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Marsh Crocodile (Crocodylus palustris) Commonly known as "Mugger", this species is not only found in freshwater lakes,ponds, and marshes, but it has adapted well to reservoirs, irrigation canals, man-made ponds, and even recently in coastal saltwater lagoons.

Mugger crocodiles have the broadest snouts of all the crocodiles, giving them the appearance of the American alligator. The head is relatively flat on the top, with the eyes, ears, and nostrils all being on the same plane. This allows the crocodile to see, hear, and smell while almost completely submerged underwater. They are fair sized crocodiles, reaching maximum length of 16 ft. (5 mtrs.) and having an average length of 13 ft. (3.9 mtrs). The males are generally larger than the females. Mugger crocodiles have life spans of 40+ years. They are highly social and communicate with a wide variety of vocalizations. They will also socialize with other crocodilian species, especially the gharial. They must use heat acquired from the environment to regulate body temperature.

Colour is generally light tan in juveniles, with black cross banding on body and tail. Adults are generally grey to brown, with little banding remaining. Mugger crocodiles are excellent swimmers, using their flat tail to propel them. Their feet are webbed, but are not used for swimming. The body is well protected by a tough, scaly skin. The neck has large scutes. It's jaw contains 66-68 pointed teeth.

Mugger crocodiles have a very diverse appetite. The juveniles feed on invertebrates such as crustaceans and insects, and small vertebrates such as fish. Adults capture larger prey, such as fish, frogs, snakes, turtles, birds, and mammals such as squirrels, monkeys, deer and buffalo. Their social behavior include communication, gregarious behavior, dominance interactions, and territorial activities. At the age six, both male and female have reached their sexual maturity. This species of crocodile is a hole nesting species. Approximately one month after the mating, the eggs are deposited by the female into the nesting hole she has formed. This takes place between February - April and consists of an average 28 (10 - 48 range) eggs per clutch. The mugger is found primarily on the Indian subcontinent and extends into Pakistan and Sri Lanka.

Saltwater Crocodile (Crocodylus porosus ) Probably the largest of present day reptiles, the largest skull available measures 1 meter, male saltwater crocodiles can reach lengths of 23 feet and females reach lengths of over 10 feet. As its name implies, this species has a high tolerance for salinity, being found in brackish water around coastal areas and in rivers. However, it is also present in freshwater rivers, the estuarine crocodile is restricted in its distribution to the tidal estuaries, marine swamps, coastal brackish water lakes and lower reaches of the larger rivers. The saltwater crocodile has a vast geographical range that extends from Cochin on the west coast of India to the Sunderbans in West Bengal and to the Andaman Islands. However, it is also present in freshwater rivers and swamps. Movement between different habitats occurs between the dry and wet season.

Adult saltwater crocodiles are a dark colour with occasional tan or yellow spots. The underbelly is a pale white colour. This is a large headed species with a heavy set of jaws. A pair of ridges run from the eye orbits along the centre of the snout. Scales are more oval in shape than other species, and scutes are relatively small. The belly is creamy yellow to white in colour, except the tail that tends to be grey on the underside nearer the tip. Dark bands and stripes are present on the lower flanks, but do not extend onto the belly region.

Saltwater crocodiles are meat eaters. Juvenile crocodiles will eat small mammals, insects, shellfish, and fish. The larger the crocodile the more it can eat. Adult crocodiles will eat snakes, buffaloes, domestic cattle, and pretty much anything else it can get. They have been known to eat people. Breeding territories are established in freshwater areas. Females reach sexual maturity at length of 2.2 to 2.5 mts. (10 to 12 years old). Males mature later (3.2 mts., at around 16 years old). 40 to 60 eggs are usually laid (can range from 25 to 90). Juveniles hatch after around 90 days, although this varies with nest temperature. The female digs the young out of the nest when they start their characteristic chirping sounds. The highest percentage of males are produced around 31.6°C, with more females a few degrees above and below this. It is estimated that less than 1% of hatchlings will survive to reach maturity,

Gharial (Gavialis gangeticus) In India, they are found within the river systems of the Brahmaputra, the Ganges, and the Mahanadi, with small populations in the Kaladan. They are more adapted to an aquatic lifestyle in the calmer areas of deep, fast moving rivers. They usually leave the water only to bask and nest, both of which usually occur on sand banks.

Variation in snout shape occurs with age. It generally becomes proportionally shorter and thicker with age. The elongated jaws are lined with many interlocking, razor sharp teeth - an adaptation to the diet. The gharial is one of the largest of all crocodilian species, approaching C. porosus in maximum size - males reach at least 5 meters in length, and often approach 6 meters. The diet changes between juvenile and adult - the juveniles are well suited to deal with a variety of 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 teeth are ideally suited for holding struggling prey such as slippery fish). Some of the larger gharials can take larger prey, including mammals.

Females reach sexual maturity when they attain the length of around eight to nine feet (2.4 to 2.7 mts.). This is usually when they are older than seven years of age. The males do not mature until about 13 feet (3.9 mts.) in length at 15 to 18 years of age. The mating period occurs for two months during November, December and into January. Nesting occurs in March, April and May (the dry season) where hole nests are dug into sand banks. Between 30 and 50 eggs eggs are laid by female. The gharial is considered to be one of the most critically threatened of all crocodilians, and was alarmingly close to extinction in the 1970s.