Researchers look at Dominion offshore wind farm and whimbrel migration pattern

Each summer, a group of brownish, long-billed shorebirds called curlews feed on crabs on the east coast of Virginia before heading south to Brazil.

Experts know where this journey begins and where the birds end. Less is known about their exact flight path over the Atlantic Ocean. And in a few years, there could be an obstruction there.

Dominion Energy plans to build a wind farm 27 miles off Virginia Beach. It would consist of 176 wind turbines each measuring more than 800 feet – taller than the Washington Monument. The location was previously chosen to be away from most bird migrations, but some species could still be affected, the company and researchers said.

A local team is now studying whimbrels in particular, trying to determine if they are flying where the turbines would be – and if so, if they are flying high enough to pass through them.

“The potential conflict with the turbine field is cause for concern,” said Bryan Watts, director of the Center for Conservation Biology at William & Mary. “It’s an open question…. There may be a conflict, but there may be no conflict at all.

Watts’ team hopes to answer that question, in partnership with the nonprofit Nature Conservancy. Dominion provided approximately $300,000 for the two-year study.

Birds rest on a mudflat off Willis Wharf on the east coast. It is in this area that the researchers recently captured whimbrels for their study.

On a recent morning, the waters were calm and the sun was warm as Watts disembarked from a boat from Willis Wharf on the east coast. He was joined by Alex Wilke, a coastal scientist from the reserve’s Volgenau Virginia Coast Reserve, which runs the migratory bird program.

They took out binoculars at low tide to search for whimbrels in the surrounding mudflats.

It was probably last week that the species could be spotted on the shore; their numbers tend to peak in late July before they begin to fly south.

While here the birds feast on fiddler crabs, with some increasing their body weight by around 50% to make it to South America, Watts said.

The research team spent several weeks in August trapping and tagging whimbrels to track their flight path in the Atlantic. They finally sent 15 birds with tags.

To trap the birds, Wilke said they use mats called slipknot mats. When the bird steps on the trap, it wraps around its leg to prevent it from flying away. Crew members constantly monitor the area, so the birds are not trapped for long. Then the bird is measured, weighed, fitted with a transmitter and released.

Once a day, the transmitter tries to send data through the nearest cell tower, Watts said. If it can’t – like when birds fly far out in the ocean – it stores the data until it can transmit. Researchers can then track the birds via an online dashboard.

This isn’t the first time they’ve tried to hunt down Whimbrels.

About a decade ago, researchers at Eastern Shore attached transmitters to birds, hoping to figure out why their numbers had been declining by about 4% per year since the 1990s. learned more about the whimbrel’s annual cycle, which includes returning to Virginia on their way back from South America and ultimately to the Arctic to breed.

“Projects like this, where we’re sort of working locally but thinking hemispherically, that’s the only way we’re going to learn these important lessons and really be able to effectively protect these species in the future.” , said Wilke.

This time, they are particularly interested in the altitude at which the whimbrels fly. This is data that previous technology did not capture and will help determine if the turbines are a problem.

The Virginia Beach farm will be among the first offshore wind projects in the United States, but there are many elsewhere in the world.

Watts said he tried to assess what others had learned about birds and the offshore wind.

It’s a mixed bag. Some species run into turbines, as has been a problem on land. Others are “evaders,” Watts said, and fly around equipment.

“Birds react in different ways,” he said. “Not all birds are the same in terms of potential benefits and impacts.”

Problems on land often stem from the fact that wind farms are placed in wildlife corridors, he added.

The advantage of a project so far offshore is that it is beyond many migration routes – except for a few, such as the whimbrel.

“That’s what this project is about.”

Researchers recently captured whimbrels for the tagging study in a marsh off Willis Wharf on the east coast.
Researchers recently captured whimbrels for a tagging study in a marsh off Willis Wharf on the east coast.

Two pilot turbines were installed in the Dominion Federal Concession Area in the Atlantic Ocean in the fall of 2020.

Since then, the company has been conducting its own wildlife research — in addition to funding others, largely within regulatory requirements, said Scott Lawton, environmental technical adviser for Dominion.

They learned a lot, he said.

Some things were more expected – like a phenomenon where concrete structures attracted sea life in search of habitat. But the cameras also captured bats and species Dominion didn’t expect so far from land: butterflies, dragonflies and other insects.

The study of corlieu curlews is an extension of the research.

Matt Overton, biological consultant for Dominion’s corporate biology department, said he came from a bird focus group regarding the offshore wind project that included various environmental organizations.

“One of the biggest questions that no one really knows is how high and how high do these birds migrate?” he said. “We don’t want to be in a situation where we have high bird mortality.”

So if there is a problem with the turbines, what happens next?

It depends, but Overton said he doesn’t think the issue will move or stop the project. Instead, officials might need to look to seasonal operational conditions when the birds pass.

While offshore wind farms are expected to become more common along the East Coast in the coming decades, the company and researchers understand that the knowledge gained from the project will be valuable beyond Virginia. But Watts said the east coast is a special place for whimbrels. It is the only significant place where they stop on their way both north and south.

“It appears that, at least for populations that use the West Atlantic flyway, these birds have built their annual cycle around the east coast. So this place is really very important.

Read the original story on the WHRO website.

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