Questions remain over recovery of one of Mississippi’s most imperiled, and iconic, native species

Those same historical records also place their known habitat as one stretching from the Mississippi River to as far south as Tampa Bay, in coastal Central Florida.  

But as the United States began to industrialize, leaving the 19th century and entering the 20th, both their numbers and habitat began to rapidly dissipate.

While the country entered the Gilded Age and its nascent upper class grew, demand for luxury foods such as caviar or various cuts of smoked fish grew along with it. In Mississippi and neighboring Gulf states, the primary fishery supporting that market was Gulf Sturgeon. 

By the time it was listed under the federal Endangered Species Act as ‘threatened’ – only a step below endangered – in 1991, its range was determined by officials to have shrunk to between the Mississippi River and the Suwannee River in west Florida, nearly 200 miles to the north of its previous southern boundary.  

Even in those remaining habitats, populations throughout were noticeably smaller.

“What happened is a lot of unsustainable harvest,” said Mike Andres, an assistant professor at USM's Estuarine and Movement Ecology Lab. “Out of the Pascagoula River in 1905 they harvested something like 24,000 pounds of Gulf Sturgeon, which is a number that I can’t comprehend based on what we see of them in the Pascagoula now.” 

“If that’s what previously healthy populations looked like, we have a long time to go before we get there.”

Andres, joined by another researcher and two groups of technicians, conducts various research into the species throughout its range in Mississippi – including both the Pearl and Pascagoula River systems, as well as the Mississippi Sound and some of the nearshore Gulf of Mexico. 

An anadromous fish, Gulf Sturgeon migrate between rivers and estuaries seasonally, moving upriver in the spring as temperatures rise to spawn, and downriver in the fall when temperatures begin to drop, seeking warm waters along the coast. 

It’s there, in the dozens of estuaries lining the Northern Gulf, where the prehistoric fish feeds as far as the barrier islands forming the outer edge of the Mississippi Sound, in search of mollusks, crab or shrimp. 

Evolving from close relatives in the Jurassic Period – roughly 200 million years ago – is one of the reasons the species is widely considered to be a living dinosaur.

Along the lower Pearl River, marking the border between Mississippi and Louisiana, it’s overcast and not yet hot when Mike Andres drops the first gill net of the day into the water.  

“It's in those current break, low velocity locations, as well as cooler temperature locations that they tend to congregate,” said Andres. 

“Usually, if we set in an area that has a number of fish slowly meandering in these locations, it's not really trying to set on them as they're returning or moving to different stretches of the river. It's more so just  taking advantage of their biology.”

But those sections of rivers are increasingly rare across North America, and in Mississippi, as a result of navigation projects like dredging out channels that greatly impact species like Gulf Sturgeon by drastically altering the flow of the river itself.

Combined with the construction of dams or other structural water control measures that block their paths further upstream, the species has largely been confined to only a few remaining habitats, disrupting a well-established migration pattern. 

Andres says the furthest he’s aware of any Gulf Sturgeon traveling up the Pearl River was one that, thanks to unusually high water levels, made it over the low-head dam near Belhaven Beach in Jackson several years ago, to the lower-mouth of the Ross Barnett Reservoir.

Construction of the Reservoir northeast of Jackson in the 1960's had an especially negative impact on Mississippi’s Gulf Sturgeon – among several other species and ecosystems throughout the Pearl River basin – even hundreds of miles downriver from its spillway in Rankin County. 

By holding, and then releasing, large amounts of water south, operation of the Reservoir raises the water table of the river rapidly, inundating its banks.

But when the flow is suddenly shut off, much like closing a faucet, the river falls just as quickly and banks are left more susceptible to collapsing or eroding, adding more sediment to the river and permanently altering the floodplain. 

Prior to its construction in 1962, Gulf Sturgeon within the Pearl River system were known to travel as far as the river’s headwaters, north of today’s 33,000 acre Reservoir, to spawn or seek shelter. 

Today there are no known spawning sites throughout the Pearl River basin, and only one on the Bouie River, a tributary to the Pascagoula River, that the lab located in 2023. 

Andres says part of their work is finding those spawning sites, in addition to identifying how and where the fish move through river systems, to help officials better protect them.

‘Like going back in time’

On the lower Pearl River, that work is done among some of the last remaining tracts of bottomland hardwood forest in the United States. 

No more than 20 river kilometers from the Mississippi Sound, this section of the Pearl is much wilder than those further north, near the Reservoir. Original growth forest of cypress, water oak and tupelo line either riverbank for miles, abundant with osprey and hawk nests in the canopies of bald, twisting branches.

It’s also here where some of the last recorded sightings of the critically endangered Ivory-billed Woodpecker have occurred – believed by some to be definitely or probably extinct. 

Mike Andres says it’s no coincidence that both species might be in the same stretch of the Pearl. Instead, it’s emblematic of the ecosystem, and its biodiversity, persisting. 

“The west side is beautiful salt marsh, and this section of the Pearl has so much excellent flood swamp. It’s absolutely beautiful,” said Andres. “It feels like going back in time.”

After the crew sets a 300-foot wide, 6 foot deep gill net across the river, it's only a matter of minutes before they pull it, and two sturgeon are on board, placed in a live well. 

From that point it's a bit of a race for the researchers, who are working against the clock with a notoriously sensitive species. 

“We put an external tag on them, usually on both pectoral fins so that we have a quick, easy mark to see if we've recaptured that fish in a given year. They usually only last about two years,” Andres said. 

“Then we insert a passive induced transponder tag that’s energized by a magnet and sends out a number. That mark stays on them ideally for their entire life, but at least 10 plus years from which we've had some of our recaptured data in our systems in the Pearl and the Pascagoula and other systems. Some of those marks have lasted up to 18 years.” 

Best known as PIT tags, the lab combines that data with acoustic transmitters that sound when a Gulf Sturgeon passes one of several receivers spread throughout their habitat in Mississippi. That system helps researchers better understand where and when sturgeon are migrating, or gathering. 

They also take genetic samples from fins to determine which population – down to the specific habitat or family – a given fish was spawned in. 

"Just because we capture fish out of the Pearl doesn't necessarily mean it was born in the Pearl. We see fish from the Pearl and Pascagoula hanging out together in both of the systems, and sometimes they migrate from even further.”

Despite their prehistoric appearance, Gulf Sturgeon are mostly subdued. But signs of stress quickly show up in the form of red marks on their underside when they roll over to conserve energy, a similar behavior seen in sharks called tonic immobility. 

That makes the task of surgically inserting the PIT tags somewhat easier for Paul Grammer, a senior research associate at the lab. 

Grammar and his team of technicians split the work with Andres’ team across two boats, heading further north and under the Interstate 10 bridge to a fork in the stream. The same technique to catch the fish is applied: laying a gill net across likely Gulf Sturgeon habitat and waiting only a few minutes before they catch.

On this trip upriver, Grammar and his crew of three technicians have five sturgeon at once. That makes the task of heading back downriver to a small beach and conducting the rounds of testing even more urgent. 

Waist deep in the shallows, Grammer is using a scalpel to cut through the tough underbelly of this trip’s largest Sturgeon, inserting a tracker deep inside its body cavity, and then sewing it up -- all while the fish is floating just above the surface.

“We’ll put external tags if needed, and the PIT tag is like the microchip that goes in household pets, kind of like each fish’s unique Social Security number,” said Grammer. “But if they get where they’re lethargic and have a lot of that red marking underneath, we try to hurry them through and get them released.” 

While he wraps up, research associate Kasea Price makes a concerning discovery: a wad of discarded fishing line found its way into the gills of one of the fish. Grammer drops what he’s doing to try and help, and after a few minutes of careful work it’s out. 

But the find serves as a reminder of just how at risk Gulf Sturgeon have been for decades – especially those living on the line of human settlement and imperiled habitat.

Dozens of days a year, Andres, Grammer and other employees of the lab make trips up and down river, catching, recording and releasing as many Gulf Sturgeon as they can. The idea is to form as large a base of knowledge as possible of their populations in Mississippi to better protect them. 

But environmental phenomena like natural disasters or interactions between the river and industry located along its banks will, of course, only continue. 

When Hurricane Katrina slammed into Louisiana and the Mississippi Coast in 2005, its storm surge inundated the lower Pearl River for months with salt water from the Gulf, throwing off the River’s balance and available oxygen for aquatic species.

In 2011, a now-shuttered paper mill located in Bogalusa, Louisiana released enough of a corrosive liquid used in the breaking down of wood fibers – known in the industry as ‘Black Liquor’ – to kill hundreds of thousands of fish in a surrounding 60-mile stretch of the Pearl. 

Nearby Gulf Sturgeon populations were decimated by both. 

And hundreds of miles upriver in Jackson, the Army Corps of Engineers and local residents remain at odds over flood control measures for the Capital City. 

Major flooding as recently as 2020 and 2022 displaced dozens of households and businesses, with the latter flood directly contributing to Jackson’s water crisis. 

But flood control measures already in place for decades, such as the weir near Belhaven Beach or dams controlling the flow from some of the Pearl’s many tributaries, have already played a large role in restricting the habitat and movement of Gulf Sturgeon for decades.

While the newest flood mitigation project is only in its planning stage, several proposals under Army Corps of Engineers consideration call for altering the Jackson section of the Pearl River again. In some cases, they recommend further widening and other channel improvements. In others, building another low head dam to create another lake just north of Interstate 20.

Officials have said the lake proposal would combine both flood mitigation and open up potential recreation opportunities, but environmental advocates have long opposed the ‘One Lake’ option, largely because of what they say is a likely negative impact on Gulf Sturgeon and other species. 

As part of the flood project’s process, the Corps partnered with the Rankin Hinds Flood and Drainage Control District – local sponsor and longtime promoter of numerous attempts at some form of lake development – to draft an environmental impact statement on multiple alternatives.

Their team of scientists concluded that Gulf Sturgeon were not likely to be harmed long term by that particular option, should it be constructed. But sedimentation modeling remains to be completed, and the entire document reviewed by the U.S. Fish and Wildlife service, before final approval. 

At a 2020 meeting in response to that year’s major flooding, sitting Jackson Mayor Chokwe Antar Lumumba said the imperative of flood control takes priority over certain conservation concerns, per reporting by Nick Judin of the Mississippi Free Press. 

“There's been a pretty strong case for One Lake made in the last week," says Lumumba. "It may not be the politically correct thing to say, but I care a lot more about [Jackson residents] than some sturgeon."

Situations such as these, where balancing the needs of communities in Jackson and those of an endangered species collide, have defined conservation since its beginning. 

But Mike Andres says it's part of what makes the work, especially in the case of species like Gulf Sturgeon, more important – even despite some of the challenges that come with actual recovery. 

“Part of the issue that many species on the Endangered Species Act have is that it’s great once they're listed, but then there's not a lot of federal funds that are put towards actually recovering the species,” said Andres. 

“Just because it gets listed doesn't mean that there's money immediately set aside to actually achieve the recovery goals for the species. But when that's happened, things like bald eagles, alligators, gray wolf – when money's put towards it, we've had a lot of success. It turns out if you fund it, we can start to resolve some of the issues.”