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The Coscoroba Swan, Coscoroba coscoroba
is the smallest species of swan. However, it is still a fairly large species of waterfowl, averaging 4.2 kg (9.3 lbs), 1 m
(3.3 ft) long and 1.57 m (5.2 ft) across the wings. Like all other swans it belongs to the family Anatidae. Since it is only distantly related to the other swans, the Coscoroba Swan is placed on monotypic genus Coscoroba.
The Coscoroba Swan has white plumage except
for black tips to the outer six primary feathers, although this black is often barely visible on the closed wing. In flight,
the black wing tips are conspicuous. The bird has a red beak, legs and feet. They look somewhat more like geese than swans.
The female looks almost identical to the male. The cygnet is a patchy color, with brown and gray hues. The Coscoroba Swan
is also lacking the black mask that other swans have where their lores are between the eyes and beak. They look like a very
small swan in body and look like a goose in the head.
The Coscoroba Swan breeds in South America
from southern Chile and central Argentina south to Tierra del Fuego and the Falkland Islands. In winter it flies north to
central Chile, northern Argentina, Uruguay and the south east tip of Brazil.
The habitat is well-vegetated swamps and
lagoons, where it lives mainly on grasses and small water plants, but also mussels and fish. The population is estimated as
100,000 birds.
The female incubates the eggs, while the male stands guard and aggressively
helps to protect the fledglings against predators after hatching. Coscoroba Swans live to an age of approximately twenty years .
Black Swans are mostly black feathered, with a line of white flight feathers of the wing edges that
sometimes show when at rest, and are conspicuous in flight. The bill is bright red, with a pale bar and tip; and legs and
feet are greyish-black. Cobs (males) are slightly larger than pens (females), with a longer and straighter bill. Cygnets (immature
birds) are a greyish-brown with pale-edged feathers.
A mature Black Swan measures between 1.1 and 1.4 metres in length and weighs up to 9 kg. Its wing span, in flight,
is between 1.6 and 2 meters. The neck is long (relatively the longest neck among
the swans) and curved in an "S".
The Black Swan utters a musical and far reaching bugle-like sound, called either on the water or in flight, as well
as a range of softer crooning notes. It can also whistle, especially when disturbed while breeding and nesting.
The Black Swan is unlike any other Australian bird, although in poor light and at long range it may be confused with
a magpie-goose in flight. However the Black Swan can be distinguished by its much longer neck and slower wing beat.
The Black Swan is common in the wetlands of south western and eastern Australia
and adjacent coastal islands. In the south west the range encompasses an area between North West Cape, Cape Leeuwin and Eucla; while in the east it covers are large region bounded by the Atherton Tableland, the Eyre Peninsula and Tasmania, with the
Murray Darling Basin supporting very large populations of Black Swans. It
is uncommon in central and northern Australia.
The Black Swan’s preferred habitat extends across fresh, brackish and salt water lakes, swamps and rivers with
underwater and emergent vegetation for food and nesting materials. Permanent wetlands are preferred, including ornamental
lakes, but Black Swans can also be found in flooded pastures and tidal mudflats, and occasionally on the open sea near islands
or the shore.
Black Swans were once thought to be sedentary, but the species is now known to be highly nomadic. There is no set migratory
pattern, but rather opportunistic responses to either rainfall or drought. In high rainfall years, emigration occurs from
the south west and south east into the interior, with a reverse immigration to these heartlands in drier years. When rain
does fall in the arid central regions, Black Swans will migrate to these areas to nest and raise their young.
Black Swans, like many other water fowl, lose all their flight feathers at once when they moult after breeding, and
they are unable to fly for about a month. During this time they will usually settle on large, open waters for safety.
Behavior
When swimming, Black Swans hold their necks arched or erect, and often carry their feathers or wings raised in an aggressive
display. In flight, a wedge of Black Swans will form as a line or a V, with the individual birds flying strongly with undulating
long necks, making whistling sounds with their wings and baying, bugling or trumpeting calls.
Nesting Generally, Black Swans nest in the wetter winter months (February to September), occasionally
in large colonies. A typical clutch contains 4 to 7 greenish-white eggs that are incubated for about 35-40 days. After hatching the cygnets are tended by the parents for about 6 months until fledging,
and may ride on their parent's back for longer trips into deeper water.
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The Egyptian Goose (Alopochen aegyptiacus) is member of the duck, goose and swan family Anatidae. It is in the shelduck subfamily Tadorninae, and is the only extant member of the genus Alopochen. mtDNA cytochrome b sequence data suggests that the relationships of Alopochen to Tadorna need further investigation (Sraml et al. 1996).
Adult and goslings: This 63-73 cm long species breeds widely in Africa except deserts and dense forests, and is locally abundant. They
are found mostly in the Nile Valley and south of the Sahara. It is also introduced elsewhere; Great Britain and the Netherlands
have self-sustaining feral populations, the former dating back to the 18th century, though only formally added to the British list in 1971. In Britain,
it is found mainly in East Anglia, in parkland with lakes.
This is a largely terrestrial species, which will also perch readily on trees and buildings. It swims well, and in
flight looks heavy, more like a goose than a duck, hence the English name.
This species will nest in a large variety of situations, especially in holes in mature trees in parkland. Egyptian
Geese usually pair for life.
Gosling: The sexes of this striking species
are identical in plumage, though the males average slightly larger. There is a fair amount of variation in plumage tone, with
some birds greyer and others browner, but this is not sex or age related.
Egyptian geese typically eat seeds, leaves, grasses, and plant stems. Occasionally, they will eat locusts, worms, or
other small animals.
Egyptian geese were considered sacred by the ancient Egyptians, and appeared in much of their artwork. The Egyptian Goose is one of the species to which the Agreement on the Conservation of African-Eurasian
Migratory Waterbirds (AEWA) applies.
The Bar-headed Goose (Anser indicus) is a goose which breeds in Central Asia in colonies of thousands
near mountain lakes. It lays 3-8 eggs in a ground nest.
Preferred summer habitat is high altitude lakes where the bird grazes on short grass. It suffers predation from crows,
foxes, ravens, sea eagles and others. The total population may, however, be increasing.
The Bar-headed Goose migrates over the Himalayas to spend the winter in India, Assam, Northern Burma and the wetlands
of Pakistan.It migrates up to Magadi wetlands of Gadag district of Karnataka in the southern part of India. The winter habitat of the
Bar-headed Goose is on cultivation, and the bird feeds on barley, rice and wheat, and may damage crops.
The Bar-headed Goose is believed to be the highest flying bird having been seen at up to 10175 m (33,382 feet). It
has a slightly larger wing area for its weight than other geese. It is believed this helps the goose to fly so high.
The bird is pale grey, it is easily distinguished from any of the other grey geese of the genus Anser by the character implied by its English name. It is also much paler than the other geese in this genus. In flight, its
call is a typical goose honking. It has sometimes been separated from Anser, which has no other member indigenous to
the Indian region, nor any at all to the Ethiopian, Australian, or Neotropical regions, and placed in the monotypic genus Eulabeia. The Bar-headed Goose is often kept in captivity as it is considered beautiful
and breeds readily in captivity from which it sometimes escapes. Records in Britain are frequent, and almost certainly relate
to escapes - however, the species has bred on several occasions in recent years and around five pairs were recorded in 2002
(the most recent available report of the Rare Birds Breeding Panel). It is possible the species is becoming gradually more
established in the UK. The bird is sociable and causes no problems for other birds. The wild population is believed to be
declining due to over-hunting.
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