CRMS-Wetlands:
A New Approach to Wetlands Monitoring

Data collected through CRMS-Wetlands will provide ecologists with a better understanding of how natural and human processes interact in each of Louisiana’s coastal habitat types.
Louisiana Department of Natural Resources

Nearly a decade ago, the CWPPRA monitoring program began to develop a new monitoring strategy. This new strategy, known as the Coast-wide Reference Monitoring System-Wetlands (CRMS-Wetlands), was developed to assess the cumulative effects of all the coastal projects by establishing a network of reference sites across the coast. It was also designed to provide information needed to ensure current and future efforts would work at recreating a sustainable coastal ecosystem.

The CRMS-Wetlands approach was developed by DNR in collaboration with scientists at USGS, University of Louisiana at Lafayette and Louisiana State University. A key strategy is to establish a reference standard, or target, as a goal for restoration projects. Planners also seek to better understand the variability in the environment and the collective effectiveness of the entire restoration program.

Selecting Sites

Developing a comprehensive monitoring program across 3.67 million acres of coastal wetlands is a daunting task. The interplay of geology, biology, hydrology and possible climate change results in a highly variable and dynamic system that is complicated even further by human impacts (construction of canals and levees, for example). One major challenge was to determine how many monitoring stations were necessary to cost-effectively assess this complex landscape.

A team of ecologists and statisticians, working with historic data on coast-wide salinity and vegetation, determined it would take 700 sampling stations to install an effective and robust monitoring program. Central to this plan were the coast-wide vegetation surveys conducted by Robert Chabreck of LSU and Greg Linscombe, Louisiana Department of Wildlife and Fisheries. Using their transects (sample areas in a continuous strip) as a starting point, the CRMS-Wetlands system of sampling stations was expanded to cover habitats representing swamp, bottomland hardwood, and fresh, intermediate, brackish and saline marsh. Sites along these transects were randomly selected within each habitat classification as CRMS-Wetlands stations.

This design offered added values in that many of the selected stations represent a 35-year history of vegetation change, and that the transects on which the design was based have been used by LDWF not only for vegetation surveys, but also for alligator, nutria, muskrat and water bird surveys. The monitoring variables that will be collected, combined with LDWF, Corps of Engineers and USGS coast-wide datasets, will provide information on vegetated wetlands and the habitats they support. This flexible design will allow resource managers to better understand ecological change, from the project scale to the entire coast; they will also be able to compare the effects of a specific type of restoration effort—diverting fresh water or sediment, for example—in a certain basin, or across the coast. The plan is to have monitoring equipment installed and people in place to begin collecting data under CRMS-Wetlands early in 2005.

Because coastal Louisiana is such a complex and dynamic system, the application of a particular technique is likely to produce results that vary depending on the project location. “A significant improvement in the CRMS-Wetlands design,” says USGS ecologist Greg Steyer, “is that it will allow us to better understand the influence of each project type at specific locations in the landscape.” This understanding will in turn aid in the site selection and engineering of future restoration projects.

CRMS-Wetlands monitoring will help scientists better understand the causes and impacts of periodic events such as the “brown marsh” phenomenon of 2000. The aerial view of Bay Junop in June 2000 shows the first stage of the die-off; in less than 10 months, affected areas had deteriorated to mud flats.
USGS/NWRC

Like the monitoring conducted to date, CRMS-Wetlands will monitor such critical variables as water level, salinity, sedimentation, elevation and the variety and abundance of vegetative species within a site. Data will also be gathered on land-to-water ratios to evaluate how the landscape is changing. CRMS-Wetlands data will be assessed to test hypotheses of how these variables interact to support healthy and sustainable wetlands, and further the understanding of vegetation and landscape dynamics.

All of these data will be collected at each site and provide a snapshot to allow comparison with all other sites. “One of the benefits of CRMS-Wetlands,” says Rick Raynie, monitoring program manager with DNR, “is that each site will have the same suite of variables, giving us the flexibility to aggregate stations in a variety of ways to answer many different questions. We’ll have more flexibility to answer questions relative to individual projects as well as collective effects at much larger scales.” The data will also provide clues into understanding how the coastal environment is changing. Scientists will be able to map each site’s “trajectory”—where it is headed in terms of health and stability.

Something for Everyone

CWPPRA has evolved over the years to meet changing needs. The Coast 2050 initiative, developed under CWPPRA in 1998, provided long-term habitat goals and strategies. This was the start of coastal restoration in Louisiana at the ecosystem scale. Because CWPPRA has recognized that small-scale projects will not completely remedy a large-scale problem, more effort has been placed into ecosystem-scale planning. With this evolution of scope came a parallel evolution in monitoring: from small-scale, project-specific to ecosystem-scale for the entire coast.

During the last few years, several events have impacted coastal Louisiana that scientists would better understand today had CRMS-Wetlands been in place. Examples include the “brown marsh” phenomenon that killed thousands of acres of coastal Louisiana salt marshes in 2000, and Tropical Storm Isidore and Hurricane Lili in 2002. Data from CRMS-Wetlands will contribute to the body of knowledge so that scientists can better evaluate and understand such periodic events.

CRMS-Wetlands will also help in developing simulation models for coastal Louisiana that predict environmental reactions of the landscape to various management alternatives. Up to now, modelers made assumptions based on their best professional judgment because of limited data on wetland hydrology and ecology. CRMS-Wetlands will provide much of the data to validate and fine-tune these models so that predictions of future impacts will be more accurate. CRMS-Wetlands will also provide information to CWPPRA planners and project designers in areas of the coast where currently no information exists, and should help identify areas needing restoration and expedite the design and construction of future projects.

What’s Ahead

It is increasingly clear that monitoring serves more purposes than project evaluation alone. The evolution of the CWPPRA monitoring program from the project specific scale to CRMS-Wetlands will benefit project planners, designers and resource managers. The new monitoring capabilities offered by CRMS-Wetlands will allow scientists and coastal experts to better understand the problems that Louisiana’s coastal wetlands face, and determine which types of solutions are the most effective. The data collected will lead to more accurate projections about how these invaluable habitats will change in the coming years, and aid in the evaluation of progress toward meeting the specific objectives of Coast 2050.

To facilitate the ongoing feedback of information and the evaluation of cumulative project effects, the CWPPRA monitoring program is also providing information in increasingly user-friendly formats. Raw data are available on the Web (www.saveLAwetlands.org; www.nwrc.usgs.gov), as are all of the project-specific and programmatic monitoring reports. Beginning later this year, annual project-specific operation, maintenance and monitoring reports will combine monitoring data with other information for a holistic view of project performance and effectiveness. In addition, these reports will be merged into a hydrologic basin-level report that will evaluate the collective effectiveness of all of the projects within each basin. This information will provide insight to resource managers evaluating ecosystem-scale problems and CWPPRA’s solutions to them.

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