Thursday 14 July 2011

Sheesh Nag, Kala Nag


FANGS FACT
Local Name: Sheesh Nag, Kala Nag (Urdu)
Family: ELAPIDAE
Genus: Naja
Status: Common
Warning: This snake is deadly poisonous. The venom is highly toxic. Snake bite symptoms begin approximately 8 minutes after bite.  Treatment should be given to the victim immediately if bitten
Indian Cobra (Naja naja naja), posterior view



Species and sub species:
Genus Naja is represented in Pakistan by two species and one subspecies:
  • Spectacled or Indian Cobra (Naja naja naja)
  • Central Asian/Oxus or Brown Cobra (Naja naja oxiana)
    Subspecies:
  • Black Pakistan Cobra (Naja naja karachiensis)
Description and Biology:
Two subspecies of cobras are found in Pakistan, the Indian or Spectacled cobra (Naja naja naja) and the Central Asian/Oxus or Brown cobra (Naja naja oxiana). Both these subspecies of cobra are about the same size. Average length is 1.9 meters, with a maximum length of 2.4 meters. N.n.naja has a spectacled marking on back of the neck (also visible from front on rare specimens). The hood appearance varies greatly. The body coloration is yellow to dark brown and black for both sexes. Males are generally heavier, shorter than females, but tails longer. N.n. oxiana is similar in appearence, but lacks the spectacle marking as in N.n.naja.

General characteristics:
The Indian or Spectacled cobra (N.n.naja) is a medium-sized, heavy snake; head not distinct from neck which is dilatable in life into a broad hood; loreal scale absent; single fang on each side, followed by 1—3 small solid teeth; scales smooth shiny, in 21—23 at midbody; ventrals 182—196, subcaudals 53—67. Single pair of prefrontals, absence of loreal scale and smooth dorsals.

Color very variable, from jet black, dark olive or dark brown dorsum. Ventrum pale gray to yellowish, with heavy slate gray or dark brown clouding. A spectacle mark on hood dorsum, and a ventral large ocellus, consisting of an outer yellow ring with central dark eye, mesially interrupted by ventrals, some are dark clouded. Variegated specimens with light-edged light brown scales are met with in Punjab, while jet black are very rare. Juvenile has speckled or uniform dorsal pattern. Snout-vent length 1658 mm, tail 269 mm.
 

Black Pakistan Cobra (Naja naja karachiensis), anterior view 
Photo Credit: David A. Northcott/CORBIS

The Central Asian/Oxus or Brown cobra has ventrals 191-210, subcaudals 62-71; single maxillary tooth (fang) on each side; juvenile pattern conspicuously banded, bands around the body.
Light yellowish to light brown, with or without a hoodmark. Some ventrals underhood dark. Ventrum clouded with black.
Snout-vent length 1370-1512 mm, tail 228-236 mm..


Central Asian/Oxus Cobra (N.n.oxiana)
Photo Credit: F.Tillack

Biology:
This cobra is diurnal; mostly active during evening and early morning. It may enter human dwellings when hunting.  It restlessly moves from place to place in search of prey, which mainly consists of mice, rats, poultry, frogs and snakes. Normaly, it is not considered aggressive, particularly shy of human beings and will avoid confrontation. Habitually it avoids confrontation with man, at a chance en-counter, first priority is to escape undetected. On sensing danger it lifts anterior part of its body to have a good look at its surroundings. If not provoked, it lets fall it's body and slips quietly away. However, if provoked, it hisses loudly and sways its hood to advertise its presence, and displays the hood markings to impress its adversary. It fixes its eyes to the source or annoyance, keenly following its movements. However, all the time at the lookout to have a chance to avoid conrontation and slip away. The swaying of hood with dorsal spectacle mark and ventral yellow ocellus, coupled with loud hiss, arc measures to just look as fearsome and as big as possible, to impress the enemy. Cobra attacks viciously and furiously, striking with full strength and biting savagely, chewing the bitten pan.  When bitting, it hold on and chews savagely. May strike repeatedly. This snake can be exceptionally quick-moving and agile. The fangs and venom glands of both subspecies are large. The venom is highly toxic. Snake bite symptoms begin approximately 8 minutes after bite. Victims experiences anxiety, the pulse quickens, grows weak and irregular. The victim soon falls into deep coma.

Pairings are known to be for life, breeding activity is observed from April to July, 12 to 30 eggs are laid in rat holes or crevices, female stays close until hatching.

Both the species feeds on rodents, birds, snakes, lizards, often enters inhabited houses attracted by rodents.

Habitat, Distribution and Status:
Cobra frequents different habitats: grasslands, vegetation along tilled fields, along water courses, semidesert forests, barns, ruins with grassy growths and around villages. It is plentiful in paddy growing areas, where it is attracted bv mice and poultry into living houses. It climbs into the branches of trees in search of nesting birds. Often it become resident in rat holes after consuming its occupant
 
N.n.naja is found in eastern Pakistan as far west as Karachi. It has been reported from sea level to 4000m in the Himalayas. It may be found in flat grasslands, among scattered trees, near rice fields and other cultivated areas, near settlements. Usually not found in deserts or rainforests.  This cobra species is found in Punjab, Baluchistan and Sind where it is quiet common. 

N.n.oxiana is rare in Pakistan and is found in Northern Pakistan at areas of elevations as high as 2,100 meters. It Inhabits dry wasteland, living in holes and crevices. In mountain areas lives in caverns and crevices and holes in rock. In Pakistan it extends throughout NWFP, northeastern Baluchistan to northwestern Punjab and Kashmir.

Subspecies N.n.karachiensis has been reported from Southern Pakistan.

Deforestation, reclamation and overgrazing are the main threats to the cobras in Pakistan. Every year thousands of cobras are killed in Pakistan for their skins. Snake charmers capture cobras to stage fights with mongoose in rural and urban areas. Cobras are locally used by aurevedic practitioners in their recipes. Due to constant human interference and indiscriminate killing of cobras, there is rapid depletion in populations of cobras throughout Pakistan.

Naja naja ()
Naja oxiana (
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