Virginia’s coastline could see some of the country’s most dramatic impacts of sea level rise due to climate change. Warming temperatures also threaten many marine animals, and the birds that eat them.
On a recent morning in May, Virginia Tech biologist Sarah Karpanty and a team of researchers from the University of Virginia gathers up their gear and loads it into a boat.
“And it’s about 5:30 in the morning before sunrise, and we are going head out to Myrtle and Smith islands on the Eastern Shore of Virginia,” says Karpanty.
Donald Fraser drove the boat, and he manages the logistics for these bird counts. “It’s so beautiful. It’s probably one of the best kept secrets of Virginia,” Fraser says. “It’s amazing. I feel very lucky to be able to come out here and do what we do.”
He steers between marshes as we head to a very small island, called Myrtle. Like many of the barrier islands, this land is protected and closed to the general public.
“There’s nowhere else like it on the U.S. Atlantic Coast,” Karpanty says. “And very few places in the world, where you have approximately 100 kilometers of protected shoreline that is undeveloped.”
Karpanty has spent the past twenty years tracking shorebirds, including a species called rufa red knots (Calidris canutus rufa).
“Which just passes through in spring migration, and they’re heading up to the arctic to nest,” Karpanty says.
These birds are long distance marathon flyers. “A red knot for example flies 19,000 miles round trip every year,” Karpanty explains. “Between their wintering grounds at the southern tip of South America and their nesting grounds in the high Canadian Arctic.”
It’s believed that a third of all red knots stop in Virginia’s Eastern Shore to feast on clams and mussels. Most of them arrive in mid to late May.
“When the red knots come in from migration, they have flown, likely, thousands of miles straight,” says Karpanty. “They may have flown for days and they are emaciated.”
They spend nearly 24 hours a day eating while they are in Virginia.
“And then fatten up again, so they’re fat for the next leg of migration because when they leave here they fly, again, straight to the arctic from here,” Karpanty says.
A handful of young red knots land on the beach nearby. They’re just a bit bigger than a robin, and begin running down to the water to find food.
“Exactly, they are running in and out of right where the water line meets the shore. They are sticking bills down in the sand. And they are probing for little tiny surf clams called coquina clams,” explains Karpanty.
Red knots became federally listed as threatened in 2015. Researchers are still trying to learn why their numbers have been dropping. One of their biggest food sources, horseshoe crab eggs in the Delaware Bay, have been declining, and there are efforts to manage that risk.
University of Virginia researcher Lauren Brideau is helping with today’s count. She’s been analyzing red knot population data over time, and looking for answers about how this species is doing.
“These birds are flying so far and using many different habitats during their life,” Brideau explains. One of their most important habitats are their breeding grounds in the Canadian arctic, where it’s very remote and difficult to study.
“And we do know that their breeding success varies with snow pack, and with the predators up there,” says Karpanty. “And obviously snow pack in particular is changing with climate change. So we know that, but there’s still a lot we don’t know about the arctic.”
Karpanty says the good news is their numbers appear to be holding steady here in Virginia. She’s hopeful that will continue.
“Some of these islands will be able to keep pace with sea level rise, and will be able to move and keep gaining sand and stay above water. But not all the islands will,” Karpanty says.
“And so, I suspect this landscape will look very different in 50 years than it does now. I still think it will be serving as important migratory and nesting bird habitat, but you know our kids will see a very different landscape than we see.”
Many of the barrier islands where red knots go are protected, and may have restrictions to protect nesting and migratory birds. If if you want to see red knots and other migratory birds, Karpanty suggests reaching out to a local eco-tourism group that can bring you.
