Wednesday, July 31, 2013

Louisiana's Disappearing Islands

By: Alan Raymond
Published: July 31,2013
 
 
 
 
 
A string of uninhabited islands in the Gulf of Mexico have gone from teeming with wildlife to nearly non-existent thanks to constant pummeling from tropical systems, and according to some scientists, climate change is making matters far worse.
Restoration efforts on the books to save the Chandeleur Islands, a 50-mile trail of atolls just off the coast of Louisiana, and home to the Brenton National Wildlife Refuge, may be too little, too late.

Part of a $320 million settlement has been designated to help restore parts of North Breton Island, according to the Federal Register, which tracks all federal environmental action. The money comes from $1 billion set aside by BP to compensate for damages to natural resources in wake of the Gulf oil spill. But no firm timetable has been set for the project.
The restoration project won’t be enough to save the entire chain, said Neil Lalonde, wildlife refuge manager with the National Fish and Wildlife Services. The islands’ degradation from continued storm surge could lead major implications to southeast Louisiana, he said.
Climate change will also add to the crisis, said Dr. John Lopez, executive director of the Lake Pontchartrain Basin Foundation, a group dedicated to restoring and preserving the water quality, coast and natural habitats of the region.
"The loss of the islands is part of a natural process of delta barrier island evolution that may well be accelerated due to more frequent storms resulting from climate change," Lopez said. "The loss of the islands is a tragedy that can be averted."

Jewel of the Natural World

The islands are the remnants of an abandoned Mississippi River delta and are a haven for millions of marine animals for more than 2,500 years. In 1904 President Theodore Roosevelt, after learning of the destruction of bird habitats, designated the chain a wildlife refuge.
Breton is an extremely rich estuary system that is important to wading, sea and shore birds, migratory waterfowl and songbirds, crab, shrimp and saltwater fish, Lalonde said. The refuge also provides critical habitat for large colonies of nesting seabirds, including brown pelicans, laughing gulls and terns.
During the last 15 years unprecedented erosion, due to constant pummeling from tropical systems, have left the barrier islands clinging to existence and its wildlife seeking other habitats, Lalonde said.

What Hurricanes Have Done

Although the sands around the Chandeleur Islands have been shifting for centuries, the last 25 years have seen them virtually eliminated. Their demise isn't from direct human interaction. Mother Nature has torn the islands to shreds with numerous hits from hurricanes.
“Every passing hurricane takes a toll on the islands,” Lalonde said. “Without any major restoration projects the islands are in imminent danger of disappearing.”
In 1998, Hurricane Georges damaged the ecosystem and the physical structure of the land. Georges also lead to a 2001 multimillion dollar restoration project. Native flora was replanted in hopes of helping the Chandeleur Islands retain sediments for the next big hurricane.
But that work was in vain as Hurricane Ivan, a Category 3 behemoth that made landfall near Pensacola, Fla. in 2004, once again damaged the islands.
Since Ivan, the Chandeleur Islands have weathered at least six hurricanes. The most notorious was 2005's Hurricane Katrina.
Historically, Breton National Wildlife Refuge, including the Chandeleur Islands, was about 11,000 acres, according to Lalonde. The refuge was about 1,100 acres in 1998, before Hurricane Georges. It was down to 500 acres in 2005 after Hurricane Katrina, Lelonde said.
Katrina, one of the country’s deadliest and most destructive hurricanes, roared over the islands with Category 3 strength winds. According to a Texas A&M study, there is some evidence that the loss of coastal barriers made the Hurricane Katrina storm surge worse, leading to the flooding of New Orleans in August 2005.
The islands took a beating from Katrina’s strong winds and massive waves, some higher than a two-story house, razed an iconic lighthouse built in 1896 and washed away the majority of Chandeluer's land masses, leaving them in desperate need of repair.
That renourishment, natural or otherwise, never came as hurricanes Rita in 2005, Gustav in 2008 and Ike, also in 2008, laid claim to the islands, each taking chunks of an ecosystem as they left.
In 2010, sand berms were built to protect parts of the archipelago from oil spewing from the Deepwater Horizon disaster, a 2012 USGS report said. A $360 million settlement from BP paid for the sand berms, which were built by the state of Louisiana. However, in a post-Hurricane Isaac coastal survey from a USGS team revealed that the sand berms virtually obliterated.
While the islands were overrun with water in 2012, they were still intact and offered some amount protection to the mainland.
But as each progressive storm passes, it takes massive chunks of the islands. At the current rate, these invaluable islands could be long gone within a generation, Lalonde said, leaving the fragile Louisiana coast even more vulnerable.

Chandeleur Islands Battered By Katrina

Chandeleur Islands Battered By Katrina
NASA
NASA images of the Chandeleur Islands before (left) and after (right) taking a hit from Hurricane Katrina, in 2005.
  • Chandeleur Islands Battered By Katrina
  • Sequential Comparison of the Chandeleur Islands, 2001-2005
  • Chandeleur Islands Comparisons
  • Chandeleur Islands Comparisons
  • Chandeleur Islands Comparisons in 2012
  • Chandeleur Islands Comparisons
 

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