In January of this year, high water on the lower Mississippi River prompted the U.S. Army Corps of Engineers to open of the Bonnet Carré Spillway for the 11th time in its 85-year history. The Bonnet Carré Spillway doesn’t just help lower water levels pressing against the flood protection levees, it’s also a thriving wilderness area that benefits from the periodic opening of the spillway structure and the sediment and fresh water it brings.
Despite initial concerns from redfish and speckled trout anglers when the spill way was opened, the additional sediment and water did not push fish from Lake Pontchartrain. Anglers had successful runs throughout the spillway’s opening, as the fish enjoyed the brackish environment the lake offered. By understanding the history of this structure and the mechanics of its operation, we can better understand the implications of the introduction of river water and sediment into nearby fish and wildlife habitat.
Built in the aftermath of the devastating 1927 flood, urgency saw this 350-bay structure designed and built in just two and a half years. When the Mississippi River above New Orleans is in flood, this floodway can divert up to 250,000 cubic feet of water per second and sometimes more. That’s enough water to fill almost 3 Olympic size swimming pools every second. The water flows from the Mississippi River across the spillway and into Lake Pontchartrain.
When the spillway is opened, water and some sediment is pulled off the top of the river and a portion of this sediment is deposited within the spillway. Fresh water also leaks through the timbers of the structure into the spillway when the river stage reaches more than 15 ft. This periodic introduction of fresh water, sediment and nutrients simulates the natural flooding of the river that once built and help maintain much of southeast Louisiana before levees were constructed. Sediment deposition in the spillway can be seen in sediment cores and with the presence of natural cypress regeneration – a rare sight in most swamps in the region.
Since the spillway only pulls water off the top of the river, and there is typically less sediment at the surface than there is at deeper depths, less sediment moves through the spillway compared to water. This makes the Bonnet Carré different from the planned sediment diversion projects which will be located, designed and operated to maximize sediment capture. However, the periodic introduction of fresh water and some sediment benefits the habitats of the spillway, including bottomland hardwood forest, grasslands, ponds and cypress swamps. The productive habitats of the spillway support an abundance of wildlife, including gray squirrels, whitetail deer, swamp rabbits, alligators, wood ducks, mottled ducks, crawfish and a wide-range of finfish. With more than 7,600 acres of public lands, the Bonnet Carré Spillway provides opportunities for fishing, hunting, camping, boating, cycling, horseback riding, ATV riding, and many other recreational activities.
Alisha Renfro is the staff scientist for the National Wildlife Federation’s (NWF) Mississippi River Delta Restoration program. Based in New Orleans, she provides accurate scientific information to help advocate for the best coastal restoration projects for Louisiana. She also helps translate scientific information for the Mississippi River Delta Restoration Campaign’s public outreach and communication efforts.
By Brittany Boyke, Habitat Restoration Program Coordinator, Coalition to Restore Coastal Louisiana
Saturday, April 2nd was the culmination of a two-year effort to rebuild one of Louisiana’s once mighty coastal forests.
The Coalition to Restore Coastal Louisiana’s Habitat Restoration Program in partnership with the Restore the Earth Foundation (REF), Lake Pontchartrain Basin Foundation (LPBF), the Coastal Protection and Restoration Authority (CPRA) and 46 volunteers planted the final 1,165 trees in the Caernarvon Diversion Outfall in St. Bernard Parish, reaching the goal of planting 10,000 trees in the area.
The 10,000 trees initiative began in the fall of 2014 and set out to restore 80 acres of coastal forest that were devastated by Hurricanes Katrina and Isaac. In all, 800 volunteers donated 6,400 hours of their time to help restore this vital natural buffer by planting tree species which included red swamp maple, bald cypress, blackgum and water tupelo.
The Caernarvon Freshwater Diversion Project Outfall Area is on the border of St. Bernard and Plaquemines Parishes, just south of New Orleans. This once beautiful coastal forest was deforested at the turn of the 20th century and due to more recent hurricanes and storms, major erosion has taken place. By planting these saplings with a protective, nutria shield we have seen a 77% survival rate, which means this coastal forest will once again help protect the area from future storm surge. It has the added benefit of restoring the area’s natural fish and wildlife habitat and creating new land in the process. This newly planted forest also benefits from the fresh water and sediment that is diverted from the Mississippi River through the Caernarvon Freshwater Diversion.
This is just the first step in restoring our coastal forests. CRCL, REF, LPBF and CPRA are committed to planting another 10,000 trees beginning in the fall of 2016.
Be on the lookout for great volunteer opportunities surrounding this and other important restoration projects.
You can get a full calendar of CRCL’s Habitat Restoration projects by visiting crcl.org.
Brittany Boyke coordinates the CRCL Habitat Restoration Program, including site selection, plant selection and volunteers. She has a BS in Natural Resource Ecology and Management with a Concentration in Wetland Ecology from LSU. She was born in Lafayette, Louisiana, but graduated from Pearland High School in Texas. She has lived primarily between the two states.
Our partners at Audubon Louisiana published a series of blog posts that we are cross-posting here. View the original blog post here.
As we mark the sixth anniversary of the BP oil spill this week – an event that significantly and negatively impacted Louisiana’s already disappearing barrier islands and the species that depend on them – we will examine the status of barrier island restoration. Over the coming days, we’ll publish a series of blog posts that detail what work has been done to restore Louisiana’s barrier islands, the importance of these islands to birds and humans alike, as well as Audubon Louisiana’s role before, during and after the restoration process to monitor and improve bird health on these islands and elsewhere.
Part 3: "Audubon Louisiana: A Steward of Birds through Coastal Restoration"
By Erik Johnson, Director of Bird Conservation, Audubon Louisiana, @AudubonErik
Audubon Louisiana is deeply involved in monitoring and improving the health of bird populations across the state. Nowhere is this more important than on barrier islands, which provide critical habitat for many bird species as we’ve detailed in previous blog posts.
The restoration of larger barrier islands closer to shore, like Whiskey Island, Scofield Island and many others, raises questions regarding the nesting success of seabirds, if one follows basic tenets of Island Biogeography Theory. An important question that Audubon Louisiana is seeking to understand is how many more fledglings are produced on a given island after restoration compared to before. It is possible that overall nesting success could decrease after restoration, because a larger (restored) island might support more predators, causing seabirds to be less successful. However, if there are more seabirds nesting on restored islands, might the total number of chicks fledged could still be a net increase? What do we do if not?
Audubon is monitoring beach-nesting birds on Grand Isle and the Caminada Headland to answer some of these questions for Least Terns and Wilson’s Plovers. After protecting certain nesting areas from human disturbance, in which volunteers play an important role in preventing, we track the nesting success of birds, and determine causes of failure, such as storm surge and various predators.
If restored barrier islands act as refuges and havens for predators, and not nesting seabirds, what can be done to enhance seabird nesting success? The removal of predators can be expensive, challenging and unsustainable. Electric and other kinds of exclosure fencing might be feasible in certain circumstances, but is also relatively expensive, and often requires regular maintenance. A more sustainable approach might instead be to place greater emphasis on the construction of smaller offshore islands, through dredge spoil or beneficial use, particularly where land-building processes exist (such as near diversions and naturally accreting deltas).
By no means, might I suggest to reduce the emphasis on larger barrier island restoration – this has an important role in the protection of other coastal habitats and coastal human communities. Surely, barrier islands with some predators are better than no barrier islands. Considering how to maximize the efficacy of barrier islands for nesting seabirds will require an island-by-island assessment, regular surveys, and adaptive management. Each of these islands are one hurricane away from losing their predators, so a well-constructed barrier island that withstands one or more storms, might suddenly produce more birds than were produced in many multiple years leading up to that. Most seabirds are long-lived, and their ability to live and nest on the edge of the Earth gives them a chance to wait for this once-in-a-lifetime event. They take the long-term view – not all that different than Louisiana’s 50-year, $50-billion coastal restoration plan.
If you would like more information on Audubon Louisiana's Coastal Stewardship Program or would like to volunteer with one of our programs, contact Erik Johnson, Director of Bird Conservation for Audubon Louisiana, at firstname.lastname@example.org. You can also sign up here to receive the latest news, updates and volunteer information from Audubon Louisiana.
By our partner, National Wildlife Federation. View the original post here.
Six years ago this week, the Deepwater Horizon oil rig exploded, killing 11 men and spewing millions of gallons of oil into the Gulf of Mexico for nearly three months. At the time, many representatives from the Restore the Mississippi River Delta Coalition were on the ground, cataloging the impacts to wildlife and the habitats of the Gulf of Mexico.
Six years later, we are still hard at work. Yesterday, National Wildlife Federation released a new, interactive report that looks at what the most recent science says about the impacts of the disaster, and how we can restore the Gulf.
Some of the impacts described in the report:
- In the first five years after the disaster, more than three-quarters of pregnant bottlenose dolphins in the oiled areas failed to give birth to a live calf.
- As many as 8.3 billion oysters were lost as a result of the oil spill and response effort. The dramatic reduction in oyster populations imperils the sustainability of the oyster fishery in the northern Gulf of Mexico.
- In 2010, the oil spill killed between two and five trillion larval fish.
- The fate of as much as 30 percent of the oil remains unknown to this day.
- Twenty percent of the adult female Kemp’s ridley sea turtles may have been killed during the disaster, possibly explaining the turtles’ low nest counts.
Today, we know more about the devastating impacts of oil than ever before — and we also know more about what we can do to restore the Gulf of Mexico. As a result of the various legal settlements with BP and the other oil companies, more than $16 billion dollars will ultimately be available for environmental restoration.
We need to make sure that this money is used wisely on projects that benefit the Gulf as a whole.
Coastal Louisiana and the wetlands around the Mississippi River Delta — which were already eroding at an alarming rate pre-spill — received the brunt of the oil that hit the coast. Some marshes and barrier islands still have remnants of BP oil, even six years later.
The money from the settlement means that the very areas that were so badly injured stand a chance to rebound— if we use the settlement money to fund comprehensive, science-based restoration.
This year, on the eve of the anniversary of the Deepwater Horizon explosion, staff from the Restore the Mississippi River Delta Coalition took a tour of Shell Island West, a barrier island restoration project in Louisiana funded by early Natural Resource Damage Assessment funds. This project will restore approximately 600 acres of beach, dune, and marsh habitat. It is part of the larger Barataria Basin Barrier Shoreline restoration project, which will rebuild the eroding barrier islands that separate the ecologically and economically important Barataria Bay estuary from the Gulf of Mexico.
Restoring estuaries like Barataria Bay are key to improving the health of the Gulf of Mexico. Barrier islands serve as a first line of defense, protecting coastal communities from hurricanes and tropical storms. They also form protected areas where freshwater from rivers can mix with the saltier waters of the Gulf, creating nursery areas for many species of wildlife. These protected areas contain a variety of habitats – such as marshes or oyster reefs – that are vital for many different species. Therefore, the Shell Island West project will benefit fish and wildlife that use the barrier island and its beach as well as the marsh on its protected side.
But sadly, in many cases, barrier islands like the Shell Island West are eroding rapidly, leaving both people and wildlife vulnerable.
For our long-term protection, we need to rebuild these critical barrier islands while restoring important habitats like wetlands through sediment diversions and marsh creation. Creating a more natural connection between the Mississippi River and Barataria Bay by building controlled sediment diversions will rebuild and restore wetlands — and it will make projects like the marsh creation and barrier island restoration at Shell Island West more sustainable in the long run.
FOR IMMEDIATE RELEASE
Emily Guidry Schatzel, National Wildlife Federation, 225.253.9781, email@example.com
Jacques Hebert, National Audubon Society, 504.264.6849, firstname.lastname@example.org
Elizabeth Van Cleve, Environmental Defense Fund, 202.553.2543, email@example.com
Rachel Guillory, Ocean Conservancy, 504.208.5816, firstname.lastname@example.org
Andrew Blejwas, The Nature Conservancy, 617.785.7047, email@example.com
OIL SPILL ANNIVERSARY SPOTLIGHTS OPPORTUNITY FOR LARGEST RESTORATION EFFORT IN AMERICAN HISTORY
(Washington, DC —April 20, 2016) Today marks the sixth anniversary of the Gulf oil disaster, which killed 11 men and began an oil spill that would dump more than 3.19 million barrels of oil into the Gulf of Mexico. Earlier this month, U.S. District Judge Carl Barbier finalized the historic $20.8 billion settlement with BP – the largest environmental settlement in U.S. history – for the massive damages caused by the spill.
Groups working on Gulf restoration, including: Environmental Defense Fund, the National Wildlife Federation, National Audubon Society, Ocean Conservancy and The Nature Conservancy, issued the following statement:
“The opportunity to begin the biggest environmental restoration effort in American history is now a groundbreaking reality for the Gulf, following the finalization of the settlement with BP.
“In the aftermath of the spill, elected officials, state and federal agencies and residents across the Gulf worked together as never before to ensure passage of the RESTORE Act to benefit the ecosystems and communities of the region.
“We are eager to continue this work with both state and federal leaders to quickly update the RESTORE Act Comprehensive Plan, and advance restoration work.
“Restoring the Gulf wholly and correctly — and sooner rather than later — means that we’re fast tracking the region’s resilience, and protecting the people, wildlife and jobs across the Gulf for the benefit of the entire nation.”
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