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Consider: the Gharial

Updated: Apr 19

Many animals specialize in a very particular prey or survival strategy. Consider the beaver, for example, with its ability to digest wood and chisel-like teeth designed to cut down trees, or the pearlfish, which has developed a variety of adaptations to serve its goal of living inside of a sea cucumber’s ass (thank God we don’t have those on land). These animals and many more have adapted to survive in very specific environments with very specific resources, and in that way they occupy niches in their ecosystems that would otherwise go unfilled. Specialization can be a double-edged sword, however; while it can drive a creature to become successful in its environment, it can also make survival difficult when environments change. If you take a beaver from its aquatic woodland habitat and throw it into a meadow without any trees, you will very soon have a very dead beaver. Remove a pearlfish from a sea cucumber ass, and you have a very relieved and grateful sea cucumber.

Just beneath the water of rivers and lakes on the Indian subcontinent lurks an animal unlike any other on Earth. This highly effective specialist hunter has adapted to survive by flipping the crocodilian playbook on its head. Yet, many of the same adaptations that make this animal so incredible have also caused it to struggle in the era of human land development and climate change. Consider: the gharial. Gavialis gangeticus.


Image Credit: Charles J Sharp under CC BY-SA 4.0

Gharials are the second largest crocodilian species on Earth, with a maximum length of 6 meters (20 feet). They possess many of the standard features you would expect out of a crocodilian, such as thick, rudder-like tails, bony plates along their backs, eyes at the tops of their heads, and long snouts. Adept swimmers and lightning-fast hunters, gharials only leave the water to sun themselves and lay their eggs. Because they rely so heavily on water, gharial legs are quite noodley and totally suck at supporting the animal on land. When they do leave the water, they tend to drag themselves along the ground like a seal or sea turtle.

I am sure you have noticed by now that a gharial looks kind of like an alligator who sneezed so hard its face exploded. This is because while many crocodilians put dinner on the table by ambushing prey from the water’s edge, gharials prefer to hunt fish. As such, they have incredibly long and skinny snouts designed for underwater hunting. The slim profile of a gharial’s snout allows it to pass through water with little resistance, giving them the ability to strike at fish much more quickly than a crocodile or alligator could. The long, needle-like teeth that line a gharial's mouth interlock when it closes, making escaping a gharial's bite nigh-impossible. As opposed to striking at fish head-on like an arrow or spear, gharials typically swim slightly past their targets, then swipe their snouts to the side, snagging their prey with a lightning-quick flick. Once they have successfully captured their prey, gharials swim to the surface and gulp it down whole. While gharial jaws kick ass in the water, their light weight and slim profile make them less than useful against large land animals—it’s kind of like trying to catch an antelope with a set of decorative-edge craft scissors. Not quite the right tool for the job.


Gharials sunning themselves along a river. Gharials only leave the water to bask and lay their eggs, and as such they struggle to move around on land. This is what can happen when your whole species decides to skip leg day at the gym. Image source: Shutterstock.

Uniquely among crocodilians, gharials exhibit sexual dimorphism, meaning that males and females possess slightly different traits (beyond the obvious point of genitals). Male gharials typically grow larger than females and possess a large bulb at the ends of their snouts called a “ghara”, named after a kind of traditional Indian pot designed to store drinking water. This ghara acts as a vocal resonator, allowing male gharials to attract mates through what I can only describe as sexy honking. Imagine if human men signaled they were ready for sex by releasing loud and obnoxious nose whistles, and imagine that a particularly robust nose whistle put nearby women in the mood. That is one way to attract attention at the club, I guess.

Male gharials establish harems, groups of breeding females who all mate with the same male (maybe they’re onto something with the nose whistle…). Once they mate, females climb up onto the shore within their male’s territory and dig a burrow in the sand in which they will lay 30 to 50 eggs. Once they have finished, the females will bury their eggs in order to help keep them warm for the duration of their incubation. Males, in turn, guard the nests from predators and fend off other males who might want to steal their girls or dig up their babies.


70 days later, when the time comes to hatch, the baby gharials call out to their mother from inside of their eggs using a high-pitched croaking noise that sounds uncannily like the laser sound effects from Star Wars. This signals the mother to dig them up, and the babies then crawl out into the river to begin their lives. Like many crocodilians, mother gharials care for their young, protecting them from predators such as birds of prey, snakes, and male gharials, who will often mistake their own children for food (I never said they were very smart). The mothers in a harem often take turns babysitting each other's young, allowing each of them time to hunt for themselves. Young gharials tend to hunt smaller prey such as insects and frogs, then shift to a diet of fish as they age.

Ecologically, gharials function as important predators within their native rivers, increasing ecosystem diversity and helping to keep the balance between predator and prey. This is because gharials tend to eat large predatory fish, reducing their populations and allowing smaller fish species to build up their numbers. Without gharials around, these large predatory fish can become overpopulated and deplete the river of prey species, leading to a less-healthy ecosystem. A balanced ecosystem doesn't just benefit river denizens, though—it can actually improve yields of economically-important fish for local humans. Fishing communities with gharial populations have reported improved fishing stocks compared to communities without them. It turns out that the most economically-valuable fish to humans in those river ecosystems are the small prey species, and the presence of gharials boosts these species’ numbers. This one animal has the ability to improve its habitat in a way that benefits every living thing around, humans included (except for the fish that the gharials eat; they’re SOL).



A baby gharial at Kukrail Reserve Forest in Uttar Pradesh, India (who looks a little like he just realized that he left his homework on the school bus). Unlike many reptile species, crocodilians care for their young until they are old enough to fend for themselves. Image Credit: Snuhil3 under CC BY-SA.

Once upon a time, gharials lived across a vast swath of the Indian subcontinent, from Pakistan to Burma, but a variety of factors have decimated their populations. The species almost went completely extinct in the 1970s, but has made a recovery with the assistance of conservation efforts. Despite this success, fewer than 250 gharials remain in the wild, and many conservation groups rank them as one of the most-endangered reptiles on Earth.

As with many endangered aquatic species, commercial fishing threatens gharials. Their long snouts with their thin, snaggly teeth get easily snagged in fishing gear, especially gillnets. Even more pertinently, though, overfishing depletes rivers of the fish that gharials need to eat to survive. When humans remove too many small prey species from rivers, the larger predatory fish that gharials eat starve and die off, leaving little food for the gharials. While gharials can greatly improve the health of their ecosystems, they also rely on a healthy ecosystem to survive.

Climate change, too, poses a threat to gharials. As global temperatures warm, the Indian subcontinent has become hotter and the monsoon rains have become less predictable, leading to bodies of water shrinking or drying up completely. While other crocodilians can waddle across land to find new habitats, gharials can’t since they skipped leg day at the gym, so they often become stranded and end up cooking out in the sun. Human developments such as farming, sand mining, and the damming of rivers can cause these same effects. Humans also hunt gharials directly and their gharas are often sold on the black market as a medicinal tool to aid in male vitality. Whenever I read about the consumption of animal parts via black-market trading, it’s always for male vitality. Is Viagra really not enough for some people?

Human conservation efforts have made some progress on protecting gharials from extinction, but not without some significant challenges. While captive breeding projects have succeeded at raising gharials, all attempts at reintroducing the species to its former habitats have failed. As such, conservation efforts have focused on maintaining the populations that already exist. The Convention on International Trade in Endangered Species (CITES), an international treaty aimed to protect endangered species from poaching, bans the trafficking of gharial parts internationally. While CITES protection certainly benefits gharials, black market poaching operations still target them, and enforcing bans on poaching is famously difficult due to the remote areas where many species live. As of right now, five disconnected gharial populations remain within India and Nepal, and no wild gharials are known to live outside of these places. While wildlife reserves can protect gharials from some of the effects of land development and poaching, they certainly can't shield them from the effects of climate change.


The plight of the gharial once again reminds us that when nature suffers, so do people. The problems that affect gharials—overfishing, climate change, habitat destruction—also negatively impact human communities. Overfishing leads to lower populations of commercially-valuable fish species, causing starvation or economic turmoil for subsistence fishermen. The droughts caused by climate change also ruin crops, incite more frequent wildfires, and deprive people of safe drinking water. The displacement of natural habitats due to mining can lead to pollution, which harms human health. By protecting species like gharials, we not only preserve a beautiful and unique creature, but we protect resources that people need to survive.

Gharials are bizarre, but captivating reptiles. Their bulging eyes and noodley snouts make them look fantastical, and their unique lifestyles live up to their incredible appearance. Over millions of years of evolution, gharials have become integral to maintaining the health of their ecosystems, but they now struggle to survive due to the ways in which humans have changed both their habitats and the climate at large. By protecting this species, we can not only preserve their incredible beauty and sexy honking for years to come, but make life better for the many people with whom gharials share their river homes.


Image Credit: Ad031259 under CC BY-SA 2.0

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