The North Carolina Wildlife Resources Commission coordinated with the U.S. Army Corps of Engineers and other partners on a project to restore an important waterbird nesting island near Cape Lookout National Seashore.
For decades, disposed dredge material has been piled up and formed small islands along North Carolina’s coast, and birds began to realize that these islands were a great place for them to nest. John Policarpo, a physical scientist with the Corps of Engineers, said Sandbag Island is one of these dredged material islands.
“They call it Sandbag Island because the island was actually ringed by sandbags, its, they use that, the sandbags, to contain the material, the dredge material, and build the island up above the waterline.”
Policarpo said Sandbag Island has endured intense levels of erosion over time, causing the island to shrink to less than one-tenth of an acre last winter.
“It had basically eroded to, um, practically nothing. It was just a little mound of sand above the water line.”
Policarpo said they have photos of pelicans standing wing-to-wing on the small plot of sand. At this point, the Corps already had plans to dredge the channel that runs from Harkers Island to the ocean, but where were they going to put the dredged material? Andrea Currylow, a biologist with the Corps, said the start of this project wasn’t dissimilar from most.
“The background idea wasn't to create bird habitat, it was to clear the channel. And that's what a lot of our projects are, is to maintain navigability of those channels.”
Moving forward in the project, the Corps partnered with N.C. Wildlife Resources Commission (NCWRC) and agreed they would deposit the dredged materials on Sandbag Island. Biologist with NCWRC, Carmen Johnson, said the project created a mutually beneficial scenario, where they could maintain the channel’s navigability and restore nesting habitat for birds.
“So we could have hundreds if not thousands of nests on this island,”
“These two little tufts of grass are about all that was left of the original island prior to the Corps restoring it.”
Out on Sandbag Island, the gradient of shelly sand mimics a moonscape with nothing but the wind and the slow lul of waves, where migrating birds come to rest on their long journey. Johnson said the island attracts American oystercatchers, brown pelicans, herring gulls, and hopefully Least Terns. Some of these birds need the shelly, quiet beaches for their scraping nests.
“One of their little scrapes, some of them can be as small as basically it looks like you tapped your toe in the sand. And for a Least Tern, which might nest out here, their eggs can be about the size of my thumb. And so having that shelly material, it just helps them camouflage their nests.
Johnson said these birds often prefer the same kind of sandy beaches that humans do, so these dredged islands are a vital habitat.
“These dredge material islands provide another area for the birds to use, where they can be protected and they have minimal disturbance from people and pets coming out, so they can nest each spring and summer.”
N.C. Wildlife Resources Commission and the Corps worked on giving the island the optimal slope for nesting birds. Since the project finished in April, the signs of success have been obvious
“Almost as soon as the work was completed on the island and the contractor would move their equipment within just a few days, we found two pairs of oystercatchers that had already moved in and they began to establish territory and they laid nests.”
As the team continues to monitor the island, they anticipate to see more birds as migration season begins.
“So we anticipate that next year we're going to see even more species come in and nest and use the island.”
Currylow said this was one of the first projects she worked on with the Corps, but she hopes to implement similar habitat-building strategies in the future.
“If we can start to use that material in, in beneficial ways like this, but if there’s other things we can do, other types of material that we can use to come up with some creative solutions, um, we can, we can build a lot of different types of habitat and keep that material that would have been taken out. We can keep it in the system and let it naturally go through processes.”
As coastal development continues to intensify, dredged material islands are becoming increasingly vital for waterbirds. By creating and maintaining these habitats, conservationists are helping to safeguard the future of these bird populations.