01 October 2008

The Crow

Both the House Crow and Jungle Crow are to be found throughout Tiruvannamalai District. As I was sitting in my garden this afternoon I noticed both varieties feeding and generally taking over the area. Since I moved into this house nearly three years ago, I have regularly put food out for birds and animals but it was only about six months ago that the crows started to visit -- which was a pity because as I mention in the below posting both the House and Jungle Crows are great bullies to small ornamental birds.

I became so irritated with the 'Caw Caws,' as I nickname them, that I spoke with several farmers and villagers and also did some serious 'Goggling,' to find out how to deter both kinds of Crows visiting my garden. Well I found the most popular and supposedly 'fool proof' method practised in both India and the West is to kill a crow and hang it in a prominent spot -- meant to work like a charm -- but thought it a little too gruesome so went on to Plan B.

Plan B a local farmer assured me, was equally foolproof and that was to tie black rags in my trees at prominent spots. Well the day after this was done, I sat and waited to see what my regular Crow visitors would do. If ever a bird could look 'startled' -- that is exactly how I would describe the reaction of the visiting Crows. Well the black rags worked for about a day and a half and then the rags lost their dramatic impact, and the Crows happily returned in number.

Next I tried Plan C which was to tie shiny CD-Roms onto tree limbs and let them waive around in the wind. And the Crows actually didn't seem to like that especially on a sunny day (i.e. most days at Tiruvannamalai) when the revolving CDs shimmer and dazzle in the sunlight. Part two of Plan C (which I have yet to do) is to put wind chimes in the trees -- as this supposedly is meant to irritate Crows. We shall see!

In the meantime hope you enjoy the information and photographs I have gathered explaining the difference between two of the most numerous birds in Tiruvannamalai District i.e. the House Crow and the Jungle Crow.

House Crow

The House Crow (Corvus splendens) is a widespread resident of Tiruvannamalai District and can be found all over India except in high altitudes and forests. Its size is about that of a pigeon; around 42 cms with weight ranging between 250-350 gm. The bird has a glossy black plumage, except for its grey collar. Its bill, legs, and feet are black.

There are four geographical races of the House Crow which are based largely on paleness or darkness of the collar. Sexes alike. Its normal call is a harsh The voice is a harsh ‘caaa-caaa’ or a nasal ‘kaan kann’. It reserves its softer calls for resting and during courtship! Its name in Tamil is: Nalla Kaka, Maniyan Kakai

The bird is vocal, gregarious and seemingly unafraid of people. Audacious, cunning and uncannily wary. It is aggressive and will attack and chase off large birds of prey. Breeding pairs will repeatedly dive bomb humans near their nest. This species is able to make use of resources with great flexibility and appears to be associated with humans.

It is perhaps the most familiar bird of Indian towns and villages. It is a highly opportunistic bird and given its omnivorous diet, it can survive on nearly anything that is edible. It feeds largely on human scraps, small reptiles and other animals such as insects and other small invertebrates, eggs, nestlings, grain and fruits. Most food is taken from the ground, but also from trees as opportunity arises.

The House Crow is a useful scavenger but also a great bully and therefore a serious menace to defenseless ornamental bird species in urban areas. It enjoys community roosts in selected trees or groves where large numbers collect very night but is a solitary nester except in areas of high population density.

Its nest is generally a platform of twigs frequently intermixed with iron wire, with cuplike depression lined with tow, coir fibres. And in high density areas, sometimes there are several nests in the same tree. The House Crow will use trees, buildings, or other artificial structures for its rough stick nest lined with coir or other fibre. It lays 4-5 pale blue-green eggs, speckled with brown. Breeding season March through July. Its nest is regularly brood-parasitized by Asian Koel.


Jungle Crow

The Jungle Crow (Corvus macrorhynchos), or Indian Corby, is a widespread Asian species of Crow. It is highly adaptable and able to survive on a wide range of food sources. This bird has a large bill and due to this it is sometimes called Large-billed Crow or Thick-billed Crow. There are three sub-species within this group with one of them i.e. with Corvus (m.) Culminatus ‘Indian Jungle Crow’ being found in Tiruvannamalai District and other parts of India.

The bird is glossy jet black with a heavy bill and deep and horse ‘caw’. Sexes alike. Singly, pairs or loose parties. It is larger than the House Crow and is found throughout the Indian Union. Local Tamil names for it are Kaka and Kakam.

It is generally found in the countryside, but small numbers are also in towns and villages. The Jungle Crow associates with vultures to feed on carrion and its movements often lead to discovery of large cat kills hidden in the jungle which the bird is quick to locate. The bird is omnivorous, and highly destructive to eggs and chicks of other birds including domestic poultry and young of small mammals.

It has a long bill with the upper one thick and arched, making it look heavy and almost Raven-like. Generally, all forms have dark greyish plumage from the back of the head, neck, shoulders and lower body. Their wings, tail, face and throat are glossy black and the depth of grey shading is almost black. It will take food from the ground or in trees and attempts to eat anything, alive or dead, plant or animal. It is also one of the most persistent species. It is quite bold, especially in urban areas.

The nest is a platform of twigs, usually high up on a tree. There are normally 3-5 eggs. The egg is a broad oval, pointed at the smaller end. The colour is any shade of blue-green, blotched and speckled. In Peninsular India the Jungle Crow breeds from December to April. The nest is built in a fork of a tree, and is a shallow cup of sticks, sometimes neat and well made, sometimes sketchy and ragged; it is lined with grass roots, wool, rags, vegetable fibre, and similar materials. Some nests have been found to be built partly or exclusively of wire. Both sexes share parental duties. Nests frequently parasitized by Koel.

Gregarious at roosts with many thousands at some sites. Large flocks may be seen at dusk arriving at major roosts. The birds’ voice is deeper and more resonant than the House Crow with its usual sound being "caaa-caaa-caaa".

No comments: