Mugger or Marsh Crocodile
PHOTO CREDIT: F. Wayne King ( IUCN-CSG)
Local name: Mugger Much (Urdu)
Description and Biology:The mugger is a medium-sized crocodile (maximum length ca. 45m), and has the broadest snout of any living member of the genus Crocodylus.
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 (Whitaker and Whitaker 1989). Nests are located in a wide variety of habitats, and females have even been known to nest at the opening of, or inside, the burrow (B.C. Choudhury, pers. comm.). In captivity, some mugger crocodiles are known to lay two clutches in a single year (Whitaker and Whitaker 1984), but this has not been observed in the wild. Incubation is relatively short, typically lasting 5575 days (Whitaker 1987). Whitaker and Whitaker (1989) provide a good review of the behavior and ecology of this species. (information from IUCN's Crocodile Specialist Group).
Habitat and Distribution:Muggers are principally restricted to the Indian subcontinent where they may be found in a number of freshwater habitat ypes including rivers, lakes and marshes. In India and Sri Lanka, mugger crocodiles have adapted well to reservoirs, irrigation canals and man made ponds, and in some areas may even be found in coastal saltwater lagoons (Whitaker 1987, Whitaker and Whitaker 1989). In some areas of northern India and Nepal, mugger populations are sympatric with gharial, but the two species tend to be segregated by habitat. Where found together with gharial, muggers tend to bask in midstream on rocks or muddy banks (Groombridge 1982). This species, like a number of other crocodilians, is known to dig burrows.
No recent survey data is available on Mugger Crocodiles (Crocodylus palustris) in Pakistan, but this was considered endangered or very rare in the early 1980s (Groombridge 1982). 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). Approximately 50 individuals are held in captivity in seven facilities and three pairs are breeding. A program is ongoing to obtain muggers from the captive bred stock in India for release into protected habitats. Principal threats include killing for sale of the hide, killing by fishermen as well killing for the collection of specimens for laboratories and museums (Khan 1988) (information from IUCN 's Crocodile Specialist Group and Pakistan Convention on Biodiversity)
Conservation projects in Pakistan:Establishment of a conservation / management program in Pakistan: Recent reports suggest that mugger crocodile populations in Pakistan remain viable after being severely depleted by commercial hunting. However, no formal surveys have been conducted, and in some parts of the country continued killing has been reported. Interest has been expressed in initiating a restocking program similar to the one in India. However, surveys of population status and a biological research program are a prerequisite to establishing a management program (information from IUCN 's Crocodile Specialist Group).
Gharial or Gavial
PHOTO CREDIT: Tim Dwight( Wildldife Web)
Local name: Gharial (Urdu)
Description and Biology:The gharial is the most long-snouted and together with the saltwater crocodile the largest of the living crocodilians (males up to 67m). Placed in a family by itself, the Gavialidae, the gharial has long been separated from the rest of the crocodilian stock, with the possible exception of Tomistoma (Densmore 1983). Adult males grow a bulbous nasal appendage, which resembles an Indian pot called a 'ghara,' from which the species derives its name. 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 (Martin and Bellairs 1977). The gharial appears to be primarily a fish-eating species, but very large individuals are known to eat other prey. Females may not reach sexual maturity until they are nearly 3m long. Nesting is done during the annual dry season in holes excavated in river sand banks (Whitaker and Basu 1983). Unlike most other crocodilians who carry their young from the nest in the mouth, gharial appear not to do this because of the unusual morphology of their jaws (Singh and Bustard 1977). However, post-natal maternal care has been observed. Female gharial typically lay 3050 eggs, and the eggs are the largest of any crocodilian (average 160g) (information from IUCN 's Crocodile Specialist Group)
Habitat and Distribution: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 (information from IUCN 's Crocodile Specialist Group)
Conservation projects in Pakistan:Survey of status and distribution in Pakistan: The government of Pakistan is interested in implementing a restocking program similar to the ones in Nepal and India. However, apart from one recent sighting nothing is known about the status of the gharial. Surveys of the Indus River and Nara Canal are needed. Based on the results of this survey, action should be taken to set aside land for crocodile sanctuaries as a first step towards restocking (information from IUCN 's Crocodile Specialist Group)
Establishment of a captive rearing center in Pakistan: A captive rearing center similar to those in India and Nepal is needed to supply animals for restocking in protected areas (information from IUCN 's Crocodile Specialist Group)
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