Alligator Gar: The Gator Fish

It swims like a fish but has elongated jaws with sharp teeth that are visible when it opens its mouth, similar to an alligator or a crocodile. So is it a fish? Or is it an alligator? I am not sure who had named this fish which has been scientifically described in 1803, but it has been given a common English name to match its characteristics. The fish is named Alligator Gar.
The fish is generally olive green or yellow and has a heavily scaled body. A tooth-filled mouth and wide, alligator-like snout give the species its name. With a prehistoric look, the Alligator Gar is one of the largest freshwater fish. Its name is derived from the alligator-like appearance of these teeth along with its elongated snout, and is indeed the largest freshwater fish in North America. A mature Alligator Gar fish can grow up to 10 feet and can weigh over 90 kilograms. It has been one of the largest and toughest fish, and the alligator gar is a favourite target of anglers who love this particular sport of fishing.
The alligator gar has a streamlined body to facilitate swimming and its dorsal and anal fins are located very far back on the body. Gars’ bodies are covered by ganoid scales, which are thick overlapping scales that create a protective covering similar to medieval chainmail – like those worn by heroes of favourite movies such as Robin Hood or Gladiators.

The river giant
These menacing-looking fish are indeed prehistoric. Scientists track the gar’s tenure on earth back to 150 million years to about the time birds began to fly. Although fossils of gars have been found in North America, Central America, Europe and Asia, the living members of the family are restricted to seven species living in North and Central America.
The Mississippi River in North America is recorded to be the alligator gar’s main hideout. They can live in fresh and brackish water bodies. The fish, despite its giant size, is relatively passive and prefers to live a solitary life. Alligator gar can also breathe air directly which allows them to survive even in murky waters. According to some literature, there are records of alligator gar having lived on land, and that is something people find surprising. They have been known to survive on land for a period of up to two hours. They may be on land to look for food or to escape from predators.

Predatory fish
Alligator gar is a carnivore fish as anybody can guess by seeing their sharp teeth. Alligator gars have two rows of teeth. The inner row of teeth is palatine and is longer than the outer row of teeth which gives them a good bite of their prey. The teeth of the alligator gar are long, slender, and fang like, giving them a good bite of their prey. They have ambush techniques in hunting prey, feeding by lurking amongst reeds and other vegetation. They like staying hidden and launch their attack on the unwary prey, and generally the prey doesn’t even know the gar is present until it is too late. They lie still in the water until an unsuspecting fish swims by, and then lunge forward and lash the head from side to side in order to capture the prey. Many times gars will lie still at the top of the water for long periods of time, appearing like a log.
Alligator gars prey on fish but they are opportunistic and have been known to feed on everything from waterfowl and small turtles to carrion. Alligator gars have been reported to attack duck decoys and eat injured waterfowl shot by hunters.
There are also speculations that larger alligator gar attack humans. But there has been no confirmation of such attacks. Though they wouldn’t attack human, their eggs, if ingested, are poisonous to humans.

Popular aquarium fish
All the Gar species are popular aquarium fish and quite interestingly the alligator gar is one of the most popular. But they are quite demanding, needing clean water as well as lots of space as they grow. In the Dehiwala Zoo the alligator gar has a moderately spacious tank. The tank has been enriched with suitable habitat to the alligator gars with some decayed logs and large stones placed within. Alligator gar like such hiding places.
Records show that there are seven gar species in the world. The alligator gar is the largest. Of the seven known gar species, the alligator is the largest and the heaviest. They weigh around 300 pounds (140 kilograms) according to records.
The breeding habits of alligator gar still remain largely unknown, but it is believed that they spawn on flood plains that expand towards the river ecosystems. Alligator gars are thought to spawn in the spring by congregating in large numbers with a female and one or more males on either side to fertilize the eggs. Web resources indicate that females generally carry an average of 138,000 eggs. The eggs are released and fertilized by the male outside of the body. They sink to the bottom after being released and stick to the substrate due to an adhesive outer covering. The eggs are bright red and poisonous if eaten. Alligator gars are thought to spawn in the floodplain of these large rivers mainly to give their young protection from predators.
They grow slowly and take a long time to mature. Females mature at 11 years and live up to 50 years. Males mature at six years and live to at least 26 years.

Conservation
The alligator gar is disappearing from many parts of the range, and declining in population everywhere due to over-fishing and the construction of dikes, dams, and other flood control mechanisms resulting in loss of key breeding habitats. The alligator gar was once reported as common and even numerous in much of its northern range. Now it is rare in the northern parts of its range with reports of valid sightings coming in once every few years.

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