Red-vented Bulbul

Factual Description:-

Common Name:- Red-vented Bulbul

Scientific Name:- Pycnonotus cafer

Other local names: - Hindi- Kala bulbul, Bulbuli, Guldum, Himachal Pradesh-Kala painju, Assamese- Bulbuli sorai, Cachar- Dao bulip, Dafila- Nili betom, Lepcha- Mancleph-pho, Naga- Inrui bulip, Bhutan- Paklom, Bhil- Peetrolyo, Gujrati- Hadiyo bulbul, Kutchi- Bhilbhil, Marathi- Lalbudya bublbul, Oriya- Bulubul, Tamil- Kondanchiradi, Konda- Lati, Kondai kuruvi, Telugu- Pigil-pitta, Malayalam- Nattu bulbul, Kannada- Kempu dwarada pikalara, Sinhalese- Konde kurulla.

Description

The Red-vented Bulbul is a member of the bulbul family of passerines. It is resident breeder across the Indian Subcontinent, including Sri Lanka extending east to Burma and parts of Tibet. It has been introduced in many other parts of the world and has established itself in the wild on several pacific islands including Fiji, Samoa, Tonga, and Hawaii. It has also established itself in parts of Dubai, the United Arab Emirates and New Zealand. It is included in the list of world's 100 worst invasive alien species. 

The aggressive nature and fruit-eating habits of the red-vented bulbul have unfortunately resulted in it being considered one of the world's worst invasive alien species in areas where it has been introduced. The sexes are similar in plumage, but young birds are duller than adults. The typical call has been transcribed as ginger beer but a member of sharp single note calls likened as pick are also produced. Their alarm calls are usually responded to and heeded by many other species of bird. Melanistic and leucistic individuals have been noted. 

Taxonomy

The Red-vented Bulbul was originally decscribed by Linnaeus in 1766. Several populations of this widespread species have been named as subspecies (or races). The nominate race is found in southern India. The type locality of Puducherry was designated by Erwin Stresemann. The race in the western part is intermedius and is found in Kashmir and Kohat down to the Salt Range and along the Himalayas to Kumanon. The race bengalensis is found in the Himalayas from Nepal east to Assam. South of these tow forms are pallidus to the west south to Ahmednagar and saturatus along the east, south to the Godavari. There are no distinct boundaries to these racial forms and recent works do not recognize saturatus (designated by Whistler & Kinnear, 1932 for the northeastern Peninsular India) but accept the desert form humayuni (earlier named as pallidus) from Sindh and northwest India, northeast Indian stanfordii (= stanfordi Deignan, 1949) amd the Sri Lankan race haemorrhous (= haemorrhousus (J.F. Gmelin, 1789)). Race melanchimus is found in Southern Burma and northern Thailand. Race chrysorrihoides is found in China. Two formerly designated races nigropileus in Southern Burma and Burmanicus of Northern Burma are considered as hybirds. 

Shape, Size & Morphology

The upperparts and breast of the red-vented bulbul are dark sooty brown, although each brown feather has a pale edge, resulting in a 'scaly' appearance. The brown breast shades to a white belly and a white, occasionally cinnamon, rump, and the tail is brown with white tips. The brownish is plumage of the body contrast with the glossy black head, which bears a tufted crest of feathers at top of crown. Underneath the tail, around the vent, is the patch of vivid scarlet feathers for which this bird is named. 

Size of the bird is around 20 cms or 8.5 inches in length. 

Habitat

Red-vented Bulbul is a bird of dry scrub, open forest, plains and cultivation lands. In its native range it is rarely found in mature forests. A study based on 54 localities in India concluded that vegetation is the single most important factor that determines the distribution of the species. 

Distribution

It has been introduced into Hawaii, Fiji and New Zealand. The were introduced to Samoa in 1943 and became common on Upolu by 1957. Red-vented Bulbuls were introduced to Fiji around 1903 by indentured labourers from India. They established on the Tongan islands of Tongatapu and Niuafo'ou. They were seen i Melbourne around 1917 but not seen after 1942. They established in Auckland in the 1950's but were exterminated. They prefer the dry lowland regions in these introduced regions. They are considered as pests because of their habit of damaging fruit crops. They can also disperse the seeds of invasive plants like Lantana camara and Miconia calvescens. 

Diet

Found foraging in both pairs and large flocks, the red-vented bulbul eats mostly soft fruits (such as bananas), berries, seeds and nectar. It is also not uncommon to find this species feasting on insects, and even small reptiles, such as geckos. The red-vented bulbul tends to swallow fruits whole and thus the seeds travel through its digestive systems completely intact, making the red-vented bulbul particularly important for dispersing plant seeds. 

Breeding 

The red-vented bulbul may breed year-round, although breeding activity peaks between January and October. It is thought to have up to three broods within a year, with each brood typically containing two to four eggs. The nest, which is built in just a couple of days, is a shallow cup made from twigs, roots, and other materials such as metal wire and cobwebs. The distinctive eggs of the red-vented bulbul, which are pale pink with darker reddish or purple patches at the broader end, are incubated for about 14 days. 

Behaviour and Ecology 

Their vocalizations are usually stereoped and they call throughout the year. However a number of distinct call types have been  identified incuding roosting, begging, greeting, fight and the two kinds of alarm calls. They are important dispersers of seed of plants such as Carissa spinarum.  The red-vented bulbul was among the first animals other than humans that was found to be incapable of synthesizing vitamin C. However, a large number of birds were later found to likewise lack the ability to synthesize Vitamin C. Like most birds, these bulbuls are hosts to coccidian blood parasites while some bird lice such as Menacanthus guldum have been described as ectoparasites. 

In Culture

In 19th century India, these birds were frequently kept a cage pets and for fighting especially in the Carnatic region. The would be held on the finger with a thread attached and when they fought they would seize the red feathers of the opponents. 

IUCN Status

The red-vented bulbul is classified as Least Concern (LC) on the IUCN Red List. 

References:-

1. http://www.arkive.org/red-vented-bulbul/pycnonotus-cafer/

2. http://en.wikipedia.org/wiki/Red-vented_bulbul

3. http://identify.whatbird.com/obj/1144/overview/Red-vented_Bulbul.aspx

4. http://www.birdlife.org/datazone/speciesfactsheet.php?id=7196

5. http://www.wild-facts.com/2012/wild-fact-393-a-piercing-sound-bulbul/

6. http://thewebsiteofeverything.com/animals/birds/Passeriformes/Pycnonotidae/Pycnonotus-cafer

7. http://beautyofbirds.com/redventedbulbuls.html

8. http://www.bird-friends.com/BirdPage.php?name=Red-Vented+BulBul

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Red Avadavat or Red Munia

Factual Description

Common Name:- Red Avadavat or Red Munia

Scientific Name:-  Amandava amandava

Other common names:- Waxbill, Tiger Finch, Amaduvade, Strawberry Finch, Avadavat. 

Description

The Red Avadavat, Red Munia or Strawberry Finch (Amandava amandava) is a sparrow-sized bird of the Estriididae family. It is found in the open fields and grasslands of tropical Asia and is popular as a cage bird due to the colourful plumage of the males in their breeding season. It breeds in the Indian Subcontinent in the Monsoon season. The species name of amandava and the common name of avadavat are derived from the city of Ahmedabad in Gujarat from where these birds were exported into the pet trade in former times. Both sexes have random white spots throughout there plumage, bright red beaks, flesh coloured legs and the eyes are black enriched by red-brown. This small finch is easily identified by the rounded black tail and the bill that is seasonally red. The rump is red and the breeding male is red on most of the upper parts except for a black eye-stripe, lower belly and wings. There are white spots on the red body and wing feathers. The non-breeding male is duller but has the red-rump while the female is duller with less of the white spotting on the feathers.

Distribution

Their natural range stretches from the Indus valley of Pakistan to the plains of the Brahmaputra extending south to the peninsula of India. The species has four named populations. The nominate subspecies is found in Bangladesh, India, Sri Lanka, Nepal and Pakistan; the Burmese form has been called flavidiventris (also found in parts of China, Indonesia, Thailand and Vietnam); the population further east in java is called punicea and in Cambodia decouxi.

Evolution and systematics 

The Red Avadavat were earlier included in the genus Estriida by Jean Delacour. This placement was followed for a while but morphological, behavioural, biochemical and DNA studies now support their separation in the genus Amandava. The Estriidinae are thought to have evolved somewhere in the Indian plate and moving into the African and Pacific regions and it has been estimated that the Red Munia diverged from the Green Munia about nine million years ago. 

Shape, Size & Morphology

Red Avadavats are about 10.16 cms in length (3-4 inches). Average wingspan is around 49mm. Males and females molt into breeding plumage each year. Duing the breeding season males have a deep red crown and back, and there are white streaks under the eyes. The sides of the head, down the breast and the undersides are scarlet. The wings, tail overfeathers, and flanks are dark red with white spots. The tail feathers are black. The beaks of the males are red. When females go into the breeding season they often molt and the chest and underbelly become a brighter yellow-orange. 

At the end of the breeding season, males begin to molt to a plumage that resembles the coloration of females. The color of the underbelly ranges from a creamy tan to creamy yellow, and there are black streaks under the eyes. The crown, back, wings and tail are dark brown with fewer white spots than male in breeding season. Juveniles of this species are dull grayish brown all over. This is the first molt from the nesting stage. Nestlings are marked by dark skin and down, and have markings around the mouth. 

Habitat

Red avadavats are found in grassy areas, such as jungle clearings, gardens, and meadows. They also frequent sugarcane fields and areas near bodies of water, such as marshes. Red avadavats are accustomed to tropical temperatures and will lose plumage intensity in cooler, dryer environments. Habitat regions: tropical; terrestrial.

Diet

Red avadavats feed on a variety of food sources. They are known mainly as ground feeders. But these are omnivorous , feeds on insects too. When feeding young, they prefer and larvae and pupae, centipedes and caterpillars. Plant diet includes seeds, grains, and nuts.

Breeding

Red avadavats breed once a year. Breeding can occur from january to April, varying regionally. Lays 4 to 6 eggs per season. Average time to hatching is 11 days. Average fledging age is 20 days. 

Male red avadavats use their bright red plumage in addition to a mating dance to attract females. The dance begins with males, a grass stem or feather in their mouth, deeply bowing with feathers erect. Usually the birds sing and hop between bows. Both males and females display. When the birds have paired, they separate from the larger group to built a nest. Red avadavats are monogamous within a breeding season, but no information could be found on potential life long monogamy. 

Breeding months vary regionally. Males begin molting into their bright plumage as the breeding season begins. Out of the breeding season, males often do not entirely lose their red plumage before beginning molting for the breeding season. In the wild (in parts of Asia), red avadavats breed during the second half of the monsoon season and during the following dry season. 

Assam: June-August

Northern India: July-October

Southern India: October-March

Myanmar (Burma): August-January

Flores: April-June

Behaviour and Ecology

Red avadavats are gregarious in nature, usually in small flcoks, flying with rapid wingbeats and descending into grass clumps where they are hard to observe. Pairs stay together during the breeding season. These birds produce a distinctive low single note pseep call that is often given in flight. The song is a series of low notes. Birds of a flock will preen each other, ruffing their head feathers in invitation. They feed mainly on grass seeds but will also take insects such as termites when they are available. They built a gobular nest made of grass blades. The usual clutch is about 5 or 6 white eggs. The beak begins to turn red in May and darkens during November and December. The beak then turns rapidly to black in April and the cycle continues. These seasonal cycles are linked to seasonal changes in daylength. 

Call

Makes "pseep" calls oftenly during the flight.

Ecosystem roles

Because red avadavats feed on seeds and small insects, they likely have a role in seed dispersal as well as pest control. They are also prey for larger predators. There is little additional information on the roles red avadavats have on the ecosystem. Ecosystem impact: disperse seeds. 

Predation 

To protect against predation, red avadavats stay in large groups, especially during the non-breeding season. Also, when they are alarmed, they move their tails from side to side and at a down angle. During the non-breeding season, brightly coloured males lose their plumage and become brown, much like the females. This brown plumage may serve as camouflage during the dry season. Both breeding and non-breeding birds use a shrill call if they perceive danger, warning other group members. There is little information on predators of red avadavats.

References:-

1.  http://eol.org/pages/1053068/details

2. http://www.birdlife.org/datazone/speciesfactsheet.php?id=8663

3. http://www.finchinfo.com/birds/finches/species/red_avadavat.php

4. http://beautyofbirds.com/strawberryfinches.html

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