Fall in Gulf of Mexico estuaries bring a curious visitor to its saltwater habitats. As the water begins to cool, gulf sturgeon migrate from their summertime rivers to saltwater feeding grounds. These animals that have been around for 65 million years, about as long as our modern sharks, tell a story about water as they travel between habitats.
Gulf sturgeon are native in the Gulf of Mexico from the nature coast of Florida to Louisiana, and make their way up the Suwannee River into Georgia during summer. Sturgeon will travel to the river where they were born to spawn, a location called the “natal river.” Salmon that swim upriver to breed are returning to their natal rivers, while female sea turtles will go back to their natal beaches to lay eggs.
Once they’ve spawned, sturgeons will spend fall, winter, and early spring in saltwater habitats. These bottom-feeders act like a vacuum and suck up invertebrates, small fish, and can even suck polychaete worms from their burrows. Their mouth, located on the underside of their skull, is a toothless vacuum that swallows prey whole.
Sturgeon as long as 12 feet have been documented, but they typically reach about 6 feet in length. They borrow anatomy from other aquatic creatures in a curious combination. Instead of scales, these fish have bony plates similar to alligators and gar. Sturgeon also share a cartilaginous spine like that of sharks, and even have barbels like catfish.
Unfortunately, most sturgeon larvae don’t survive due to predation, disease, or water level changes like flooding or drought. This naturally low survival rate paired with their slow breeding makes them especially sensitive to human threats. While hunting has been abolished, dams prevent sturgeon from migrating to their natal rivers. Dredging projects destroy eggs and release sediment that suffocates them while removing the sturgeon’s bottom-dwelling food sources. Poor water quality and bycatch are secondary threats to sturgeon populations.
Due to their heavy-duty build and large size, breaching sturgeon have been known to cause injury to boaters. If you’re on the water in sturgeon habitat, keep an eye out for these prehistoric marvels, and look before they leap! You can read more about gulf sturgeon and their close relatives, Atlantic sturgeon, through this Florida Fish and Wildlife Conservation Commission website.