![]() “These are river giants.” Fin clips, for the win “Just the sheer size of these animals blows you away when you're in their presence,” David says. In a January study in the journal Transactions of the American Fisheries Society, David and colleagues showed that instead of cutting into the fish’s flesh to gather samples, taking small clips of fin can provide the same information. That’s why David and his colleagues are trying to reverse the fish's decline, for instance by breeding them in captivity and devising ways to learn more about the creatures without harming them. What might be of ‘least concern’ globally is definitely not the case on the local scale,” says David. states such as Texas and Louisiana- which is why they’re listed as of least concern by IUCN. Alligator gar, found as far south as Central America, are more common in the southern parts of their range, especially in U.S. ![]() In some states, such as Ohio and Illinois, the species has disappeared completely and is considered locally extinct or extirpated. They called it the Electrical Gar Destroyer.Ĭombine those direct threats with habitat loss due to dam construction and floodplain draining, and alligator gar are now extremely rare in the upper river systems of America where they were once common. In the 1930s, the Texas Game and Fish Commission even built a boat that discharged electric volts into the water. (Learn more about freshwater fish.)īut their role as top hunter has earned alligator gar a bad reputation with anglers and even state wildlife managers, who sometimes tried to exterminate the animals, thinking they were competitors to game fish. The freshwater species keep prey populations in check by hunting smaller fish, amphibians, reptiles, mammals, and birds, David says. “They have to swallow their prey whole, so they’re harmless to humans.”Īlligator gar, which can weigh more than 300 pounds, are like their namesake in one way: They’re apex predators, which means they provide critical ecosystem services to their home habitats-which is mostly the middle and lower Mississippi River watershed in the U.S. Many don’t realize that the 10-foot-long alligator gar still exists, but when they do, their first thoughts often turn to fear, says Solomon David, a fish ecologist at Nicholls State University in Louisiana.īut “they’re not like alligators, lions or other animals that can tear off pieces of prey,” says David. Bony scales covering its body make it look like an armored dinosaur, and for good reason: North America’s second-biggest fish has been thriving since the late Jurassic period, 157 million years ago. Go to the external links below for more information.The alligator gar is a snaggle-toothed fish longer than a park bench and heavier than a mountain lion. Some scientists have hypothesized that the complex heart structure of crocodilians might indicate that they evolved from endothermic (warm-blooded) ancestors. This increased mixing helps crocodilians transition to a lower metabolic state, and enables them to dive for extended periods. Crocodilians also have a valve in the pulmonary artery that, when closed, forces deoxygenated blood to recirculate through the left aorta, which increases mixing. Crocodilians have evolved a shunt between the left and right aorta (immediately above the ventricles) to facilitate the mixing of oxygenated and deoxygenated blood. The single ventricle of the 3-chambered reptile heart allows some mixing of oxygenated blood with deoxygenated blood, which may help regulate their metabolic state. ![]() The advantage of a 4-chambered heart is that oxygenated blood and deoxygenated blood are separated, which results in more efficient respiration needed for the high metabolism of endothermic (warm-blooded) animals, and enables different pulmonary (lung) and systemic blood pressures, but is seemly over-complex for ectothermic (cold-blooded) crocodilians. While most reptiles have 3-chambered hearts, the heart of alligators, and all crocodilians, has 4 chambers, a trait shared with mammals and birds. Florida Youth Conservation Centers Network.Great Florida Birding and Wildlife Trail. ![]() ![]()
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