Our Herp Class: Natural History of the Gharial: A very unusual and rare reptile

For this blog I chose to do a reptile that is very rare and is probably one I will never see in person... The Gharial.

Taxonomy
Order: Crocodylia
Family: Gavialidae
Genus/species: Gavialis gangeticus

Common name: Gharial or Gavial

About the Gharial

The Gharial is know for its very long and narrow snout which will become shorter and thicker as it ages. In mature gharial, a growth will form on the tip of the male's snout called a "Ghara" which is the indian word for pot and is where this reptile gets its name. Though not too much is know about the "Ghara," two possible functions for it are thought to be: it is a vocal resonator which produces a buzzing noise when it tries to communicate and it is a visual sign for female gharial. The gharial mainly feeds on fish and is one of the largest species of crocodilian. Males can reach a maximum size of 20 to 23 feet in length. The gharial's body structure suggests it is strictly designed to live in water. They are very good swimmers, their tails are well developed and flattened for swimming and their feet are extensively webbed. However, their movement on land is very poor. The structure and musculature of their legs are not suited to allow the gharial to raise its body off of the ground so when it is out of water it pushes its body across the ground while sliding on its stomach. There can be as many as 110 teeth in the gharial's snout. They can live 40 to 60 years in the wild.

An example of a male gharial with the "Ghara" on it's snout

HabitatsGharials are found in the rivers of the northern India subcontinent, in Bangladesh, Bhutan (possibly extirpated), India, Burma, Nepal and Pakistan. They are found within the river systems of the Brahmaputra (Bhutan and India), the Indus (Pakistan), the Ganges (India and Nepal), and the Mahanadi (India), with small populations in the Kaladan and the Irrawaddy in Burma. They prefer to live in calmer waters of deep rivers and will usually only leave the waters to make nests and lay eggs or bask, both of these activities take place on the sand banks so the gharial do not move too far away from the rivers.

Distribution of the Gharial

Diets

Early on in the gharial's life it will feed on small insects, small invertebrates and small fish. As it matures it will eventually eat larger fish. Sometimes adult gharials will eat small mammals trying to cross rivers as well. The gharial hunts by either actively swimming around the water and catching fish or by sitting in rushing water with its mouth open and waiting to feel a fish swim into its snout. Large animals are unable to be eaten by the gharial due to the structure of it's snout. A gharial is unable to attack larger animals for it would damage even snap its long and narrow snout which is why it mainly sticks to fish and also helps to address a myth about the gharial which will be discussed later.

Reproduction

Males and females reach sexual maturity around 8 to 9 feet. This is also when the males "Ghala" starts to form. The male and female will mate for as long as thirty minutes during the mating season which last about two months during December and January. Then nesting occurs from March to May. During this time the females go on to shore and unlike other crocs, create hole nests. The females may make many false holes before selecting the right one. They then lay about 60 eggs. The gharial's eggs are the largest of all crocs. The female will guard the eggs for 80 to 90 days and then help the hatchlings into the water.

Conservation Status

The gharials are listed as critically endangered and are severely threatened due to habitat loss from human destruction. In the 1970s the gharial population was nearly extinct and has since made some recovery but it is still very threatened. There are many plans being carried out to help save the few populations left. One major problem is the gharial is not wide spread and has not been studied too much so until more research is done on them, conservation efforts will not be as effective as they need to be.

Myth: Human hunters

A common myth about the gharials is that they hunt humans. As stated earlier, the structure of the gharials snout severely inhibits its ability to attach large prey. A bite from them could cause flesh wounds but a gharial though dangerous and potentially deadly, would not hunt humans because it could mean certain death for them if their snout were to be rendered ineffective after an attack. A gharial could probably do more damage with its tail which could be used as a whip and break bones. There have been less than five documented gharial attacks on humans (obviously some attacks may not be documented due to the development of some places people may live in along rivers) and these attacks were due to people getting too close to nests, not the gharials hunting. A reason why this myth may have been started is because human valuables and remains have been found in the stomachs of gharials such as clothing and jewelry. But a simple explanation for this is that in India and Pakistan something done frequently is corpses are sent down rivers as practiced by the Hindi religion. Corpses will likely have clothing and jewelry on them as they are sent down the rivers toward the habitats of gharials. A gharial can still be very dangerous but all evidence shows that they do not intentionally hunt humans.