NEW ORLEANS (WVUE) - At the end of Baptiste Collette Bayou near the mouth of the Mississippi River, thousands of birds have unexpectedly congregated this summer on a brand new island.
Biologists with the Louisiana Department of Wildlife and Fisheries estimate 50,000 birds, mostly royal terns and black skimmers, are nesting on the island.
The figure does not include the thousands of weeks-old chicks.
“This is the most birds I’ve ever seen in one single place, and maybe cumulatively, in a lifetime,” said Jeff Corbino, an environmental specialist for the U.S. Army Corps of Engineers.
A couple years ago, what Corps has designated Gunn Island-- for a longtime Corps employee-- was open water.
Contractors sculpted the island from sand, dredged from the Mississippi to keep the river open to navigation, an estimated 3 1/2 million cubic yards of material.
"If you look at the standard size bed of a pickup, it holds about two cubic yards," Corbino said. "So, we've got about one-and-a-half-million pickup trucks of sand out here."
The Corps builds these nesting sites and marsh through what is called, "the beneficial use" of dredge material.
Over the last dozen years, that has included about 10,000 acres of marsh and islands in Louisiana's Birdsfoot Delta.
For island construction, designers aim to create nesting sites that fall into a 60-80 acre sweet spot, just large enough to attract large colonies but isolated.
"We can attract birds to it and at the same time keep predators off of it just for the sheer distance that they are from shore."
Nevertheless, their arrival in such large numbers weeks ago caught biologists by surprise.
“Likely what happened is they got flooded out early for Tropical Storm Cristobal and they all moved over here,” said Casey Wright, a biologist for the Louisiana Department of Wildlife and Fisheries.
Wright believes the birds most likely migrated from Breton Island several miles to the northeast.
More new real estate could be in the works since the Corps plans to dredge a 30-mile stretch of the river from Venice to the Gulf.
A $250 million project will deepen the river to 50 feet, an extra five feet of depth which industry groups believe will lure the next generation of giant container ships and larger bulk cargo vessels.
"If we didn't do this, we lose cargo to other ports where people can go deeper," Sean Duffy, Executive Director of the Big River Coalition.
Duffy said the expanded dredging work should begin in coming months.
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