A Wing and a Prayer
Could coastal restoration bring waterfowl back to the Maurepas Swamp?
For Warren Coco, 1997 is a year that will forever be etched in his memory. That’s when common salvinia, an invasive aquatic plant, began to infiltrate Maurepas Swamp at such a lightning pace that by the next year the wetland was radically altered.
“The salvinia took everything, everywhere,” said Coco, owner of Go-Devil Manufacturers of Louisiana; the company, which produces boats and their motors, is headquartered in Baton Rouge.
Salvinia could have hitch-hiked via boats or traveled with high tides to the cypress-tupelo swamp, which is west of Lake Pontchartrain and south of Lake Maurepas. Once established, the plant blankets the surface of water, smothering out native vegetation and creating hypoxic conditions. It all but eradicated native aquatic plants like duckweed, which once covered Maurepas, said Coco; during winter, those plants could attract thousands of waterfowl—mostly mallards, gadwall and widgeon. “It was the best place I’ve ever duck hunted in Louisiana, hands down,” said Coco.
There are no historical waterfowl population figures that can accurately portray how many ducks wintered around the swamp, most of it now owned by the Louisiana Department of Wildlife and Fisheries as Maurepas Swamp Wildlife Management Area (WMA). The only relevant data dates back to 2006, available from the LDWF’s self-clearing permits, which hunters fill out before and after each hunt on WMAs. These permits give the department an idea of how many animals were harvested and when. Last season’s permits portray how poor the hunting has been recently—in almost 600 hunter efforts in the WMA, only 270 waterfowl were harvested.
The only evidence of Maurepas’s heyday comes from anecdotal accounts shared by hunters like Coco and the videos and photographs they captured. Not long after Coco first ventured in the swamp in the early ‘80s, he boasted to Phil Robertson, founder of the duck call factory Duck Commander, about the superb hunting in the swamp. In 1986, Coco hosted him on a memorable hunt in Maurepas.
“Robertson called, and he killed one,” said Coco. “Then I killed one. Then, another group would come in. We killed a five-duck limit in about fifteen minutes. He said, ‘This is unbelievable. We need to make a video here.’”
Over the course of two hunting seasons, Coco brought Robertson and a small film crew to his duck holes deep in the swamp, recording footage that was later compiled into The Duckmen of Louisiana, the first in a series of videos that eventually helped catapult the Robertson family to fame via the wildly popular A&E series, Duck Dynasty.
Barely a decade later, in 1998, Coco said he had hardly killed a duck in the same blinds he and Robertson hunted in. Since the beneficial aquatic vegetation had vanished, the flocks of waterfowl opted for more fertile ground. Coco hasn’t hunted the area in almost twenty years now. On his last venture into Maurepas, a few years ago, he said the landscape was hardly recognizable—scores of trees had died and the blanket of salvinia was seemingly endless, making the boggy swamp appear like solid ground.
“That was the prettiest swamp I had ever been in—I just fell in love with it,” said Coco. “But then the salvinia got everything, and the hunting died.”
The swamp, too, has been dying for decades, but the salvinia seemed to deliver a fatal blow. The first assault began in the late nineteenth and early twentieth centuries when the virgin cypress forest was clear cut—old growth trees, many of them as wide as cars and more than 1,000 years old, were leveled. Levees lining the Mississippi River starved the swamp of fresh water and sediment, while spoil banks from canals have held in stagnant water for decades. Saltwater intrusion from Lake Pontchartrain has killed scores of trees and turned those areas into open water.
While healthy swamps go through periods of dryness and wetness that allow cypress seeds to germinate, most of the Maurepas is wet year-round, which means most of the trees are around eighty years old—having come up since the last time the area was logged, with few new or older trees around. Erik Johnson, Director of Bird Conservation for Audubon Louisiana, said that migrating waterfowl and other birds won’t find an ideal habitat there.
“That habitat is one-dimensional and that system is not very sustainable,” he explained.
New Life for the Swamp
In 2017, the Coastal Protection and Restoration Authority (CPRA) received a $14.2 million grant to design, engineer, and seek permits for the
$200 million Maurepas Swamp diversion project. Outlined in the state’s 50-year, $50-billion coastal master plan to halt coastal erosion, the project aims to breathe new life into nearly 45,000 acres of the swamp. Construction could begin in 2021 and will take three to four years, said Brad Miller, project manager with the CPRA. The idea is to create a structure in the levee near Garyville that can be opened and closed, designed to bring mostly fresh water and minimal sediment to the area.
“The diversion will help with water fluctuations to provide opportunities for seedlings to actually germinate, so you can create a more dynamic forest with old and young trees,” said Johnson. “It’ll improve the flushing of stagnant water, promoting the growth of submerged aquatic vegetation and other emergent wetland vegetation that provides food for a base of animals.”
Gary Shaffer, professor of biological sciences at Southeastern Louisiana University, noted that it’s difficult to predict exactly how the diversion will impact the swamp. “This has never been done in the world,” said Shaffer, who specializes in wetland restoration. “Louisiana is the first to restore swamps. Until it happens, we can’t measure the benefits.”
But Shaffer does have an idea of how the swamp might react, thanks to a similar project he worked on near Lac des Allemands. In 2011, he designed a plan to restore that wetland, which, like Maurepas, also had stunted tree growth and oxygen-deprived water trapped by levees. The plan evolved into the “Hydrological Restoration and Vegetation Plantings in the Des Allemandes Swamp” project, and in February 2018, holes were carved into levees around the swamp to let the stagnant water out, allowing the area not only to dry up, but also to receive freshwater and nutrients delivered by tidal exchange. Shaffer and his team have monitored the area before- and post- construction.
“When the swamp got drained, the trees started pushing seeds,” he said. “You wouldn’t think they would behave this fast, but they jumped. They converted tissue from wood and leaves to seeds because they got the opportunity for a regenerative event.”
The Maurepas Diversion’s floodwater will pass underneath I-10 with a capacity of 2,000 cubic feet of water per second. Shaffer would rather see closer to 25,000 cfus. Near Sorrento, the proposed Union Freshwater Diversion is slated to have 75,000 cfus, which will also impact the Maurepas Swamp.
“That’ll benefit the entire Pontchartrain Basin,” he said.
Even still, said Shaffer, that 2,000 cfus for the Maurepas Diversion will greatly impact the swamp; he believes researchers will notice a rapid improvement in its health. Within the first year, measurable changes should be present as trees drop seeds and seedlings begin to sprout. Then will come larger trees and increased canopy closure. At Des Allemands, said Shaffer, there was a canopy closure increase of twenty percent in only one year.
While the new vegetative growth could help attract ducks back to Maurepas, said Johnson, that’s not the goal of the diversion, and it’s unclear how much it will impact waterfowl migration. There’s also still the matter of the salvinia, which could outcompete any new growth from plants like duckweed. Though, according to Johnson, a denser canopy could shade out some light and stunt salvinia growth.
“The only thing you can count on in duck hunting is change. Nothing stays the same. I hunted the mouth of the Mississippi River, Hackberry, Maurepas—I’ve seen change everywhere.”
Darin Lee, a coastal resource scientist with the CPRA who duck hunted Maurepas Swamp in the late ‘70s and early ‘80s, agrees that canopy closure could help with salvinia in isolated pockets of the area.
“You might see some of the area return to species that can tolerate more shaded conditions, and these noxious species like salvinia might be reduced,” he said. “Although that’s a limited area that could be impacted.”
It’s safe to say the diversion won’t get rid of salvinia, which is difficult to control, let alone eradicate it. The LDWF uses herbicides to knock back salvinia within the WMA, as well as the salvinia weevil, a bug that eats the plant but is susceptible to frosts, limiting its effectiveness. For now, those methods have done little to curb the salvinia problem in Maurepas.
It’s unclear how the ducks could make a comeback in the swamp with salvinia having such a stronghold there. Coco knows this, and he’s long been in favor of a more ambitious plan.
“I’d go buy the biggest excavator marsh buggy and dig a levee around the swamp and then dry it out,” he said. “I’d get rid of all the salvinia, put water back in it and get ducks in there again.”
Coco knows his restoration plan will never get approved due to mitigation permit fees outlined by the Clean Water Act, which are necessary anytime wetlands are altered. He said it would simply be too expensive to complete the project.
He’s not holding out hope that the hunting will be exactly as it once was in Maurepas. The swamp has likely changed too drastically. For Coco, that’s part of waterfowl hunting, an inherently adaptive sport—ducks’ migration patterns change as weather systems shift, ecosystems change, or food sources dry up. “The only thing you can count on in duck hunting is change,” he said. “Nothing stays the same. I hunted the mouth of the Mississippi River, Hackberry, Maurepas—I’ve seen change everywhere.”
Coco has a lanyard to hold his duck calls, which he hangs around his neck while he hunts. He’s adorned it with metal bands that were once attached to ducks’ legs; scientists use these tools for population and migration monitoring purposes. For Coco, the hard-to-find bands are treasures from his past that bring to mind balmy mornings spent in the duck blind with friends. Most of all, though, they’re memories of Maurepas—of the old houseboat, the endless mats of duckweed that fed the waterfowl, and mallards diving through the cypress.
“I’m looking at my lanyard right now and I’ve got about 64 bands on there,” said Coco. “I guarantee you that 45 to 50 of them I shot in those woods in Maurepas.”