Wild, Wild Wetlands
Texas marshes, home to a stunning array of wildlife, have been drained, dredged and carved up, but now an unlikely team is working to reverse the decline.
By Wendee Holtcamp
The moon is full, the night is warm, and I’m sitting in the high seat of an airboat, like a queen on a wetland wildlife safari. I feel like a firsthand witness to the springtime creation of new life. The deep glunk-glunk of a bronze frog, like a banjo, creates the song of the night, and baby marsh birds are everywhere. Two black-necked stilts guide their chicks, beige fuzzballs on stick legs, across a mudflat. A 6-foot gator slithers perilously near as a downy moorhen chick submerges itself, and I gaze in awe at the glowing orange eyes of what seems like a hundred of the reptilian beasts down the watery slough.
It is so beautiful and wild that this could be Africa’s Okavanga Delta, only we’re a mere hundred miles east of Houston.
I’ve joined Texas Parks and Wildlife Department biologists at the 24,250-acre J.D. Murphree Wildlife Management Area to find and catch alligators and mottled ducks in the marshes on the upper Texas coast. Duck hunters converge on these marshes every fall and winter, but populations of mottled ducks have taken a nosedive in Texas over the past 45 years. Some blame the increase in alligator populations, but it’s more likely that mottled duck declines may merely be symptomatic of landscape modification writ large on this low-lying coastal plain formed from the Sabine and Neches rivers.
Since European settlers first arrived, this marshy landscape has been carved, dredged, polluted and sucked dry. Many different types of wetlands exist in Texas and around the world — from coastal marsh to prairie potholes to bottomland hardwood forests along creeks and rivers — and this is by no means the only place that wetlands have been disregarded in the pursuit of human enterprise before recognition of their intrinsic worth. For decades after European colonization, wetlands were maligned, feared and cursed, and according to the U.S. Fish and Wildlife Service, more than half of the lower 48’s original 221 million acres of wetlands have, in fact, disappeared. The U.S. Swamp Lands Act of 1849 gave away 65 million acres of federal wetlands with the caveat that the new owners would drain them.
Over time, attitudes changed. Science revealed the myriad ways wetlands help us — they provide critical habitat for the fish we harvest and the birds we delightedly watch, not to mention amphibians, reptiles, insects and other invertebrates. Coastal wetlands offer a measure of flood control by absorbing excess rainfall and protecting inland homes from greater destruction during hurricanes.
In the natural state of affairs, coastal wetlands exist in a gradient of saltiness. Farthest inland are freshwater wetlands, followed by intermediate, then brackish and, finally, salt marsh nearest to the ocean. Each type has its own unique plants and animals. Roseate spoonbills, pelicans, sandpipers, terns and other shorebirds feed on the abundant fish and shellfish in the estuaries, which include brackish, intermediate and salt marsh.
“[Almost] all the fish in the Gulf have their nursery habitat in the estuary,” says Tom Tremblay with the Bureau of Economic Geology, who has documented the loss of Texas coastal wetlands over the past 50 years. “If you lose the estuary, you lose the fish. That’s the bottom of the food chain for a lot of things.”
Freshwater marshes have the highest plant species biodiversity, and many shorebirds and waterfowl nest here.
“Freshwater coastal marsh is extremely important due to the diversity and production dynamics of fish, wildlife and plants found there,” explains Jim Sutherlin, TPWD’s upper Texas coast wetland ecosystem project leader, based at Murphree. “Here is where a tremendous amount of insect production occurs — dragonflies, mayflies and a host of others. This really cranks the food web.”
As the airboat picks up speed, bugs whiz by my face with surprising rapidity: whack-whack-whack. Above the water’s surface, cordgrass intermingles with blackrush and bulrush, sedges and common reed, creating a soft, windswept look. The bright spotlight illuminates wigeongrass beds growing under the water’s surface. Mottled and other “dabbling ducks” tip their bottoms in the air while feeding on wigeongrass and other underwater plants, along with the occasional crayfish and invertebrate.
From the water, the marsh looks vigorously healthy and abounding with new life. In the cover of night, hens take their brood out to feed and explore, and seeing these wild animals in their natural element is breathtaking. Yet, from a bird’s-eye view, it becomes apparent how much the intricate labyrinth of marshy land has been carved up and dredged.
Starting in the late 1800s, engineers began building the 1,050-mile Gulf Intracoastal Waterway parallel to the coastline, and it now stretches from Brownsville to Florida. The intracoastal waterway, the Sabine-Neches Waterway (which cuts a path from north to south) and other smaller inlets, canals and ports have permanently altered the natural hydrology, or water flow, across the coastal plain. Coastal freshwater and intermediate marshes are particularly vulnerable because once channels are cut, that allows tidal water to move much farther inland than it ever had before.
“Too much salt water will kill freshwater plants that hold the fragile organic soils together,” says TPWD biologist Mike Rezsutek. “Once the plants are dead, the soil is easily eroded, turning marsh into open water. More-salt-tolerant plants can’t colonize before the soil is lost.”
Most baby marsh birds do not like salty water, either. Ducklings of mottled ducks, for example, will die in water with salinity over 8 parts per thousand.
Much of Texas’ coastal wetlands have disappeared or been negatively affected since human settlement, and nowhere is that loss more pronounced than on the upper Texas coast. This region nearest Louisiana loses more than 40 feet of land per year — the highest rate of coastal erosion in Texas and some of the highest in the nation — compared to a statewide average of two feet per year. Sea level is rising around the world, but the “relative sea level rise” varies on different coastlines. On the upper Texas coast, not only is the ocean level rising, but the ground is also sinking because of the extraction of groundwater and oil. All this contributes to the decline of coastal marsh.
We glide through the watery labyrinth as the full moon ascends, a giant orb over the landscape owned by the gators and ducks, frogs and fish. As we approach a family of mottled ducks, Rezsutek lies on his stomach at the airboat’s bow, ready to catch each and every one as they scurry for cover.
He hands them to another biologist, who counts each one out loud before placing it into a sack. After the entire brood is captured, each duckling gets a leg band and is released. The data collected helps provide information on movements, survival, harvest rates and population estimates. Another team is out catching alligators to document their abundance and diet.
The shimmering lights of the Beaumont–Port Arthur petrochemical complex, one of the nation’s largest, illuminate the horizon. In these modern times, wild nature overlaps human enterprise. On the Texas coast, they are intertwined, interspersed and, to some extent, interdependent. And after decades of conflicting interests and demands on the landscape, in a few shining examples, they have begun to work together not just to make up for damage done, but as partners in the creation of new life.
Six years later, I’m on an airboat in the same coastal marsh but in broad daylight, when ducklings, baby birds and most gators are hiding. Sutherlin takes me out to a cracked, drying moonscape of brown mud in the middle of the Murphree’s Salt Bayou Unit. The vastness of the mud field is astounding. It stretches on as far as the eye can see.
Did all those hurricanes wash the marsh away? Did it die from salty water? Did it erode or sink from rising seas? What happened here? The mud, it turns out, is part of a project to reverse the decline of the marsh.
With so much coastal marsh eroding and degrading for various reasons, biologist Jamie Schubert in TPWD’s Coastal Fisheries Division submitted a post-Ike recovery grant application to the National Oceanic and Atmospheric Administration, and was awarded $1 million to restore 37.5 acres of marsh.
“We were able to bring Golden Pass Liquid Natural Gas on board and use their dredged material to leverage the funds and increase the project size to about 1,500 acres,” says Rezsutek. In the Sabine-Neches Waterway, Golden Pass ships unload in a terminal that is equivalent to a driveway off a street. Mud constantly fills in and settles on the bottom of the terminal, requiring constant dredging. Instead of dumping it at a Corps of Engineers dredge placement site, Golden Pass opted to work with TPWD to create a beneficial use for the dredge spoil.
The airboat pilot kills the engine, and we carefully step out and onto a giant expanse of cracked mud. “It’s like the surface of the moon,” says Sutherlin. It’s barren, all right. I have to walk carefully on the solid surfaces, which are separated like pillars with masses of goopy muck in between and underneath — after all, they deposited 3.2 million cubic yards of mud here.
Building up the elevation of the marsh buffers it against erosion and sea level rise, which has contributed to marsh decline here for decades.
“Settlement will occur across the entire area,” explains Rezsutek, “so the end product will have similar contours — ponds, channels, high marsh — as the degrading marsh, just at a slightly higher elevation.”
All the mud gets tested to make sure it does not have any chemicals that could be toxic to wildlife or plants. When it’s ready, the mud is transported from the terminal to the marsh through a giant pipe, and then workers allow the mud to settle before planting three different marsh grass species. Sutherlin points out the rows of newly planted salt grass, marsh hay and seashore paspalum.
“We have to re-establish vegetation on the landscape to get the habitat to function,” he says.
Within a few months, this entire area will be covered in verdant marsh grasses — along with feeding shorebirds.
“Historically, this was fresh to intermediate marsh. Changes to the hydrology cut off freshwater flows, and the Sabine-Neches Waterway allowed salt to come in a big way,” says Sutherlin.
Right now the restored mud marsh is brackish, but as a mosaic of emergent plants gets re-established over time, it should become less salty. TPWD has plans to reduce the volume of salt water that reaches the marsh here, and then over time, the region’s notoriously heavy rainfalls will help keep fresh water in the marsh.
“Our intent is to restore the hydrology to a point where we simulate the historic functions of that landscape,” Sutherlin says.
The project exemplifies how TPWD can work with industry to create win-win situations. Besides Golden Pass’ terminal, there are billions of cubic yards of dredge spoil that comes out of these channels every year, some of which is now used in various “beneficial use” projects around Texas bays and estuaries.
“We can complain about the navigation folks all we want to, but when we start to solve this is when we start working with them to use every ounce, every cubic foot of this material that comes out of the ship channel,” says Sutherlin.
“I think that we are growing as professionals as a result of things like Hurricane Ike that just devastate the whole system,” Sutherlin adds. “It allows us to really begin to build our vision for how the Texas coast might be maintained.”