clear-cut
demarcation based on their food and
feeding diversity. A number of falcons feed
mainly on insects. The snail kite of Florida
feeds mainly on snails. Ospreys mainly live
on fishes. Great winged acrobats like
Peregrine falcons catch other birds in midflight with amazing agility.
So, the criterion for determining what
makes a Bird of Prey cannot be a single
parameter like food alone.
SCIENCE REPORTER, JULY 2012
Hunters
in the
Sky
Birds of Prey are unique due to the diversity of their
feeding habits, as well as the unique mechanisms
endowed by Nature to accomplish their predatory act.
They have an important ecological niche as scavengers,
by consuming the carcasses of dead animals. There is an
urgent call to discourage the murder of these beautiful
gifts of nature.
Built for the Kill
Nature has endowed raptors with immense
power, strength and myriad mechanisms
that make them deadly hunters in the
avian world. Their hooked beaks are
designed to pierce the flesh of the victim
deeply and tear it into small pieces that
can be easily engulfed.
Among raptors, the toes of mammal
eaters are short and powerful and those
of birds or avian eaters are long and
slender. The feet and talons of predatory
birds are their preliminary tools for killing
and their beaks are for tearing. Moreover,
the talons have an automatic locking
system guarded by the plexus muscle to
ensure that the prey has no chance to
Large Raptors
The large raptors in the genus Harpies which includes Harpy Eagle and
Pithecophoga which includes Golden Eagle are considered as the largest
birds of prey among the raptors in the world. The Harpy Eagle of the genus
Harpia is a South American bird. The diet of the Harpy Eagle of the Amazon
basin includes monkeys, hornbills, small dogs, pigs and sometimes the
sedentary sloths.
From time immemorial, eagles with their graceful soaring and strength
are regarded as symbols of power. For example the Bald Eagle is the national
bird of USA. It is a fish eater like Osprey but if there is scarcity of food it also
feeds on dead and decaying carcasses.
Other types of Eagles like the Golden eagle of Europe are often called as
the “King of birds” because it hunts a wide spectrum of animals like rats,
rabbits, squirrels to small birds. The genus Aquila consists of true Eagles.
Aquilas have stronger feet. These include the Tawny Fish Eagle, Block
Eagle, Crested Serpent Eagle, Pallas Fish Eagle, etc. Kites also fall in the
family of large raptors. These include the common Pariah Kite and the water
loving Brahminy Kite. Both these Kites like proximity to human beings and
are seen scavenging in towns and villages.
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Peregrine falcon
escape from the deadly grip of raptors.
Some other species of raptors like the
Secretary bird of Africa have long legs and
feathered head crest. It feeds mainly on
reptiles like snakes, lizards etc. using their
feet to kill them. Their large sharp curved
claws known as talons help these birds in
piercing and throttling the victim.
Apart from these, the acute binocular
vision and auditor y acuity of these
masterful flyers make them able to stay
aloft for hours, scanning the entire area
and searching for prey with their keen eyes.
Whenever the raptors target any prey they
dive onto the chosen victim like a bullet.
The Peregrine falcons, which are
widely distributed worldwide, are attributed
as the fastest moving birds in the avian
world. The sky seems to be their
playground. They are the most
acrobatically designed of all the raptors
and are very well adapted for patrolling in
the open sky. They can charge any intruder
in their territory with a powered dive called
a stoop at a speed of almost 350 kmph.
Creasted serpent Eagle
Winged Scavengers
Surprisingly, the largest birds of prey are
not predators but carrion-feeders like
vultures and condors. Both have weak bills
and have vast wings with finger-like
projections and spend hours soaring high,
scanning across the landscape for
carcasses. The American condor is
unanimously considered as the largest
land bird with the greatest wing span. It
has a wing span of almost three metres
and weighs up to 14 kg.
Vultures are known as nature’s
scavengers
as
they
keep
the
environment clean by eating carcasses
and also maintain the ecological
balance. Asiatic vultures are currently
fighting for their survival. The present
declining trend of vultures across the
whole Indian subcontinent is a matter of
great concern. It calls for urgent
regulatory approach to monitor not only
their present scenario but also control
the factors that are driving vultures to the
verge of extinction.
The rate of disappearance of
vultures is so high that scientists
speculate that the three species of
vultures, i.e. Oriental White Rumped
vulture (Gyps bengalensis), Long Billed
vultures (Gyps indicus) and Slender
Billed vulture (Gyps tenuirostris) will be
extinct in less than ten years. According
to IUCN and Bird Life International,
these three species of vultures have
been categorized as “critically
endangered species”.
The Oriental white backed vulture was
once thought to be the common bird of
prey in the Indian skies. According to a
study conducted by the Bombay Natural
History Society (BNHS), about 98% of its
population has declined since 1992. The
numbers of long billed and slender billed
vultures have also fallen by the same
numbers in this period. The rapid rate of
decline of these species has made them
the fastest declining wild birds in near
history, with demise more rapid than that
of the dodo.
Oriental White Rumped Vulture Gyps bengalensisonce a common bird in our skies
(Source: http://en.wikipedia.org/wiki/Whiterumped_Vulture)
Long Billed Vulture Gyps indicus on a rock
(Source: http://en.wikipedia.org/wiki/Gyps_indicus )
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SCIENCE REPORTER, JULY 2012
Feature Article
Small Raptors
Kestrel
Hawks, Sparrow Hawks, Goshawks, Falcons, Kestrels and Harriers are
known as small raptors. They are comparatively smaller in size with their
large relatives and feed exclusively on other birds as well as grounddwelling animals. There are two main kinds of hawks: Accipiters and
Buteos. Accipiters such as Goshawks have short, rounded wings and a
narrow tail while Buteos such as the Kestrels and Buzzards have larger
wings and fan shaped tails. The Kestrel is often known as the “Wind
hover” because it hooves in mid-air keeping its head still and focusing on
the ground. On seeing its victim, it suddenly drops and pounces on its
prey and kills it.
Scientists proclaim that the real
mischief behind this phenomenon is
caused by veterinary drugs used on cattle,
which end up being consumed by vultures,
killing them. The most notorious of these is
the
anti-inflammator y
the
drug
Diclophenac, which was banned in 2006
as it kills vultures by causing acute renal
failure. Researchers have discovered that
yet another veterinar y drug named
Ketoprofen is fatal to the birds, particularly
vultures. In a laboratory trial by the BNHS
scientists, vultures which were fed on the
carcasses of livestock recently treated with
Ketoprofen died due to renal failure.
Ketoprofen also causes mortality by a
mechanism similar to Diclophenac; the
experimental birds suffered acute kidney
failure and died within a day of exposure.
Ketoprofen is sold under a variety of brand
names in the local markets. The
conservation
organization
Birdlife
International which sponsored the new
research along with the Bombay Natural
History Society (BNHS), is now attempting
for a tighter control and checking the use
of Ketoprofen in livestock throughout the
countr y
and
abroad.
Some
conservationists advocate greater use of
another drug known as Meloxicam which
is no longer under patent and is also not
fatal to the vultures.
The present fluctuation in the
population of vultures from the Indian soil
is now begetting a noticeable impact on
the environment such as piles of carcasses
and increasing risk of contamination of
water bodies. At this delicate moment it is
the call of the hour to save these
magnificent scavenger birds from
extinction.
Slender Billed Vultures Gyps tenuirostris (left)
(Source:http://www.birdlife.org/action/science/
species/asia_vulture_crisis/problem.html)
SCIENCE REPORTER, JULY 2012
48
There are about 295 known
species of raptors worldwide.
They hunt across a huge range
of habitats, from mountains to
rainforests.
A Plea for Conservation
Since time immemorial Birds of Prey are
the embodiment of power, endurance
and imaginable prosperity. But today these
birds are facing complete extinction due
to
human
belligerence
and
encroachments on nature. For birds of
prey, to kill is the most vital feature of their
lifestyle and this act maintains harmony
between the prey and predator in the
ecosystem. Like other large predators such
as sharks and tigers, birds of prey are
scarce to equilibrate the balance of
nature. Birds of prey have always been at
the top of the pyramid of numbers and
are fewer in number with respect to their
prey. Sadly, people try to kill these gentle
saviors of our environment just for trophies
and money, destroying its fine balance.
The human species seems to have
forgotten that they can rebuild the Taj
Mahal or Great Wall of China once again,
but they cannot recreate precious bird
and animal species which they have
ruthlessly driven to their death. So it is an
urgent need of the hour to save these
feathered friends before they disappear
from Planet Earth.
Mr Rahul Rohitashwa is Research Scholar and
Wild Life Activist, Mandar Nature Club, Bhagalpur
(Bihar). Address: S/o Dr. Vijay Vardhan, Laheri
Tola, Bhagalpur, Bihar-812002; Email:
[email protected]
Dr D.N. Choudhary is Assistant Professor,
Department of Zoology, P.N. College, Parsa,
J.P. Univ., Parsa, Saran (Bihar)-841219; Email:
[email protected]