Red Knot’s epic spring migration includes North Carolina

Red Knots are visible during the spring migration on Ocracoke Island. Photo: Peter Vankevitch

Reprinted from Ocracoke Observer

The red knot is an amazing bird.

Only about the size of an American robin and usually weighing less than 5 ounces, it performs a marathon migratory flight.

Most of these nodes, the rufa subspecies, overwinter in Tierra del Fuego, the southernmost tip of South America.

From there, their over 9,000 mile route to their nesting grounds in the mid and high arctic regions of northern Canada is one of the longest migration routes for a bird. Although some red knots overwinter in the United States – with most years in Ocracoke – Florida has the highest number.

These incredible migrants are also at risk of extinction, and information about their migration through North Carolina can aid population recovery efforts.

These shorebirds made the news this spring when the annual Red Knot survey in the Delaware Bay area noted a dramatic decrease in numbers.

This bay is an important staging area as Red Knots feed primarily on normally abundant horseshoe crab eggs before resuming their migration to the Arctic.

A red bow on Ocracoke.  Photo: Peter Vankevitch
A red bow on Ocracoke. Photo: Peter Vankevitch

The dismal numbers – around 7,000 reported in the Delaware Bay area – signaled a significant drop in their numbers, which is about a third of those counted last year in 2020 and the lowest since the early 1980s , when the population was around 90,000.

Much of the blame has been attributed to the overexploitation of horseshoe crabs for baits and biomedicals.

Other reasons for the precipitous fall include climate change and sea level rise, coastal development, reduced food availability in coastal stopover areas, and human disturbance from vehicles, domestic animals. , low-flying airplanes and motor boats.

In 2020, horseshoe crabs did not arrive in Delaware Bay when Red Knots passed due to unusually cold ocean waters.

Horseshoe crabs are present in and around Ocracoke, but not in numbers in the Delaware Bay area.  Photo: Peter Vankevitch
Horseshoe crabs are present in and around Ocracoke, but not in numbers in the Delaware Bay area. Photo: Peter Vankevitch

Without this important food source, it is feared that many nodes did not survive their long journey to the Arctic last spring, which would explain the extremely low number this year.

Some theories for low numbers suggest that when they can’t find enough food sources a year, they can avoid those areas and find others.

Ocracoke Island and other areas of the Outer Banks have seen a good number of whales pass during the spring migration over the past two years.

According to information provided by the National Park Service, a May 12 survey produced a maximum number of 1,100 red knot, surpassing the highest number of 750 in a single day in 2020.

The Core Sound area of ​​the Cape Lookout National Seashore was home to 1,838 individuals on May 16, which Meaghan Johnson, head of resource management and science for the eastern North Carolina national parks, said was the highest number of peaks in this region since 2016.

Significantly, observers noted frantic feeding behavior as the nodes strengthened for their long remaining flight to the Arctic.

With the reduced number of sandpipers recorded in Delaware Bay, the number of red knots passing through North Carolina is becoming more important, said Jon Altman, supervisor of resource management at Cape Lookout National Seashore.

This view was shared by Larry Niles, an independent wildlife biologist who once led the New Jersey Endangered Species Program. He has been monitoring bird migration on the New Jersey side of Delaware Bay for 25 years. He said the species’ best hope for survival lies in a total ban on harvesting female horseshoe crabs until the crab population recovers.

“We need to know more about the Red Knot’s migration through North Carolina,” he said.

It is not known if these Tarheel nodes stop in the Delaware Bay area after their refueling stop in the Outer Banks. It’s worth considering attaching radio geolocation beacons to some to track their movements to help identify important stopovers and length of stays during their epic migration.

To learn more about the Red Knot, visit Birds of Ocracoke: The Red Knot.

Red Knot in basic plumage wintering on Ocracoke Island. Note the red and white stripe on the right front individual. Photo: Peter Vankevitch

This story is courtesy of the Ocracoke Observer, a newspaper covering Ocracoke Island. Coastal Review is partnering with the Ocracoke Observer to provide readers with more interesting stories about the environment and way of life along our coast.


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