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Thursday, November 22, 2007

Green Heron, Everglades National Park, Florida

The Green Heron (Butorides virescens) is a small heron. Some sources consider this bird and the Striated Heron or Mangrove Heron, Butorides striatus, of tropical Africa and Asia, to be a single species, the Green-backed Heron.

Description
The green heron is relatively small; adult body length is about 44 cm. The neck is often pulled in tight against the body. Adults have a glossy, greenish-black cap, a greenish back and wings that are grey-black grading into green or blue, a chestnut neck with a white line down the front, grey underparts and short yellow legs. The bill is dark with a long, sharp point. Female adults tend to be smaller than males, and have duller and lighter plumage, particularly in the breeding season. Juveniles are duller, with the head sides, neck and underparts streaked brown and white, tan-splotched back, and greenish-yellow legs.

Habitat
Their breeding habitat is small wetlands in eastern and midwest North America, Central America, the West Indies and the Pacific coast of Canada and the United States. They nest in a platform of sticks often in shrubs or trees, sometimes on the ground, often near water. The female lays 3 to 5 eggs. Both parents incubate for about 20 days until hatching, and feed the young birds which take a further 3 weeks to fledge.

Northern Green Heron populations of the race B. v. virescens are migratory and winter from the southern United States through to northern South America. This subspecies is an extremely rare vagrant to western Europe.

Behavior
Green Herons stand very still on shore or in shallow water and await prey. They mainly eat small fish, frogs and aquatic insects. They sometimes drop food, insects, or other small objects on the water's surface to attract fish, making them one of the few known tool-using species. Feeding is done during the day. Their call is a loud and sudden kyow.

Green herons are seasonally monogamous. Nests are constructed in forest and swamp patches, over water or in plants near water. Locations in trees are preferred, with nests built up to 20 m off the ground. The clutch is 2 to 4 eggs, which are laid in 2-day intervals. The chicks are fed by both parents, though the frequency of feedings decreases as they become more independent. When chicks are 16 to 17 days old, fledging occurs, and they become independent after 30 to 35 days.

Scarlet Ibises, Venezuela

Eudocimus ruber) is a species of ibis that occurs in tropical South America and also Trinidad and Tobago. It is the national bird of Trinidad and is featured on the Trinidad and Tobago coat of arms along with Tobago's national bird Rufous-vented Chachalaca.

Adults are 56-61 cm long and weigh 650g. They are completely scarlet, except for black wing-tips. They nest in trees, laying two to four eggs. Their diet includes crustaceans and similar small marine animals. A juvenile Scarlet Ibis is grey/white in colour; as it grows the ingestion of red crabs in the tropical swamps gradually produces the characteristic scarlet plumage.

This species is very closely related to the American White Ibis and is sometimes considered conspecific with it.

While the species may have occurred as a natural vagrant in southern Florida in the late 1800s, all recent reports of the species in North America have been of introduced or escaped birds. Eggs from Trinidad were placed in White Ibis nests in Hialeah Park in 1962, and the resulting population hybridised with the native ibis, producing "pink ibis" that are still occasionally seen.

Blue Footed Booby, Galapagos Islands

The Blue-footed Booby (Sula nebouxii) is a bird in the Sulidae family which comprises ten species of long-winged seabirds. The blue-footed booby is medium to large in size. It is on average 81 cm long and weighs 1.5 kg (3 lb), with the females slightly larger than the males. It has long pointed wings and a wedge shaped tail. They have strong thick necks. The boobies eyes are placed on either side of their bill and oriented towards the front. They have excellent binocular vision. The blue-footed boobies eyes are yellow. The male has more yellow on its iris than does the female. The blue-footed booby has permanently closed nostrils specialized for diving. They breath through the corners of their mouths. Their feet range from a pale turquoise to a deep aquamarine. Males and younger birds have lighter feet than females do.

The name “booby” comes from the Spanish term bobo, which means "stupid fellow". This is because the Blue-footed Booby is clumsy on the land, and like other seabirds can be very tame. It has been known to land on boats, where it was once captured and eaten.

The natural breeding habitat of the Blue-footed Booby is tropical and subtropical islands off the Pacific coast of South America from Peru to Mexico including, most famously, the Galápagos Islands.

Wednesday, November 21, 2007

Indian Peafowl, Children's Zoo, Saitama, Japan

The term peafowl can refer to the two species of bird in the genus Pavo of the pheasant family, Phasianidae. The African Congo Peafowl is placed in its own genus Afropavo and is not dealt with here. Peafowl are best known for the male's extravagant tail, which it displays as part of courtship. The male is called a peacock, the female a peahen, though it is common to hear the female also referred to as a "peacock" or "female peacock". The female peafowl is brown or toned grey and brown.

The Indian Peafowl is a resident breeder in the Indian subcontinent. The peacock is designated as the national bird of India.

The Green Peafowl breeds from Myanmar east to Java. The IUCN lists the Green Peafowl as vulnerable to extinction due to hunting and a reduction in extent and quality of habitat.

The Indian Peafowl is monotypic, while the Green Peafowl has 3 subspecies, P. muticus spicifer, P. m imperator and the nominate P. m. muticus.

The two species are largely allopatric but will hybridise in captivity.

While the form of Green Peafowl in Yunnan is not separated taxonomically, it differs in a few aspects from other forms, particularly in its forest-dwelling habits, an "odd, monal-like bill", a curiously long hind toe and longer, more slender wings (K. B. Woods in litt. 2000). Some have suggested this is a new subspecies.

Some pheasant breeders have suggested that the Green Peafowl may have more subspecies.

Peafowl have sometimes been included in a distinct family from Pheasants.

The male (peacock) Indian Peafowl has iridescent blue-green or green coloured plumage. The so-called "tail" of the peacock, also termed the "train", is not the tail quill feathers but highly elongated upper tail coverts. The train feathers have a series of eyes that are best seen when the tail is fanned. Both species have a head crest.

The female (peahen) Indian Peafowl has a mixture of dull green, brown, and grey in her plumage. She lacks the long upper tail coverts of the male but has a crest. Females can also display their plumage to ward off danger to their young or other female competition.

The Green Peafowl is very different in appearance to the Indian Peafowl. The male has green and gold plumage and has an erect crest. The wings are black with a sheen of blue.

Unlike the Indian Peafowl, the Green Peahen is very similar to the male, only having shorter upper tail coverts and less iridesence. It is very hard to tell a juvenile male from an adult female.

Many of the brilliant colours of the peacock plumage are due to an optical interference phenomenon (Bragg reflection) based on (nearly) periodic nanostructures found in the barbules (fiber-like components) of the feathers.

Different colours correspond to different length scales of the periodic structures. For brown feathers, a mixture of red and blue is required: one color is created by the periodic structure, and the other is a created by a Fabry-Perot interference peak from reflections off the outermost and innermost boundaries of the periodic structure.

Such interference-based structural color is especially important in producing the peacock's iridescent hues (which shimmer and change with viewing angle), since interference effects depend upon the angle of light, unlike chemical pigments.

The peafowl are forest birds that nest on the ground. The Pavo peafowl are terrestrial feeders but roost in trees.

Both species of Peafowl are believed to be polygamous. However, it has been suggested that "females" entering a male Green Peafowl's territory are really his own juvenile or subadult young (K. B. Woods in litt. 2000) and that Green Peafowl are really monogamous in the wild. Those who subscribe to this notion cite the similarities between the sexes.

During mating season they will often emit a very loud high pitched cry.

Peafowl are omnivorous and eat plant parts, flower petals, seed heads, insects and other arthropods, reptiles, and amphibians.

In common with other members of the Galliformes, males possess metatarsal spurs or "thorns" used primarily during intraspecific fights.

Asiatic peafowl like the Indian Blue Peafowl and especially the Green Peafowl occupy a similar niche as the roadrunners, secretary bird, and seriema. All of these birds hunt for small animals including arthropods on the ground and tall grass and minnows in shallow streams.

Because of human encroachment into their natural territories, peafowl and humans have come into increasing contact. Because of their natural beauty some are reluctant to classify the birds as pests, but their presence can be disturbing.

Mealy Parrot, Amazon Rainforest, Peru

The Mealy Amazon or Mealy Parrot (Amazona farinosa) is one of the largest Amazon parrot species.

The Mealy Parrot occurs in tropical Central America and South America. It frequents humid to semi-humid forest (only rarely in deciduous forest) and plantations. In regions dominated by open/dry habitats it is restricted to gallery forest or completely absent.

It has a total length of 38-40 cm (14.96-15.75 in) and weighs 540-700 g (19.01-24.64 oz). Captives commonly are heavier. It is among the largest parrots in the Americas, mainly being surpassed by a the large macaws. As the other members of its genus, the Mealy Parrot has a relatively short, squarish tail.

The Mealy Parrot is mainly green. The back and nape often have a whitish tinge; almost as if it had been covered in a thin layer of flour ("meal"; hence its name). The distal half of the tail is paler and more yellow than the basal half, thus resulting in a distinctly bi-coloured look. In flight it shows a bluish-black trailing edge to the wing and a conspicious red speculum. Occasionally a few yellow feathers are apparent on the top of the head and two subspecies, virenticeps and guatemalae, have a bluish-tinged crown. The maroon to orange eyes (typically appear dark from a distance) are surrounded by a relatively broad white eye-ring of bare skin.

The Mealy Parrot is social and can be found in pairs or in large flocks. They are even known to interact with other parrots, such as macaws. They are usually quiet but can be loud at dusk and dawn. In captivity, they are know as one of the gentlest and calmest of all amazons.

When Mealy Parrots reach sexual maturity they usually form monogamous relationships with a single partner.

Courtship usually begins in early spring. The hen will usually lay three eggs, which she incubates for 28 days. The male will eat for both himself and the female during the incubation period. He will regurgitate the food for the female and chicks to eat.

The diet of the Mealy Parrot consists mostly of fruits, seeds, berries, nuts, blossoms, and leaf buds.

Kell-Billed Toucan, Barro Colorado Island, Panama

Toucans are near passerine birds from the neotropics. They are brightly marked and have large, colorful bills. The family includes five genera and about forty different species.

Toucans range in size from the Lettered Aracari (Pteroglossus inscriptus), at 130 g (4.6 oz) and 29 cm (11.5 inches), to the Toco Toucan (Ramphastos toco), at 680 g (1.5 lb) and 63 cm (25 inches). Their bodies are short (of comparable size to a crow's) and thick. The tail is rounded, and varies in length from half the length to the whole length of the body. The neck is short and thick, and at the base of the head is a huge, brightly-colored beak that measures, in some large species, more than half the length of the body. A toucan's tongue is long, narrow, grey, and singularly frayed on each side, adding to its sensitivity as an organ of taste.

The legs of a toucan are strong and rather short. Their toes are arranged in pairs with the first and fourth toes turned backward. Males and females are the same color. The feathers in the genus containing the largest toucans are generally black, with touches of white, yellow, and scarlet. The underparts of the ara├žaris (smaller toucans) are yellow, crossed by one or more black or red bands, and the edges of the beak are saw-toothed. The toucanets have mostly green plumage with blue markings.

Toucans are frugivorous (fruit-eating), but will take prey such as insects and small lizards. However, the function of the beak in feeding is not known, since many other birds consume these foods without the giant bill to help them. One likely use is to specialize on prey such as nestlings and bats in treeholes. In this view, the beak allows the bird to reach deep into the treehole to access food unavailable to other birds.

They are arboreal and nest in tree holes laying 2–4 white eggs. The young hatch completely naked, without any down. Toucans are resident breeders and do not migrate. Toucans are usually found in pairs or small flocks.

The name of this bird group is derived from Tupi tucana, via French.

Tuesday, November 20, 2007

Dark-Eyed Junco


Junco hyemalis), is the best-known species of junco, a genus of small American sparrows.

Adults are generally grey on top with a white belly. The white outer tail feathers flash distinctively in flight. The bill is usually pinkish. The males tend to have darker, more conspicuous markings than the female. Juveniles often have pale streaks and may even be mistaken for a Vesper Sparrow until they acquire adult plumage at 2 to 3 months. There are several regional variations:

The Slate-colored Junco (J. hyemalis hyemalis) has a dark slate-grey head, breast and upper parts. Females are brownish grey. It is found in North America in taiga forests from Alaska to Newfoundland and south to the Appalachian Mountains, wintering further south; it is relatively common in its range.

The White-winged Junco (J. hyemalis aikeni) has a pale gray head, breast, and upperparts with white wing bars. Females are washed brownish. It is an endemic breeder in the Black Hills area of South Dakota, Wyoming, Nebraska, and Montana. It is common across its breeding range.
The Oregon Junco (J. hyemalis oreganus) is found on the Pacific coast mountains from southeastern Alaska to extreme northern Baja California. It has a blackish-gray head and breast with a brown back and wings and reddish flanks. This is the most common form in the west.

The Pink-sided Junco (J. hyemalis mearnsi) has a grey head and breast, with a brown back and wings. It has pinkish-brown flanks. It is found in the northern Rocky Mountains from southern Alberta, Canada to Idaho and Wyoming in the northern United States.

The Gray-headed Junco (J. hyemalis caniceps) is found in the southern Rocky Mountains from Colorado to central Arizona. It is mainly grey on with a rusty back.

The Red-backed Junco (J. hyemalis dorsalis) is found in the southern mountains of Arizona and New Mexico. It differs from "Gray-headed" Junco in having a dark upper mandible, a variable amount of rust on the wings, and pale underparts. This makes it similar to the Yellow-eyed Junco except for the dark eye. It does not overlap with Yellow-eyed Junco in breeding range.

Their breeding habitat is coniferous or mixed forest areas throughout North America. They usually nest in a cup shaped depression on the ground, well hidden by vegetation or other material, although they are sometimes found in the lower branches of a shrub or tree. The nests have an outer diameter of about 10cm and are lined with fine grasses and hair.

Normally two broods of 4 eggs are laid during the breeding season. They are incubated by the female for 12 to 13 days. The slightly glossy egg shells are greyish or pale bluish-white in color and heavily spotted (sometimes splotched) with various shades of brown, purple or grey. The spotting is concentrated at the large end of the egg. Young leave nest between 11 and 14 days of hatching.

Northern birds migrate further south; many populations are permanent residents or altitudinal migrants. In winter, juncos are familiar in and around towns. The Slate-coloured Junco is a rare vagrant to western Europe and has wintered in Great Britain, usually in a domestic garden.

Malachite Kingfisher, Lake Nakuru National Park, Kenya

Malachite Kingfisher (Alcedo cristata) is a river kingfisher which is widely distributed in Africa south of the Sahara. It is largely resident except for seasonal climate related movements.

This is a small kingfisher, 13 cm in length. The general colour of the upper parts of the adult bird is bright metallic blue. The head has a short crest of black and blue feathers, which gives rise to the scientific name. The face, cheeks and underparts are rufous and there are white patches on the throat and rear neck sides.

The bill is black in young birds and reddish orange in adults; the legs are bright red. Sexes are similar, but juveniles are a duller version of the adult.

This is a common species of reeds and rank vegetation near slow moving water or ponds. The flight of the Malachite Kingfisher is rapid, the short rounded wings whirring until they appear a mere blur. It usually flies low over water.

The bird has regular perches or stands from which it fishes. These are usually low over the water. It sits upright, its tail pointed downwards. It drops suddenly with a splash and usually returns at once with a struggling captive.

Large food items are beaten on a bough or rail; small fish and insects are promptly swallowed. A fish is usually lifted and carried by its middle, but its position is changed, sometimes by tossing it into the air, before it is swallowed head downwards. Fish, aquatic insects and crustaceans are eaten.

The nest is a tunnel in a sandy bank, usually, though not always, over water. Both birds excavate. Most burrows incline upward before the nesting chamber is reached.

There is no nest, but three or four clutches of 3-6 round white eggs are placed on a litter of fish bones and disgorged pellets.

The call of this kingfisher is then a short shrill seek. The breeding song is a chuckling li-cha-cha-chui-chui.

There is a closely related species in Madagascar, the Madagascar Malachite Kingfisher, or Malagasy Kingfisher, (Alcedo vintsiodes). This has a black bill and greenish crest, and is not quite as dependent on water as the African species. It is otherwise similar in plumage and behaviour to the more widespread species.

Hummingbird

The Anna's Hummingbird (Calypte anna) is a medium-sized hummingbird.

These hummingbirds are glossy green on the back and grey below with green flanks. Their bill is long, straight and slender. The adult male has a glossy red crown and throat and a dark tail. Anna's is the only hummingbird species with a red crown. Females and juveniles have a green crown, a grey throat with some red marking, and a dark tail with white tips.

Their breeding habitat is open wooded or shrubby areas and mountain meadows along the Pacific coast from British Columbia to Arizona. The female builds a large cup nest in a shrub or tree, sometimes in vines or on wires. The nest is round and about 1 1/2 to 2" in diameter. The nest is built of very small twigs, lichen and other mosses, and often lined with downy feathers or animal hair. The nest materials are bound together with spider silk or other sticky materials. They are known to nest early as mid-December and as late as June.

These birds are permanent residents in parts of their range. Some birds may wander north to southern Alaska, south to Mexico or move east from California after nesting season. Some individuals have been banded as far east as Alabama and Florida.

These birds feed on nectar from flowers using a long extendable tongue or catch insects on the wing. While collecting nectar, they also assist in plant pollination. They sometimes eat tree sap.

Unlike most hummingbirds, this bird sings during courtship. They are very territorial.

This bird was named after Anna Massena, Duchess of Rivoli. A hybrid between this species and Allen's Hummingbird has been described as Floresi's Hummingbird, "Selasphorus" floresii (Ridgway, 1909; Taylor, 1909); the hybrid with the Black-chinned Hummingbird was called "Trochilus" violajugulum.