Restoration of a Maritime Forest Ridge and Marsh Habitats at Fourchon, LA  

 In early 2001, the Barataria-Terrebonne National Estuary Program and the Greater Lafourche Port Commission fostered a partnership with other organizations to reestablish a chenier ridge and associated coastal marsh habitats in south east Louisiana.  This partnership was born from a desire to further the knowledge and expand the focus of habitat restoration in coastal Louisiana from purely a vision that supported marsh restoration to one that encompassed other natural landscape features.  Louisiana’s unparalleled coastal wetland loss problem means dire consequences for many species of birds.  But of as equal importance or the distributary ridges and chenier ridges that too are being lost at an alarming rate.  These ridge habitats and associated wetlands are extremely important for millions of migrating Neotropical songbirds that cross the Gulf of Mexico in the spring each year on their way back to their breeding grounds in the eastern United States and Canada.  This is especially true when migrating birds encounter inclement weather over the gulf.  Exhausted birds, once reaching land, must feed and rest at the first land they encounter.  That first land in many cases, are these cheniers.  This project includes pumping earthen material via hydraulic dredge and placed in shallow open water to a height of plus four feet.  Constructed in phases, each of the three components when finished will mean the restoration of over 100 acres of chenier ridge/marsh habitat that will encompass some 12,000 linear feet in length by 400 feet in width.  The earthen material once dried will be shaped into a marsh platform at a plus 1.6 feet elevation and the crown of the ridge at a plus eight feet.  Both herbaceous grasses and woody plants that tolerate the harsh growing conditions of coastal Louisiana will be planted.  The woody plants that are to be used are those that are known to be important to Neotropical migrant songbirds.  Just recently identified as a sanctuary where no consumptive use is allowed, the area once finished will be one of the premier birding destinations in the State of Louisiana.  Boardwalks, foot bridges, observation platforms, signage, and an interpretive center will be constructed to promote avian tourism at the site.

 

 Currently, the Greater Lafourche Port Commission is in the process of reestablishing a maritime forest ridge in the vicinity of Bayous Cochon and Moreau just north of the port at Fourchon, LA. BTNEP is serving as a co-lead implementor of this project along with the Greater Lafourche Port Commission and is helping to coordinate discussions and on the ground planning and construction.  In addition BTNEP is providing funding for this project.

This project serves several purposes. First, it will help protect the mitigation areas to its south from the continual pounding of waves thereby helping preserve the existence of these newly developed mitigation sites. Second, it will serve as habitat not only for many fish and shellfish species but also for many neotropical migratory bird species and small furbearers. Third, it will provide for ecotourism opportunities once completed.

Recently, the Greater Lafourche Port Commission established the entire area north of the port as a sanctuary including the mitigation areas, the ridge, and fringe marsh, as well as the shallow open water and broken marsh habitats that exist further north. A number of project partners have now joined and support this project concept.  They include, the Gulf of Mexico Program, the Gulf of Mexico Foundation, the Department of Natural Resources, and the National Oceanic and Atmospheric Administration.

The project concept for reestablishing this maritime forest ridge and fringe marsh along Bayous Moreau and Cochon includes the construction of retaining dikes and the pumping of dredge sediments into the area.  The first two phases of this project are currently being constructed.  Ultimately six ridge segments will be constructed.  The ridge’s segments will each have a dimension of 1,000 feet in length, by 200 feet in width, and eight feet in height, sloping to a, 100-foot wide marsh fringe on each side for a total width of 400 feet.  Gaps of 50 feet will be constructed between these ridge segments to serve as tidal creeks that will enhance access of marine species.

During construction of the ridge it will be possible and desirable to establish different elevation gradients at predetermined sites, allowing for a vegetation gradient from woody species at higher elevations to low woody shrubs then subsequently marsh vegetation at lower elevations.  During construction of the ridge, swales and different inclines will be constructed.  Swales will serve as small freshwater ponds that are extremely important to many species of wildlife that will utilize this habitat.  Shallow inclines will provide for different ridge geometries that will support different wooded habitats and provide for shallow gradients from the highest point of the ridge to shallow open water areas that provide for inundated hard bottom habitat that is important to many species of shorebirds.

On the 100-foot fringe around the ridge segments, marsh grass will be planted on five-foot centers.  Along the tidal creeks that run between ridge segments, a mixture of black mangrove and marsh grass will be planted.  Once the salinities atop the ridge have moderated and compaction has slowed, the area would be planted with indigenous trees such as live oak, hackberry, and others.

The entire project will be completed over three phases.  The first and second phase, under construction now, will include development of the ridge and marsh fringe in the center and western edge of the project area and will support the planting of 30 acres of marsh around 30 acres of ridge.  When fully constructed, the coastal ridge will stretch for approximately 12,750 linear feet and approximately 60 acres of marsh will be created.  Phase three will likely be constructed within five years.

For more information, go to Gulfmex.org/crp/2006.html