Monday, October 3, 2016

Crimson Sunbird (Aethopyga siparaja)

Crimson Sunbird feeds largely on nectar,just in line with other sunbirds.About 11cm in size,one can see it hovering in the air around flowers.It perches to suck the nectar,but rarely stays for long at one place and continuously keeps on changing its position from one branch and flower to another. The long beak is typically made to suck the nectar from flowers,but at times  it consumes insects especially for feeding young ones and to meet the protein requirements during breeding season.


An Adult Male




























The adult male has a crimson/maroon coloured chest,sides and upper back.Lower back is olive green with a bluish green tail and head.The females have an olive green back and yellowish underparts.

Crimson Sunbird Female












Sub Adult (Photo Suneet Bhardwaj)














The subadults can be seen with various proportions of  crimson colour around throat, chest and upper back.









The bright colours of  body make it vulnerable to the attack of predators as it can be easily spotted, and therefore the quick movements are probably a defence to dodge them.I have often seen it arround maroon coloured or similar flowers which probably is a strategy to minimise the chances of being spotted by predators.



Thursday, August 4, 2016

Raptors,the ultimate Hunters


If we go by dictionary,the word Raptor means a bird of prey, e.g an eagle or hawk. Whenever we hear the word raptor the immediate phrase coming to our mind is "a bird of prey".The two terms are synonymously used for these birds which are commonly known as Raptors.The term Raptor has its origin in Latin verb Rapere and it literally means a plunderer,signifying that the raptors forcefully seize and carry away their prey.


Yellow Billed Blue Magpie
The foremost character of all the birds of prey is that they eat meat.But it does not distinguish them as a class,because there are many meat eating birds like Magpies(see photograph of Yellow billed Blue magpie carrying its prey in beak) and Crows.However these other meat eating birds do not use their  feet to kill and carry the prey and instead they depend on their beaks.The Raptors on the other hand make use of their strong legs and sharp talons to get hold of the prey and take it away.







Raptors have very strong hooked beaks,which they use to tear apart the meat.





















Above all they have got a very powerful eyesight to locate their prey even when they are in flight.Many times we see the vultures and kites soaring high in the sky.They have the capability to spot their prey from such great distances.

A Vulture looking for the prey


The basic characteristics of Raptors:-


They eat meat,the source of which can be a freshly hunted animal or the carcass of a dead one.


They  have got  powerful and sharp talons to grip,kill and carry the prey.

They have got  very strong curved beaks  for tearing the meat.


They have very powerful vision to spot their prey from a distance.








Nocturnal Birds of Prey



The Raptors are both Diurnal as well as nocturnal.The nocturnal birds of  prey i.e. Owls belong to the group Strigiformes which includes around 200 species of nocturnal birds with few diurnal exceptions.The Owls have a characteristic large broad head,binocular vision and powerful sense of hearing to locate the prey.They have sharp talons and their feathers are specially adapted for silent flight,giving them an opportunity to make use of their strong sense of  hearing.They hunt small mammals,birds and insects.

The Owls have a flexible neck which they can rotate to about 270 degrees.In the pictures below,compare the position of the head of the Asian Barred Owlet.The Owlet has managed to rotate its head by more than 270 degrees while sitting at one place.

Asian Barred Owlet














Asian Barred Owlet























The Diurnal Birds of Prey:


The Diurnal birds of prey are very different from their nocturnal counterparts.There may be around 300 species of diurnal raptors which are classified into five families:



The Accipitrids are the largest group of raptors,including Old World Vultures(found in Europe,Asia and Africa), Eagles, Hawks,Kites,Harriers, Buzzards and many others. 
A Vulture cutting through clouds in Himalayas


Cathartids are the New World Vultures living  in the continents of North and South America.They closely resemble the Storks or rather they are the short necked storks with hooked bills and bare heads. But due to their carrion eating habits,gliding flight and broad wings they have resemblance to true vultures as well.


An Osprey waiting for the right moment


Osprey is the only member of the family Pandionidae.
It’s diet consists of fish exclusively.It possesses unique physical characteristics and behaviour which helps it in hunting and catching fish.As a result of the unique characteristics,it has been given its own unique genus.



Just like Osprey, the Secretary bird is the only member in the family Sagittariidae. It is a large bird of prey endemic to Africa,usually found in open grasslands and Savannah of Sub-saharan Africa. They are known to kill snakes by stamping on them with their feet.



Falconids consisting of  Falcons and Caracaras have about  60 species of diurnal birds of prey.Falcons kill using their beaks unlike other raptors who use powerful feet to crush and kill the prey.For this purpose the Falcons have a well developed notch(Tomial tooth) on their beak which is used by them to break the neck of the prey.


Role of Raptors in Ecosystem:

Raptors are the top order predators at the apex of various food webs and food chains.At the highest level of hierarchy they keep a check on the populations of insects,rodents and snakes.Some of the larger birds of prey feed on the carcasses of dead animals.Many times they  hunt weak or diseased animals and prevent the spread of disease carrying bacteria and germs.

They have wide home range areas,and they are sensitive to human disturbance and environmental changes.Being at the apex of food webs/chains they are an indicator of ecological health.Habitat loss,Pesticides,Chemicals and other factors have the most dramatic impact on top predators,so these birds of prey can be easily referred to be the indicators of  Environmental health.