Friday, 10 June 2011

Reptiles of Pakistan

Reptiles of Pakistan

Over 195 species of reptiles are known in Pakistan. Of these, 13 species are believed to be endemic. As with other groups, these are a blend of Palaearctic, Indo-Malayan and Ethiopian forms.

The mugger (marsh crocodile) is in danger partially due to over hunting. The species is now nearly extinct and only occur in small numbers in Sindh and a few areas in Balochistan (Groombridge, 1988). The gharial is in a precarious situation, or maybe already extinct and has only been seen in small numbers between the Sukkur and Guddu barrages. In addition monitor species are heavily hunted for their skins.

Of the 72 snake species found in Pakistan, only 14 marine and 12 terrestrial snake species are poisonous; most well known are the Indian cobra, common krait, saw-scaled viper and Russel's viper.

On genus, the monospecific Teratolepsis, is endemic, while another, Eristicophis, is near endemic.The Chagai Desert is of particular interest for reptiles, with six species ( including five lizards and onesnake ) are endemic to Pakistan and a further six species found only here and in bordering parts of Iran. Important populations of marine turtles nest on Pakistan's southern beaches. Green and olive turtle, mugger, gharial, central Asian monitor, Indian python, central Asian cobra are among the internationally threatened species of reptiles in Pakistan (IUCN 1990).
Sea Turtles of Pakistan
Sea Turtles are a group of shelled reptiles and belong to the order Testudines or Chelonia. Also included within this order are the terrapins and tortoises. Within the Chelonia there are 13 families. The eight species of modern Sea Turtles are found within two of these, the Dermnochelyidae and the Cheloniidae. The first family has only one Sea Turtle, the Leatherback. The other seven species of Sea Turtle are found in the other family - the Cheloniidae. Sea Turtles are large animals, the Leatherback attaining a length of 2m and a weight of over 500 kg. (one caught off Wales in 1991 weighed 995 kg!!). 
In Pakistan family Dermnochelyidae is represented by a single species of turtle, the Leatherback Sea Turtle Family Cheloniidae is represented by four species of turtles: Green Sea Turtle, Olive Ridley Turtle, Hawksbill Turtle and the Lagger Headed Turtle.
Family: CHELONIIDAE (Marine Turtles)
This Family is represented in Pakistan by four species of marine turtles: Green Sea Turtle, Olive Ridley Turtle, Hawksbill Turtle and the Lagger Headed Turtle. Only 2 species are mentioned here:
·         Green Sea Turtle (Chelonia mydas japonica)
·         Olive Ridley Turtle (Lepidochelys olivacea olivacea)
The Green Turtle is the largest of the hard-shelled sea turtles (the Leatherback Dermochelys can grow much larger) although size, weight, and carapace shape can vary markedly between different populations. Average nesting female carapace length 80 to 110cm and weighs 110 to 185kg. The beaches of Pakistan are some of the most important nesting grounds for the Green Turtles. Each year thousands of female Green Turtles come to the beaches of Hawksbay and Sandspit off the coast of Karachi to lay their eggs. The Sind Wildlife Department in collaboration with WWF-Pakistan is working on a project for safe release of turtle hatchling to the Arabian sea since 1980's. Green Turtle nests are laid throughout the year, with most nests occurring between July and December. The egg are carefully kept in closed enclosers and released after the hatchlings are hatched. in Baluchistan Province (the Makran coast), may also hold significant numbers of sea turtles.
General characteristics:
The Olive Ridley is a small turtle, usually less than 100 pounds. Average nesting female carapace length 55 to 75cm and weighs 35kg. The overall color of this turtle is olive green.
The Olive Ridley is relatively rare in Pakistan, but nestings have been reported each year at Hawksbay and Sandspit beaches off the coast of karachi. Though, large arribadas occur in two beaches in Orissa State (north-east peninsular India), on the Bay of Bengal.
Monitor and Small Lizards of Pakistan

Family: VARIANIDAE (Monitor Lizards)
Family VARIANIDAE is represented today by at least 46 species of Monitor lizards in Africa, Asia and Australasia. They are represented by a single Genera Varanus. The Genus Varanus is represented in Pakistan by the following species and subspecies:
Family: UROMASTYCIDAE ( Spiny-tailed Lizards )
  • Baloch Sping-tailed Lizard  (Uromastyx asmussi )
  • Common or Indian Spiny-tailed Lizard (Uromastyx hardwickii)
Family: GEKKONIDAE ( Eyelid and Lidless Geckoes )
  • Leopard Gecko ( Eublepharis macularius )
This large varanid has a snout-vent length 815-900 mm, tail 1230 mm. The dorsum is olive to brown, with dark spottings. Ventrum yellowish, with or without dark spottings, especially under the neck.
Essentially a burrower, it is also a good tree climber. During rainy season it lives in tree holes feeding on birds and eggs, otherwise it burrows in hard soil. It often climbs into thatched houses to feed on nesting birds. The name of this monitor lizard is misleading, for it is one of the most widely distributed of the living varanids. The Bengal  monitor inhabits river valleys in eastern Iran, Afghanistan and western Pakistan (Mertens 1942, 1959; Leviton & Anderson 1970; Luxmoore & Groombridge 1990). Elsewhere in Pakistan it is widespread in many different habitats, but reaches greatest abundance in agricultural areas (Auffenberg et al 1991). This large varanid  frequents moderately dry  forests, and extends into cultivated areas, where  it  inhabits tracts of barren badland. It often invades inhabited houses, attracted by poultry and rodents. In Pakistan,  it is reported  from  throughout  the plains  of Punjab and Sindh, sub-Himalayan tracts, Waziristan and extends westward into southeastern Iran and eastern Afghanistan.
Local Name:
Goa (Urdu)

The Yellow Monitor has a snout-vent length 500-515 mm, tail 575-600 mm. The dorsum reddish brown, body and tail barred with alternating dark-edged reddish brown and dirty yellow bars, ventrum light yellow. It is a lizard of seasonally flooded forests, and marshy areas in flood plains of the Indus River and its tributaries. It extends into tilled fields along water courses with mesic habitat, and usually burrows in the roots of trees and other vegetation. This varanid has a restricted distribution range. It has been reported from Salt Range and District  Sialkot in northern Punjab , and the Sindh Delta in Pakistan . It is known to extend to the western Bengal . 

Crocodilians (crocodiles, alligators, caimans, and gharials), are prominent and widespread occupants of tropical and subtropical aquatic habitats. There are 23 living crocodilian species in the world represented by three families, ALLIGATORIDAE, CROCODYLIDAE and GAVIALIDAE. In Pakistan two families are represented by two species of Crocodilians.

Family: CROCODYLIDAE (Crocodiles)
This Family is represented in Pakistan by a single species of crocodilian The Mugger, belonging to the Genus Crocodylus:
Family: GAVIALIDAE (Gharial)

This Family is represented in Pakistan by a single species of crocodilian Indian Gharial, belonging to the Genus Gavialis:
Mugger or Marsh Crocodile
Crocodylus palustris
The mugger is a medium-sized crocodile (maximum length ca. 45m), and has the broadest snout of any living member of the genus Crocodylus. The colour generally is light tan in juveniles, with black cross-banding on body and tail. Adults are generally grey to brown. Mugger crocodiles are a hole nesting species. As with other hole nesters, egg laying takes place during the annual dry season. Females become sexually mature at a length of approximately 1.82m, and lay 2530 eggs. In Pakistan, the mugger is reported to be extinct in the Punjab province due to alteration of habitat (Chaudhury 1993). Small populations are reported in Sind along the Nara Canal, in Khairpur Sanghar and Nawab districts and Haleji lake. These are said to be vulnerable and diminishing. The most recent survey was conducted by the zoological survey of Pakistan during 1997. Five hundred specimens were recorded at Makhi and Baqar Dhand of the Chotiiari reservoir. Plans for winter survey during 1999- 2000 season are under way. One thousand specimens were recorded in 1999 in Sanghar district by the Sind wildlife department. The species is now considered safe in Sind. Crocodile recovery has been in association with a conservation project in the Deh Akro no. 2 Taluka Nawabshah reservior, downstream from the Sukkur Barrage near Rohri. The project began in 1983, and current estimates place the crocodile population at about 2000 (Ahmad 1990).

The mugger remains widely distributed in Baluchistan with confirmed locations on the Nari, Hab, Titiani, Hingol and Dasht rivers and Nahang and Kach Kuar. In all cases the populations are of unknown but small size. In Balochistan, the widespread killing of crocodiles has threatened the majority of the local populations. Many crocodiles were reported killed in the River Hingol during a period of low water in 1986-1987 (Khan 1989).
Indian Gharial or Gavial
Gavialis gangeticus
Local Name:
Gharial (Urdu)
Gharial are arguably the most thoroughly aquatic of the extant crocodilians, and adults apparently do not have the ability to walk in a semi-upright stance as other crocodilians do (Bustard and Singh 1978). Although the function of the ghara is not well understood, it is apparently used as a visual sex indicator, as a sound resonator, or for bubbling or other associated sexual behaviors. The diet changes between juvenile and adult - the juveniles are well suited to deal with a variety of invertebrate prey such as insects, plus smaller vertebrates such as frogs. Adults, however, are primarily fish-eaters, for which their jaws and teeth are perfectly adapted. The gharial is considered to be one of the most critically threatened of all crocodilians, becoming alarmingly close to extinction in the 1970s. Gharial are extremely rare in both India and Nepal, virtually extirpated in Pakistan, Bhutan and Bangladesh, and probably extinct in Myanmar.

Gharial are restricted to the northern part of the Indian subcontinent where they were found in four river systems: the Indus (Pakistan), the Ganges (India and Nepal), the Mahanadi (India) and the Brahmaputra (Bangladesh, India and Bhutan). Reports of gharial remaining in the Sind region of Pakistan are persistent (Ahmad 1990, Chaudhry 1993), but there appears to be a very small number, possibly only one or two individuals. The species is virtually extinct in Pakistan. The Pakistan government is currently planning a restocking effort with assistance from Indian institutions.

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