Mugger  (Crocodylus palustris)

The broad snout of the mugger makes it look more like an alligator than a crocodile, but the large and visible fourth tooth indicates that it is a true crocodile. The head is flat with the eyes, ears and nostrils all on the top to allow the mugger to submerge the rest of the body, but still keep these sensory organs above the water. The eye is protected by a clear third eyelid for underwater vision, and the windpipe can be covered with a flap of skin to allow the crocodile to attack underwater without letting water into the lungs. The mugger has webbed feet, but these are not used in swimming, as they are tucked against the body whilst the flat tail propels the mugger through the water (3). Juveniles are light tan in colour with black cross-banding on the body and tail but this fades with age as the body becomes grey to brown (2). Males are larger than females (3).

The mugger is found in India, Iran, Nepal, Pakistan and Sri Lanka. It was found in Bangladesh, but is now thought to be extinct there (5).

Inhabits freshwater lakes, ponds and marshes, and may also be found in reservoirs, irrigation canals, human-made ponds and even coastal saltwater lagoons. The mugger prefers fairly shallow, calm waters (5).

The mugger is a highly social species that communicates through visual and audible signals, has a dominance hierarchy and exhibits territoriality. Males thrash their tails and lift their snouts to establish territories and gain dominance before courtship and mating. One month after mating, between February and April, the female lays 10 – 48 eggs in a nest site that she returns to every year for much of her life. After 55 – 75 days of incubation, the eggs hatch and the hatchlings are carried to water by the female and sometimes even the male (5). The sex of the hatchlings is determined by the temperature at which they incubate. Males result from eggs incubated at 32.5 ºC and females result from eggs incubated either above or below 32.5 ºC (2). The juvenile muggers remain in the territory for up to a year. They reach sexual maturity at six years (5).

Muggers consume crustaceans, insects and small fish when young, and move on to a diet of fish, frogs, crustaceans, birds, monkeys and squirrels in adulthood (2) (5).

Muggers have been used in traditional Indian medicine, and have been hunted for sport and for their skin, particularly during the 1950s and 1960s. Hunting for their skin was the major factor that contributed to the decline of the mugger, but it is no longer the primary pressure on this species (5). Habitat destruction for agricultural and industrial development (2), egg predation by humans and drowning in fishing nets are the current threats that face the mugger (5).

All wild populations of mugger are legally protected, and management programs intended to restore populations have been very successful (5). Widespread captive breeding programs have restocked wild populations and now have a surplus of captive-bred crocodiles as suitable habitat is limited. The Mugger Management Project in Similipal, India was started in 1979 and was able to rebuild populations, provide muggers for restocking elsewhere, and resort eventually to farming the crocodiles (6). The Indian government has now called an end to all captive breeding programs in India (2).

For further information on this species see the Wildlife Institute of India:
http://www.wii.gov.in/envis/crocodile/tnadu.htm and

Animal Diversity Web:
http://animaldiversity.ummz.umich.edu/site/accounts/information/Crocodylus_palustris.html

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk