A marine life researcher recently made a shocking discovery on a beach in Texas. According to a video posted to YouTube, Jace Tunnell of the University of Texas Marine Institute found a 4-foot-long sea creature on a beach on Mustang Island. Tunnell identified the creature as an especially large American eel. The video was posted as part of an educational series on the Mission-Aransas National Estuarine Research Reserve YouTube page.

“If you’ve never seen one of these before, [you should know] this one is larger than normal. This is basically as big as they get,” he says in the video. “This thing is massive…Usually, they’re a lot smaller. People use them for fishing bait and stuff like that. Of course, this one is too big for that.”

What is an American eel?

American eels are widespread but considered rare in the Lone Star State. According to Texas Parks & Wildlife, “the American eel has a slender snakelike body with very small scales, and the fish may appear naked… It probably spans a wider range of latitudes than any other species in North America. American eels occur as far west as New Mexico and are common throughout the Caribbean and the West Indies. Although it is native to much of Texas, the construction of dams, which impede upstream spawning migrations, has eliminated this species from most central and western areas of the state.”

Because of its large size, Tunnell says the eel specimen he found is likely a female. According to the U.S. Fish and Wildlife Service, American eels are the only species of freshwater eel in North America. The agency goes on to clarify that they are technically considered “catadromous, meaning they primarily live in rivers and estuaries, but migrate out to the ocean to spawn.”

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Female eels are known to lay up to 4 million eggs at a time. After spawning offshore, they often die. The species is distinct from the commonly-known moray eel. The cause of death of the eel that washed ashore on Mustang Island is not clear.