the Legacy continues…………………….
Gregory R. Mann, Ph.D. {ret.}

Mugger Crocodile

“Crocodylus palustris”

The Mugger Crocodile is a true crocodile but is one of the most like an alligator of all crocodiles, both in what it looks like as well as how it lives & behaves. These are mostly freshwater crocodiles (although they have been sighted in brackish water) that prefer rivers, lakes, artificial water tanks, reservoirs and irrigation systems. Mugger Crocodiles live all over the Indian subcontinent from eastern Iran, Pakistan, northern India and Nepal. They are also found south of the Himalayas near Bangladesh and south to Sri Lanka. They is a fairly large sized crocodile and can reach about 15-16 feet in length. Generally the male Mugger Crocodile will weigh more than the female and be longer. The Mugger has a very broad snout, which is what primarily gives them the look of an American alligator. Their head is fairly flattened on the top and the eyes, ears and nostrils are on the same surface. This permits the Mugger Crocodile to both see & hear nearly all the way under the water. The eyes of the Mugger Crocodile are kept protected by the presence of a third eyelid, which is called a nictitating membrane. This nictitating membrane is crystal clear to permit the crocodile to see and keep the water out of the eye. Inside their mouths will be about 68 teeth, which is part of what will distinguish the crocodile from an alligator. Mugger Crocodile teeth are aligned perfectly with each other, while those of an alligator are not so, but instead are jagged in growth. Muggers are ambushers and stake out river banks where large mammals are known to frequent. When said mammal comes down to drink, the Mugger Crocodile is quick to take up a position upon which it may strike out and seize it’s prey. Adults are large animals weighing in at at least 1,000 pounds and have no trouble holding down a large deer or buffalo. When the animal is in position it waits for just the right moment and then it strikes. Surging onto land with jaws agape and ready to snap shut the mugger is quick to grab it’s prey. Once grabbed usually on the muzzle or foreleg, the animal is brought underwater where it soon drowns and the Mugger Crocodile will begin eating the animal.

It is not uncommon to see a pack of Mugger Crocodiles cooperating to take down a large animal and then dismember it. As far as small animals go, muggers will grab what they can when they can. Adults have been seen sweeping their large heads through the water to grab little fish. Tail walking has also been observed in Mugger Crocodiles as they grab low flying birds. Smaller animals are probably taken as they swim across the river or lake. Hatchlings make a living off of insects and crustaceans, while juveniles prefer fish and small vertebrates. Medium-sized adults will eat frogs, lizards, birds and small mammals. Muggers are also known for stealing fish from nets. The Mugger Crocodile like all crocodilians, is an excellent swimmer and uses his flat tail to propel himself forward in the water. They have webbed feet however these are not used for swimming. The body of the Mugger Crocodile is well armored by a scaly hide with larger scutes on the neck that look much like the American Alligator. The adult is gray or brown, while the smaller juveniles are about 10 inches long and are lighter tan, with bands of black on the tail and the back. The Mugger Crocodile is a good traveler even on land and if the pool of freshwater they live is dries up, they will travel a long distance to find more water. The females begin to breed at about 6 years of age while the males are not mature enough until about 10 years of age. The female can then breed until she is about 30 years old. During courtship time, males will cruise the perimeter of their territory with their back & tail out of the water to show dominance. This is also followed by jaw slaps which is used to warn males and more importantly, guide females to his territory. When a female finds the male, it is up to her to let him know that she is ready to breed. She does this by rubbing her snout on him and circling around him. Sometimes even mounting him. The male will then follow up with underwater bubble-blowing underneath the female to assure her readiness. If she agrees he will mount her and they will begin copulating on the surface before submerging for 10-15 minutes. Afterwards the female will stake out her claim on a sloping-type riverbank for best nest site. She will rigorously defend this site from other females and males that get too close and 40 days later on the average, she is ready to lay her eggs. The female will dig many trial holes in search of the ones with the best spot on the river and best overall temperature. When the temperature is around 800-820F, she will dig her true nest. The temperature of the nest is what will determine whether the young are male or female. If it is about 32.5C the embryos are all males. Between 28-31C all the animals will be females. This hole will be L-shaped and reach as far down as her hind-legs can go. There she will deposit between 25-35 (although there have been reports of as many as 46) eggs in the hole. All the while, she will be in that trademark trance that female reptiles seem to get in during egg laying. These trances are so deep that researchers can actually come up and pet the female without her caring. When all the eggs have been laid, the female then must cover them up once more. This part is long and tedious sometimes taking up to an hour or more as the female first covers and then camouflages the nest. For the next 2 months, the female will stand guard over the nest ready to attack any intruders into her territory. The female does protect the nest and will guard it until the young hatch. When they do, both mother & father will take the young to the water and they will stay with the parents until about a year old. The adults capture large prey such as fish, turtles, snakes and sometimes even monkeys, deer and buffalo to eat. In the early 1800’s, there were thought to be many thousands of Mugger Crocodiles and the species was common throughout India where it was seen on a daily bases, but hunting & trapping brought the population of Muggers to the brink of extinction. In 1867, the last sighting of a Mugger Crocodile in Myanmar took place. In the 1970’s, awareness of the problems for the crocodiles saw new laws enacted and captive breeding brought the wild population up to 5,000.