Though the fin-clipping technique has been shown to work for other fishes, no one had ever tried it with alligator gar. “We need to understand their biology and their ecology, but you don’t want to sacrifice a fish that’s that old or that grows so slowly,” says Hogan, who is also a National Geographic Explorer. (Read about Hogan’s quest to find the world’s biggest fishes.)
Some alligator gars live to be 95 years or more, Hogan says, making each individual precious.
“I found the results the paper very promising,” says Zeb Hogan, a research biologist at the University of Nevada, Reno, who was not involved in the study. We can see how that fish might be changing with its growth.” “Let’s say we catch the same fish a month or two later, or maybe a year later. “It also allows us to sample organisms repeatedly,” says David, who notes the fins grow back quickly. There’s no way around it.”įortunately, in their new study, Fredrickson and David have just proven that fin clipping is much easier on the gar. However, because gar have scales like medieval chain mail, the time-consuming and traumatic practice of extracting that amount of tissue can cause stress on the animal, says Thea Fredrickson, an aquatic biologist with the Lower Colorado River Authority in Texas. To do that, they’d normally need to take a nickel-size sample of the fish’s tissue, which contains traces of elements scientists can use to track the fish’s whereabouts. To protect gar, scientists first need to know basic information, such as where the behemoths roam and what they’re eating. “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. The alligator gar is a snaggle-toothed fish longer than a park bench and heavier than a mountain lion.
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