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A State of Emergency

---Part 1 of a 6-Part Series---

On May 15, 2000, Greg Linscombe, a wildlife ecologist with the Louisiana Department of Wildlife and Fisheries (LDWF), noticed something curious during his helicopter survey of so-called "nutria eat-outs" along the state's coast.

While the troublesome, marsh-devouring rodents leave behind signature trails and grazed areas that indicate their presence and relative abundance, Linscombe was encountering something entirely new. He had seen pockets of stressed smooth cordgrass (Spartina alterniflora) during his 30 years in the field, but he had never see the large, multiple tracts of browned areas he observed that day, tracts that looked more like the grass usually does during its winter dormancy rather that the vigorous greening more typical of spring.

Little did Linscombe know that the report he would share with fellow researchers after his Bell Jet Ranger touched down would be the first warning sign in what would prove to be a full-blown coastal crisis. Over the next several months, the "brown marsh phenomenon," as scientists in Louisiana dubbed the dieback, would explode into an unparalleled coastwide browning of Louisiana's intertidal smooth cordgrass that alarmed even the most seasoned coastal observers. And ever since Linscombe's report, scientists across Louisiana's gulf coast have sought to explain what amounts to a troubling ecological "whodunit."

Smooth cordgrass is the dominant marsh grass species constituting the seaward margin along North America's eastern and gulf coasts, in much the same way that mangroves do farther south. But more than simply the widespread death of a single plant species, the concern was over the fate of Louisiana's entire coast, a region that has already had enough trouble holding its own over the past century. During that period, the increasing number and height of levees designed to prevent the Mississippi River from flooding have continually decreased the amount of marsh-sustaining fresh water and sediment flowing into the neighboring wetlands.

At the same time, dredging of innumerable channels central to the oil and shipping industries has profoundly changed the interior hydrology, creating new avenues for salt water to penetrate inland. With the scales thus tipped towards ever-higher salinity levels, inland marsh species with lower salt-tolerances than smooth cordgrass-the most salt-tolerant of them all-often find themselves outside of their tolerance levels, especially at the edges of estuarine systems. When these plants die, the root systems that bind the submerged soil decay and collapse. As the soil surface drops, the substrate often lowers to the extent that no plant species is able to recolonize. Rendered vulnerable to wind and wave erosion, once functional wetlands soon convert into open water. And as the salt water encroaches ever inland, this destructive cycle plays itself out again and again.

Despite a decade's worth of successful mitigation efforts, Louisiana still suffers 25-35 square miles of coastal wetland loss each year. Hence, the challenge of suddenly facing a massive browning and dieback that extended farther inland was met with a great sense of urgency by both the state government and the coastal preservation community. For example, the Barataria-Terrebonne intertidal salt marshes, which alone cover some 390,000 acres, had 110,000 acres severely affected by the dieback. By year's end, 17,000 acres had converted from dense vegetation to open mud flats that were simply waiting to be washed away, and about 90,000 more acres seemed poised to meet the same fate.

"This is the first time the entire 'brain trust' of Louisiana's coastal science community has been brought to bear on a single project, and they realized at the outset that for this thing to work, cooperation and open lines of communication would be absolutely critical."

It was in the midst of this escalating climate of crisis, then, that the state seized the initiative. Coordinated through the U.S. Geological Survey's National Wetlands Research Center (NWRC) in Lafayette, researchers from several agencies and universities were surveying the situation from both the air and ground by early June, mere weeks after Linscombe's initial report had been filed. At the same time, Louisiana Governor Mike Foster directed his Executive Assistant for Coastal Activities, Len Bahr, to work the problem.

With emergency funding secured through the Governor's Office, the Louisiana Department of Natural Resources (LDNR), and the Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA), Bahr's office saw to it that a more thorough and fully quantitative helicopter survey was flown, a preliminary analysis of oceanographic data was drafted, and that high-resolution infrared photography of the region was acquired. As these and the USGS reports were beginning to come in, Bahr prepared memoranda for Governor Foster that summarized the situation to date, the need for an emergency proclamation, and the rationale behind the request for emergency congressional funding.

As per Governor Foster's order, the task of organizing these collaborative teams into a coherent research program was handled by the Barataria-Terrebonne National Estuary Program (BTNEP), one of the 20 National Estuary Program's regional centers across the nation. BTNEP's quasi-public status made it the ideal vehicle for such a challenge, coordinating, as it regularly does, with universities, private industry, and a host of government agencies at the national, state, and local levels.

By mid-January, a two day conference held in Baton Rouge brought together hundreds of investigators from across a broad spectrum of disciplines, including hydrology, climatology, biology, ecology, chemistry, wildlife management, economics, and remote sensing. The researchers came prepared to talk about what had been learned from the preliminary investigations, and, more ominously, how little certainty existed concerning the dieback's spread, the chances for recovery, what the next growing season might bring, and-almost unthinkable-what the results would be if a hurricane were to hit. In addition to Governor Foster's attendance, the gravity of the problem was underscored by the presence of Dr. Charles Groat, the Director of the U.S. Geological Survey, and Dr. Donald F. Boesch, the president of University of Maryland's Center for Environmental Sciences.

As an outgrowth of Governor Foster's executive order, the BTNEP framework, and the free exchange of ideas facilitated by the conference, a comprehensive "Brown Marsh Project" study team was formed. The project, it turned out, would be every bit as unprecedented in the field of gulf coast science as the brown marsh phenomenon it was undertaking. Because the effort was composed of 32 "tasks" and led by 64 principal investigators drawn from 17 institutions and private entities, coordinating the project's work flow, ensuring a common nomenclature among the disparate disciplines, and constructing a transparent database for a wide variety of computer-based analytical tools was a daunting challenge in and of itself.

Beyond the question of coordinating the massive effort, however, was the question of funding. Instrumental in this regard was Louisiana Congressman Billy Tauzin. Tauzin spearheaded the authorization of $3 million in emergency funding within the National Oceanic and Atmospheric Administration (NOAA) budget, part of the larger Department of Commerce appropriations bill. The bill passed in the waning days of the 106th Congress and was signed into law by President Bill Clinton on December 21, 2000.

With the final framework and the requisite funding mechanisms squarely in place, the Brown Marsh Project was officially underway. Within the project were four broadly defined subprojects in which the 32 individual tasks would be classified. The tasks within the "Data Management and Synthesis" subproject were central to the success of the overall project because it was within this area that the mountains of datasets generated by the other 31 tasks would be housed and accessed. In addition to archiving the on-going data generated by observation and experimentation, the projected impacts of the dieback on plants, animals, and human socioeconomic activities were included in the Data Management and Synthesis subproject as well.

An aerial view of the brown marsh phenomenon, including healthy green marsh, distressed tracts and open mud flats. Over 100,000 acres in coastal Louisiana were similarly affected.

Another subproject was "Status and Trends," the combination of imaging-based efforts and ground-level assessments aimed at identifying and mapping brown marsh so that the investigators would have a comprehensive picture of the situation with which to begin. A third subproject was the investigation of "Causes."

Perhaps the central, "$64,000 question" that the Brown Marsh Project aimed to answer, the search for causes looked at numerous environmental stressors in the field, in laboratories, and in greenhouses: salinity levels, hydrology, soil biogeochemistry, and "climatic drivers" such as rainfall and sustained high temperatures.

The fourth and final subproject was "Remediation," the array of field and laboratory studies that examined ways in which the stressed plants and barren tracts could be nurtured back to health via strategies that included sediment deposition, aerial reseeding, and vegetative plantings.

Aside from the science itself, perhaps the two aspects of the Brown Marsh Project that have most surprised the investigators are just how smoothly the effort has integrated different scientific disciplines and-when compared to the usual pace of scientific data gathering, analysis, and reporting-the blistering speed with which the project has moved. According to Len Bahr, "This is the first time the entire 'brain trust' of Louisiana's coastal science community has been brought to bear on a single project, and they realized at the outset that for this thing to work, cooperation and open lines of communication would be critical."

But even given the commitment to work in a large, integrated effort, the Governor's Office, along with the project's participants, were pleasantly surprised at the speed at which the project has proceeded. As Paul Kemp, a coastal geologist with Louisiana State University (LSU), puts it, "When the brown marsh first appeared, it revealed our fundamental lack of knowledge regarding the role of the water balance in the larger ecological setting of the Louisiana coastal zone. But what we've seen over the last several months is nothing less than science moving at warp speed to answer this question in a comprehensive way."