Gharial: Gavialidae
Behavior And Reproduction
Like some of the other alligators and crocodiles, gharials usually get along quite well and live together in groups. They stay in the water most of the time, coming out occasionally to bask on shore. While they are excellent swimmers, they are slow on land and must drag their bellies and tails on the ground when they walk. They rarely wander too far from the water's edge and, at the slightest threat, will dive back into the safety of the river. On especially warm days, they may open their mouths wide to cool off. This serves the same purpose as panting does for a dog.
When mating season arrives in December and January, the adult males begin fighting one another to set up and defend territories in shallow water. Their fights look something like wrestling matches. Two males lie side by side, lift their heads out of the water, and begin pushing each other with their snouts. The winner is the one that can topple over the other. Sometimes, the wrestling matches become more violent, and the two males hit each other with their snouts or bite each other. A male with a good territory may be able to attract several large females to mate with him. Scientists also believe that the size of the male's ghara may also be important during the mating season. The males can use the ghara to produce a loud buzz, which may be attractive to females. Males also will buzz to warn other males to stay away.
After mating, a female will lay her eggs sometime from March to May. She crawls up a steep bank at the riverside and begins looking for a spot for her nest. She digs her nest in dry ground at least 5 feet (1.5 meters) above water level. A female gharial is very fussy about her nest and may change her mind several times, even after starting to dig, before settling on the perfect place to lay her eggs. The female becomes territorial and guards her specific nest sites from other females, although she will share the beach with many other females and their nests. After digging a hole in the sand, she lays her eggs inside and carefully covers them. The smallest females lay as few as a dozen eggs, and many first-time mothers lay eggs that never hatch at all. The largest females, on the other hand, may lay almost 100 eggs. A typical gharial egg is 2.2 inches (5.5 centimeters) wide, 3.4 inches (8.6 centimeters) long, and weighs 5.5 ounces (156 grams). Females remain near their nests and will defend them from predators, if necessary. The eggs hatch 53 to 92 days later, with nests in warmest climates hatching out earliest and babies in the coolest areas breaking out of their eggs last. The temperature of the nest also controls the number of males and females. Especially warm nests produce more males, and cooler ones produce more females.
The mother gharial helps her young out of the nest, and then she and possibly the father watch over them. Despite this care, many of a female's young do not survive. Numerous animals, including pigs, hyenas, monitor lizards, and some humans, are fond of gharial eggs, while some birds and turtles often gobble up babies. In addition, the babies are born during the monsoon season and often drown in the floods that are common at this time of year. Of those that do survive, the females are ready to mate when they reach about 10 feet (3 meters) long and are at least 8 years old. The males can mate once they are 15 years old and about 11.5 feet (3.5 meters) long.
Additional topics
Animal Life ResourceDinosaurs, Snakes, and Other ReptilesGharial: Gavialidae - Physical Characteristics, Habitat, Diet, Behavior And Reproduction, Conservation Status - GEOGRAPHIC RANGE, GHARIALS AND PEOPLE