Factual Description:-
Common Name:- Indian Roller
Scientific Name:- Coracias benghalensis
Description
The Indian Roller (Coracias benghalensis), is a member of the roller family of birds. It belongs to the Coraciidae family of birds. They are found widely across tropical Asia stretching from Iraq eastward across the Indian Subcontinent to Indochina and are best know for the aerobatic displays of the male during the breeding season. It is also called as the "Blue Jay" in former times is a member of the roller family of birds. The largest populations of the species are within India, and several states in India have chosen it as their state bird. It is not migratory but undertakes some seasonal movements. They are very commonly seen perched along roadside trees and wires and are commonly seen in open grassland and scrub forest habitats. The IUCN status of the bird is "Least Concern". The Indian Roller gains its name from its elaborate courtship displays, during which it performs some starting aerobatics culminating in a series of 'rolling' motions.
Shape & Size
The Indian Roller is a stocky bird about 26-27 cm long and can only be confused within its range with the migratory European Roller. It weights around 90 gm and has a wingspan of 65-74 cm. The Indian Roller is a medium-sized bird which, when perched, appears a fairy drab brown, with a blue crown and lower wing. In flight, however, it is extremely striking, with its deep purple-black wings, bright blue rump, and a blue band across the tail becoming visible. Its eyes are greyish-brown and the strong, hook-tipped bill is a blackish-brown. The nostril is long and exposed and there are long rictal bristles at the base of the bill. Male and female are similar in appearance.
Habitat
The Indian Roller is distributed across Asia, from West Asia (Iraq), through Indian Subcontinent (including Sri Lanka and the islands of Lakshadweep and Maldive islands) into Southeast Asia.
The main habitat is usually areas of thin deciduous forests and grasslands. This bird also dwells in wide open cultivated areas. However, the bird is often spotted in parks and on electric wires of urban cities.
Diet
Indian Roller is omnivorous. It mainly feeds on frogs. It also favours lizards, acorns, grasshoppers, crickets, butterflies and moths. Fires attract them and they will also follow tractors for disturbed invertebrates. They are often attracted to road kills. Nearly 50% of their prey was beetles and 25% made up by Grasshoppers and crickets. When hunting, the Indian roller typically sits motionless at a high vantage point, from which it can scan the ground for potential prey items. When prey is spotted, it will drop down to snatch it and then return immediately to its perch to consume it. On other occasions the Indian roller feeds directly from the ground, and moves around an area foraging for potential insect prey.
Breeding
The breeding season of the Indian Roller begins in the early summers just after spring. The starting courtship displays by the males become evident right from the month of February itself. During this interesting display the male flies high up in the sky and returns back down towards the earth in a rotating motion, while flapping its wings rapidly and producing harsh sounds. April is the month of bird lays eggs in tree holes or similar places. It lays 4-5 eggs. The incubation period for the eggs last for a maximum of 20 days. The eggs are incubated by both male and female. The young birds begin to acquire their flight feathers after approximately 35 days. Although groups of Indian rollers are rarely seen, family groups may form, and communicate with a series of loud 'chack' calls, which become harsher and more regular during times of threat.
Ecology and behaviour
The bird usually seen perched on prominent bare trees or wires. They descend to the ground to capture their prey which may include insects, arachnids, small reptiles and small snakes and amphibians. They perch mainly on 3-10 metre high perches and feed mostly on ground insects. Nearly 50% of their prey are beetles and 25% made up by grasshoppers and crickets. The feeding behaviour of the roller and habitat usage are very similar to that of the Black Drongo. During summer, they may also feed late in the evening and make use of the artificial lights and feed on insects attracted to them. They are attracted to swarms of winged termites and as many as 40 birds have been seen perch on a 70 metre stretch of electric wires. Their habit of feeding near roadsides sometimes results in collisions with traffic. The display of this bird is an aerobatic display, with the twists and turns that give this species its English name. The breeding season is March to June, slighty earlier in southern India. Displays when perched include bill-up displays, bowing, allopreening, wing drooping and tail fanning. Holes created by woodpeckers or wood boring insects in palms are favaoured for nesting in some areas. Nest cavities may also be made by tearing open rotten tree trunks or in cavities in building. The cavity is usually unlined and is made up mainly to 19 days. The young fledge and leave the nest after about a month. Nearly 80% of the eggs hatch and feldge.
The bird bathes in open water by plunge-diving into it, a behaviour often interpreted as fishing. But it may occasionally attempt fishing from water.
Blood parasites Leucocytozoon of the family Plasmodiidae have been noted in the lung tissues. Parasitic helminth worms Hadjelia truncata and Syanhimantus spiralis were recorded as well.
Call
The call of the Indian Roller is a harsh crow-like 'chack' sound. It also makes a variety of other sounds including metallic 'boink' calls. It is especially vociferous during the breeding season.
Sub-species
There are two sub-species of Indian Roller, namely- European Roller (Coracias garrulus) amd Dollarbird (Eurystomus orientalis).
In culture
Being very common in the populated plains of India, it is associated with legends. A local name is "Neelkanth" (meaning blue throat), a name associated with the deity Shiva (who drank poison resulting in the blue throat). During former times, a captive roller would be released by the local ruler during festivals such as Dussera and Durga Puja. Adding its chopped feathers to grass and feeding them them to cows was believed to increase their milk yield.
Interesting fact
Being such a charismatic species, Indian Roller has been chosen as the State bird by the Indian States of Andhra Pradesh, Karnataka and Odisha.
Lifespan
The longevity of Indian Roller exceeds up to 17 years of age.
References:
1. http://www.animalspot.net/indian-roller.html
2. http://beautyofbirds.com/indianrollers.html
3. http://www.arkive.org/indian-roller/coracias-benghalensis/
4. http://apbiodiversity.ap.nic.in/Indian%20Roller.html
5. http://www.ecoindia.com/animals/birds/indian-roller.html
6. http://en.wikipedia.org/wiki/Indian_Roller
7.
