The gharial crocodile is perhaps one of the weirdest looking animals in the world. It is easily distinguishable from other species of crocodile due to its long narrow snout with males having a growth on top of the snout called a ghara which is a hindu word meaning pot. Their long jaws can hold up to 100 teeth.
The gharial population once existed from Pakistan to Myanmar but has now declined to just two countries. In india they are found along the Chambal Girwa and Son Rivers and in Nepal along the Narayani river.
Since the mid 1900`s the gharial population has declined by over 98% with only approximately 182 left in the wild. Additionally a continued 25% population decrease is projected. This has caused the IUCN to list it as critically endangered. More of that in a bit, first let’s get some information aboutt the gharial.
KNOWING MALE FROM FEMALE
The gharial is the only living crocodilian that can be sexually distinguished beyond body size: Females don’t have the gharas. At around 3 to 4.5 meters long, they're also much smaller than the males, which typically range from 4 to 6 meters in length. Some monstrous, 7 meter male specimens have been documented. Such huge individuals can weigh a whopping 800 kg, making them some of the heaviest reptiles on Earth. And yet in weight, they're completely upstaged by the famous saltwater crocodile, which can weigh more than a ton.
DIET
Whereas most crocodilians have rather broad snouts, a gharial’s is so long and thin that it looks like a toothy broomstick. Comical as these jaws may seem, the slender shape is perfectly designed for snapping up the animal’s favorite food: fish. The gharial snout can rapidly slice through the water with minimal resistance, and its jaws are equipped with 106 to 110 needle-like teeth, which interlock when the crocodilian snaps its mouth shut impaling any fish that happen to be between its jaws.
As it grows, a gharial’s snout changes shape, and its diet evolves accordingly. Since hatchlings have broader jaws than adults do, the youngsters mainly eat insects, crustaceans, and frogs. Over time, their snouts get thinner and longer and become ill-suited for snapping up the large land animals that other crocodilians tend to pursue. Full-grown gharials almost exclusively dine on fish, although big individuals sometimes gulp down the occasional bird, reptile, or small mammal.
A MALE’S GHARA IS USED TO EMIT BUZZING NOISES.
The ghara, which mainly consists of cartilage, is attached to a flap that partially covers the nostrils. When the male exhales, the flap starts vibrating, which can produce a long-range buzzing noise. It’s believed that this sound is used to communicate with females in mating season. Furthermore, males blow bubbles through their gharas during the courtship.
GHARIAL LEGS ARE SO WEAK THAT THEY CAN’T EVEN LIFT THEIR BELLIES OFF THE GROUND.
Normally, crocodilians keep their legs sprawled out to the sides on dry land. However, most species can also do what’s known as a “high walk.” To do so, the animals straighten their legs and raise their bellies high above the ground; this allows a crocodile or alligator to stride across rocky terrain without scratching up its underside. In general, the high walk is reserved for short forays, although some crocs—particularly juveniles—will use it during long-distance treks as well.
But to gharials, high walking isn’t an option. Compared to other crocodilians, this species has abnormally weak limb muscles—so when they're on land, gharials must resort to pushing themselves along on their stomachs. They're much better suited to swimming, and, in fact, it’s been argued that the gharial is the world’s most aquatic crocodilian. By and large, gharials only ever haul themselves ashore to bask or to lay their eggs.
THEY FORM HAREMS.
Once they reach sexual maturity at age 10, female gharials are inducted into a harem. Usually, these groups consist of four to six members who are jealously guarded by a resident bull male. Come mating season—which lasts from December to January—the resident bull breeds with all the females and fights to keep rival males at bay. Later, as the water levels recede during the dry months (March to May), the nesting season begins.
GHARIALS LAY THE LARGEST EGGS OF ANY CROCODILIAN.
Females looking to dig their nests will seek out deep sand banks, and the beaches of small, mid-river islands are considered ideal—predators will be less likely to disturb the eggs there. Using mainly her hind limbs, the female will create a pitcher-shaped burrow into which she'll deposit anywhere from 30 to 50 eggs. On average, each weighs about 0.3kg, making them the biggest eggs produced by any crocodilian.
Throughout the incubation period, the gharial will spend every night sitting beside her nest and every day keeping a close eye on it. Finally, after about 70 days, the eggs hatch into chirping, foot-long babies. Hearing their cries, the mother helps dig the newborns out of their burrow. They’ll spend a few months under her protection before striking out on their own.
THREATS
Overfishing, poaching, and habitat loss are all contributing to the decline of this species. Invasive prey items also bear some of the blame. In an attempt to boost the local fishing industry, African tilapia have been deliberately released into Indian rivers since the 1950s. It turns out that the foreign fish are terrible for gharials, which can die of gout after eating them. It’s believed that the tilapia contained chemicals from polluted rivers and when the gharials ate them, the toxins became concentrated, leading to gout. Or it’s possible that some unidentified toxin could be to blame.
Factors like these have put the gharial’s long-term survival in jeopardy. For millennia, they patrolled the rivers of Pakistan, Myanmar, Bangladesh, and Bhutan. But over the past century, they’ve gone extinct in all four countries. Today, the species occupies just 2 percent of its former range. According to the World Wildlife Federation, a meager 1100 wild gharials currently reside in India, while fewer than 100 holdouts live in Nepal. It’s estimated that the global population of adult specimens has fallen below 400.
On the positive side, there have been record hatchings in recent years, and this year, 2500 hatchlings were counted on the Chambal River. Hopefully, captive breeding efforts and education initiatives will be able to replenish their numbers.
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