Tuesday, November 30, 2010

The Most Poisonous Snake........

Belcher's sea snake
The Belcher's sea snake (Hydrophis belcheri) is a species of sea snake. It is the most toxic snake in the world. Just one drop can kill more than 1000 people. But, it has a friendly temperament and would normally have to be subjected to severe mistreatment before biting. Usually those bitten are fishermen handling nets, although only a quarter of those bitten are envenomated since the snake rarely injects much of its venom. Because of this, and its docile nature, it is generally not regarded as very dangerous.
Description
The faint-banded sea snake is of moderate size, ranging from 0.5 to 1 meter in adult length. Its thin body is usually chrome yellowish in color and is surrounded by dark greenish bands. Head is short and has same colour as that of bands. Its mouth is very small but suitable for aquatic life. Its body when viewed outside water appears having fainted yellow colour. Its scales are different from other snakes and they overlap each other. Dorsal pattern does not extend on to venter; it has scales with a central tubercle. It is highly compressed at the rear end of the body and has a short head. Abdominal board is very narrow or non-existent.
Like other sea snakes, it has a paddle-like tail which makes it an expert swimmer; it rarely goes on land, and eats fish and shellfish. It breaths air, has valves over its nostrils that close underwater. It can hold its breath for as long as 7 to 8 hours while hunting and even sleeping but then has to come over water surface for a quick breath of air. It is generally docile and not aggressive at all. It may deliver a provoked bite only after repeated severe treatment. It usually bites fishermen handling nets but only 25% of those bitten are envenomed.

Distribution

Indian Ocean (Philippines: Visayan area, Panay; New Guinea), Gulf of Thailand, Australia, Solomon Islands [McCoy 2000]. Especially around the Ashmore Reef in the Timor Sea off northwest Australia.

Thursday, November 25, 2010

The fastest BIRD.....


The Peregrine Falcon

The Peregrine Falcon (Falco peregrinus), also known as the Peregrine,and historically as the "Duck Hawk" in North America, is a cosmopolitan bird of prey in the family Falconidae. The Peregrine is renowned for its speed, reaching speeds of over 320 km/h (200 mph) during its characteristic hunting stoop, making it the fastest extant member of the known animal kingdom.
It is a large, crow-sized falcon, with a blue-gray back, barred white underparts, and a black head and "moustache". Experts recognize 17 to 19 subspecies which vary in appearance and range; there is disagreement over whether the distinctive Barbary Falcon is a subspecies or a distinct species. Typical of bird-eating raptors, all subspecies of F. peregrinus, including the nominate, aresexually dimorphic, with females being considerably larger than males.
The Peregrine's breeding range includes land regions from the Arctic tundra to the Tropics. It can be found nearly everywhere on Earth, except extreme polar regions, very high mountains, and most tropical rainforests; the only major ice-free landmass from which it is entirely absent is New Zealand. This fact makes it the world's most widespread bird of prey.Both the English and scientific names of this species mean "wandering falcon", referring to the migratory habits of many northern populations.
While its diet consists almost exclusively of medium-sized birds, the Peregrine will occasionally hunt small mammals, small reptiles or even insects. Reaching sexual maturity at one year, it mates for life and nests in a scrape, normally on cliff edges or, in recent times, on tall human-made structures.The Peregrine Falcon became an endangered species in many areas due to the use of pesticides, especially DDT. Since the ban on DDT from the beginning of the 1970s onwards, the populations recovered, supported by large scale protection of nesting places and releases to the wild.

Description

The Peregrine Falcon has a body length of 34 to 58 centimetres (13–23 in) and a wingspan of around 80 to 120 centimetres (31–47 in). The male and female have similar markings andplumage, but as in many birds of prey the Peregrine Falcon displays marked reverse sexual dimorphism in size, with the female measuring up to 30 percent larger than the male. Males weigh 440 to 750 grams (0.97–1.7 lb) and the noticeably larger females weigh 910 to 1,500 grams (2.0–3.3 lb); for variation in weight between subspecies, see under that section below.
The back and the long pointed wings of the adult are usually bluish black to slate gray with indistinct darker barring; the wingtips are black. The white to rusty underparts are barred with thin clean bands of dark brown or black. The tail, colored like the back but with thin clean bars, is long, narrow and rounded at the end with a black tip and a white band at the very end. The top of the head and a "mustache" along the cheeks are black, contrasting sharply with the pale sides of the neck and white throat. The cere is yellow, as are the feet, and the beak and claws are black. The upper beak is notched near the tip, an adaptation which enables falcons to kill prey by severing the spinal column at the neck. The immature bird is much browner with streaked, rather than barred, underparts, and has a pale bluish cere and orbital ring.

Feeding

Immature using a USFWS ship as a perch on which to eat its prey.
The Peregrine Falcon feeds almost exclusively on medium sized birds such as doves, waterfowl,songbirds, waders and pigeons. Worldwide, it is estimated that between 1,500 and 2,000 bird species (up to roughly a fifth of the world's bird species) are predated by these falcons. In North America, prey has varied in size from 3-g hummingbirds to a 3.1-kg Sandhill Crane (killed by a peregrine in a swoop). Prey also include the small raptor, the American Kestrel. Other than bats taken at night, it rarely hunts small mammals, but will on occasion take rats, voles, hares, mice and squirrels; the coastal populations of the large subspecies pealei feed almost exclusively on seabirds. In the Brazilian mangrove swamp of Cubatão, a wintering falcon of the subspeciestundrius was observed while successfully hunting a juvenile Scarlet Ibis. Insects and reptiles make up a small proportion of the diet, which varies greatly depending on what prey is available. In urban areas, the main item of the Peregrine's diet is the Rock or Feral Pigeon, which comprise 80% or more of the dietary intake for peregrines in some cities. Other common city birds are also taken regularly, such as Mourning Doves, Common Swifts, Northern Flickers, Common Starlings, American Robins and various corvids.
The Peregrine Falcon hunts at dawn and dusk, when prey are most active, but in cities also nocturnally, particularly during migration periods when hunting at night may become prevalent. Nocturnal migrants taken by Peregrines include species as diverse as Yellow-billed Cuckoo,Black-necked Grebe, Virginia Rail and Common Quail. It requires open space in order to hunt, and therefore often hunts over open water, marshes, valleys, fields and tundra. It searches for prey either from a high perch or from the air. Once prey is spotted, it begins its stoop, folding back the tail and wings, with feet tucked. The air pressure from a 200 mph (320 km/h) dive could possibly damage a bird's lungs, but small bony tubercles on a falcon's nostrils guide the powerful airflow away from the nostrils, enabling the bird to breathe more easily while diving by reducing the change in air pressure. To protect their eyes, the falcons use their nictitating membranes (third eyelids) to spread tears and clear debris from their eyes while maintaining vision. Prey is struck and captured in mid-air; the Peregrine Falcon strikes its prey with a clenched foot, stunning or killing it, then turns to catch it in mid-air. The Peregrine will drop it to the ground and eat it there if it is too heavy to carry. Prey is plucked before consumption.