See Rare Video of a Giant Oarfish Swimming

Giant Oarfish usually live at a depth between 650 feet and 3000 feet, which means that people rarely get a chance to see them with their own eyes. But recently, workers from Chicago's Shedd Aquarium spotted two 15-foot-long oarfish swimming in shallow waters in the Sea of Cortes in Mexico.

Growing up to 50 feet long, oarfish are the longest bony fish alive, and, according to the Florida Museum of Natural History, "its common name arises from its highly compressed and elongated body or from the old belief that the fish moves through the water by 'rowing' itself with the pelvic fins." What might at first look like blood in the video above is actually the fish's distinctly colored dorsal fin, which ranges from pinkish to cardinal red and runs along the entire length of the fish. And thanks to its huge size and distinct shape, we probably have the oarfish to thank for sailors' tales about sea serpents.

The fact that these oarfish are in shallow water doesn't bode well for them, according to Smithsonian, which notes that "when oarfish end up in such shallow water it usually portends a bad end for the fish, as they don’t generally venture into that portion of the ocean unless they are injured or dying."