For thousands of years, Alabama sturgeon fought their way from the Gulf of Mexico up the Alabama River to breed each spring, the resulting eggs tumbling down hundreds of miles of free-flowing water, developing along the way into tiny sturgeon that would someday make the pilgrimage themselves. Today, two dams built more than five decades ago and sixty miles apart on the Alabama—separating it from its tributary the Cahaba River in the Appalachian foothills above—block that journey, and no Alabama sturgeon have been caught since 2004.
But now Jason Throneberry, an Arkansas native and the director of freshwater programs for the Nature Conservancy in Alabama for the past six years, is fighting to restore the ancient migratory pathway for the sturgeon and countless other fish species, from eels to Alabama shad to mullet. “With these dams in place, the system functions more like a lake,” Throneberry explains. “The water moves so slowly that sediment deposits on the bottom, limiting the diversity of habitat.”
That carries a heavy price; the Alabama River system is one of the most biodiverse on the planet, with hundreds of fish and mussel species found nowhere else. Between 1982 and 2002, sampling surveys indicated a decline of up to 40 percent in the diversity of fish species, a measure that has only plummeted further since. “We’ve reached the critical period,” Throneberry says. “We are going to start seeing the fish and other aquatic organisms that should be here blinking out.”
Late last year, Throneberry led TNC into a partnership with the U.S. Army Corps of Engineers to gather data and hatch a plan for circumventing the dams—each will most likely have either a bypass channel or a rock arch for fish passage. The endeavor will take years, so in the meantime, Throneberry and his team are working to manage stormwater and restore stream banks along the Cahaba to control sedimentation there. “Once the fish can get around those dams,” he says, “we want the habitat to be ready to rock and roll.”
The reconnection effort has been on TNC’s radar for well over a decade. “But it took Jason, with the combination of his scientific expertise and get-it-done attitude, to make it happen,” says Mitchell Reid, TNC’s Alabama state director. “Restoring the connection in this system, from the Appalachian foothills to the Delta to the Gulf, is the most ecologically important river project we’ve undertaken in North America.”