Classification of Marshes

Marsh is a type of wetland that is continually flooded with water. Marshes can be found both on the coast or inland. Most of the water present is due to surface water; however, some groundwater also fills this wetland area.

Marshes can be divided into two main categories: non-tidal and tidal.

Non-tidal Marshes:

  • Most widely distributed and productive wetlands in North America
  • Occur along the boundaries of lakes, streams, rivers and ponds
  • Mostly freshwater, but some are brackish or alkaline
  • Beneath these wetlands lie highly organic soils
  • You might spot cattails, lily pads, reeds, and an array of waterfowl in this wetland
  • Alleviate flood damage and filter surface runoff

Tidal Marshes:

  • Found along protected coastlines and impacted by ocean tides
  • Present along the Gulf of Mexico
  • Some are freshwater or brackish, mostly saline
  • Provide shelter and nesting sites for migratory fowl
  • Covered by smooth cordgrass, spike grass, and salt meadow rush
  • Slow down shoreline erosion

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It’s Blue Crab Season – Let’s Get Crackin’

FUN FACTS:

  • Female blue crabs mate only once during their lifetime.
  • The average lifespan of a blue crab is 3 years.
  • The scientific name, Callinectes sapidus, means “savory beautiful swimmer.”

Blue crabs are crustaceans with a hard upper shell, typically grey, blue, or brownish-green in color. The blue crab gets its name from its sapphire-tinted claws. Blue crabs have two large claws, six walking legs, and two paddle-like swimming legs. One thing that sets male and female crabs apart is that females have red tips on their claws. Another distinction between male and female blue crabs is the shape of the abdomen. A blue crab male’s abdomen has a long, narrow, inverted “T” shape while females have a broader, rounded “U” shaped abdomen.

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Blue crabs spend the majority of their lifetime in estuaries which often have accessible shorelines, making blue crabs a delicious challenge to catch. Blue crabs are not only sought after by commercial fishermen but recreational crabbing has become rather popular as well.

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Louisiana’s blue crab fishery is the largest in the United States accounting for more than half of the total amount harvested in the Gulf of Mexico each year. Blue crabs are prized for their sweet, tender meat and are one of the most popular forms of seafood in the United States.

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Blue crabs tend to feed on oysters, mussels, snails, plant and animal detritus, and even smaller or soft-shelled blue crabs. These creatures are very sensitive to environmental changes and populations will drastically decline if habitats are disturbed. The blue crab relies heavily on healthy wetlands for survival and the sustainability of their population. The Coastal Wetlands Planning, Protection, and Restoration Act supports healthy estuaries that serve as habitat for species such as the blue crab.

 

Cheniere Ronquille Barrier Island Restoration

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This area is undergoing shoreline erosion, interior wetland
loss, overwash, and breakup. The Gulf shoreline erosion rate
has doubled from 1988 to 2006. Project area marshes also
are being eroded at -11.8 ft/yr between 2003 to 2006 as well
as being converted to open water from internal breakup.

Restoration would expand the Gulf shoreline structural
integrity and associated protection by tying into two recently
constructed projects to the east and address one of the
remaining reaches of the Barataria/Plaquemines shoreline.
The design includes fill for a beach and dune plus 20-years
of advanced maintenance fill, as well as fill for marsh
creation/nourishment. The location of the type and amount
of sediment needed to construct this project already has been
identified under the East Grand Terre Project that is presently
under construction. Approximately 127 acres of beach/dune
fill would be constructed and approximately 259 acres of
marsh creation/nourishment would be constructed. Intensive
dune plantings would be conducted by seeding and installing
approved nursery stock. About half of the
marsh platform would be planted with cordgrass and
portions of the dune, swale, and marsh would be planted
with appropriate woody species. Containment dikes would
be breached no later than year three to allow tidal exchange
with the created marsh.

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The project is located in Region 2, within the Barataria Basin
portion of Plaquemines Parish.

This project is on Project Priority List (PPL) 19.

The Cheniere Ronquille Barrier Island Restoration project sponsors include:

Keep up with this project and other CWPPRA projects on the project page.

 

Oysters for Coastal Restoration

More than a seafood delicacy, oysters are an incredible natural resource. They are extremely helpful to our environment by filtering water, providing habitat, and controlling erosion. Adult oysters may filter up to two and a half gallons of water per hour, which in turn improves water quality. Oysters build reefs that provide habitat for fish, shrimp, crabs, and other aquatic animals. Oyster larvae need the hard, shell surface for settlement and growth. A special focus that has been put on oysters recently is their ability to control land erosion.

Oyster reefs have been constructed along eroding shorelines in an effort to lessen wave energy and ultimately reduce erosion. Seven of our nation’s fifteen largest shipping ports are located along the Gulf of Mexico. The wakes created by the cargo ships heighten erosion along an already disappearing coastline.

Globally, it is estimated that 85% of oyster reefs have been lost. Large-scale restoration projects can create man-made oyster reefs that duplicate many of the benefits of natural reefs. Oysters and the massive reefs provide a foundation for a healthy ecosystem. The Coalition to Restore Coastal Louisiana (CRCL) founded the Oyster Shell Recycling Program in 2014. This program collects shells from New Orleans area restaurants and utilizes the shells to restore fading oyster reefs that protect Louisiana’s coastline.  A majority of shell removed from the coast is not returned back to the waters. It is vital to Louisiana’s disappearing coastline that oyster shells are brought back to help as a line of defense for coastal restoration.

 

Hypoxia

Hypoxia

Hypoxia is the lack of oxygen in the water column. In the Gulf of Mexico’s Texas-Louisiana Shelf, hypoxia is defined as seasonally low oxygen levels (less than 2 milligrams/liter). This Gulf of Mexico “dead zone” is caused by input of excess nutrient pollution, primarily nitrogen, to the gulf from the Mississippi River. Due to an overabundance of nutrients, excessive algal growth (eutrophication) may result and demand large quantities of oxygen which decreases both dissolved oxygen in the water and available aquatic habitat in the water column. The significant decrease in levels of dissolved oxygen in the water column results in the death of fish and shellfish and/or in their migration away from the hypoxic zone. The northern Gulf of Mexico adjacent to the Mississippi River is the site of the largest hypoxic zone in the United States (8.5 million acres) and the second largest hypoxic zone worldwide. Freshwater and sediment diversions from the Mississippi and Atchafalaya Rivers may help reduce the hypoxic zone off Louisiana’s coast by channeling nutrient-rich waters into coastal wetlands, where the nutrients can be used or trapped by marsh and aquatic vegetation.

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Cameron Meadows Marsh Creation and Terracing

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Significant marsh loss in the Cameron Meadows area is attributed to rapid fluid and gas extraction beginning in 1931, as well as Hurricane Rita and Ike. Rapid fluid and gas extraction resulted in a surface down warping along distinguished geologic fault lines. During the hurricanes of 2005 and 2008, the physical removal of the marsh coupled with subsequent low rainfall has resulted in the conversion of intermediate to brackish marsh to approximately 7,000 acres of open water. In addition to these losses, significant marsh loss has resulted from saltwater intrusion and hydrologic changes associated with storm damages.

The goal of the project is to restore approximately 400 acres of coastal marsh habitat and reduce the fetch by constructing approximately 12,150 linear feet of earthen terraces. Sediment will be hydraulically dredged from the Gulf of Mexico and pumped via pipeline to create approximately 380 acres of marsh (295 acres confined disposal and 85 acres unconfined disposal). Funds are included to plant approximately 180 acres. Approximately 12,150 linear feet of earthen terraces will be constructed in a sinusoidal layout to reduce fetch and wind-generated wave erosion. Terraces will be constructed to +3.0 feet NAVD88, 15 feet crown width, and planted. Terrace acreage will result in four acres of marsh above Mean Low Water.

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The Cameron Meadows Marsh Creation and Terracing project is located in Region 4, Calcasieu/Sabine Basin in Cameron Parish, approximately five miles northeast of Johnson Bayou and five miles north of the Gulf of Mexico.

This project is on Priority Project List (PPL) 22. The 30% Design Review meeting was completed July 2015 and the 95% Design Review was completed in October 2016. In January 2017, the CWPPRA Task Force approved CS-66 for Phase II Construction.

The Cameron Meadows Marsh Creation and Terracing project sponsors include:

Keep up with this project and other CWPPRA projects on the project page.

Wetland Nurseries

Did you know:

Wetlands provide a critical nursery for many of the Gulf of Mexico commercial fishery species.

One of the most significant fishery industries in the lower 48 states is the Gulf Coast fishery. Louisiana wetlands, particularly coastal marshes, play an imperative role in the life cycle of about 90% of Gulf marine species such as oysters, blue crabs, and shrimp. Providing a protective nursery, wetlands house an immensely diverse quantity of species that rely upon this habitat such as blue crabs, menhaden, and redfish. The Coastal Wetlands Planning, Protection, and Restoration Act aims to continue the protection and restoration, and health of these essential habitats for wildlife, aquaculture, and fisheries.

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