Fresh chapter for whimbrels

“One sunny, but very chilly day, a baby whimbrel (that’s a bird) hatched out of an egg. His dad was right there beside him.”

So begins Winston’s Journey, the tale of a fledgling whimbrel. The character is based on the annual life cycle of hundreds of real birds, their story discovered by a sophisticated scientific study by Natural England and volunteers at the Lower Derwent National Nature Reserve.

The whimbrel is a smaller cousin of the curlew, but much rarer. Back in the 1970s, one or two appeared in Yorkshire each spring, en route from their wintering quarters in West Africa to nesting grounds in Iceland and Northern Scandinavia.

In 1987, a small evening roost of the birds was discovered at Wheldrake Ings, on the River Derwent. Since then, the numbers have grown steadily and the nature reserve’s senior manager, Craig Ralston, now puts the numbers arriving each spring at approximately 150, making it one of the biggest migration roost sites in the UK. No-one knew why.

Iceland’s east coast or around the Swedish-Finnish border is where many European whimbrels go to breed. In late summer, they set off on the 5,000-mile journey to West Africa to spend the winter and then, each April, they migrate north to their nesting grounds.

During the past 10 years, the Whimbrel Study Group has found that many of the birds have an uncanny way of turning up here on the same date each year.

“For the last seven years now, the first three whimbrels have arrived on April 16,” Craig says. “I think it’s pretty amazing.”

When the roost was first discovered, nothing was known about what happened to the birds between the time they flew away from the reserve at daybreak to their return at dusk.

Craig and the volunteers, experimenting with the use of radio tags, found that the birds were feeding on the other side of the River Derwent.

Closer study of their feeding habits revealed they were confining themselves to fields with a certain soil type and ones that had been maintained in a traditional way with grazing by cattle. They were eating mostly earthworms and the ground had to be moist enough for the birds to probe with their long, curved bills.

The importance of the fields was further underlined when it was found that the birds were arriving in Yorkshire weighing 300-350 grams, but before setting off for Iceland, their body weight had almost doubled. The Derwent fields, therefore, supplied the fuel for that final leg of the journey.

This land was outside the Lower Derwent Valley National Nature Reserve, and no special conservation measures were in place. The fields could be ploughed up or drained, destroying the whimbrels’ migration food.

Says Craig: “Imagine a plane setting off for Australia from England and having to make a refuelling stop at Bangkok, but then finding that the airport’s closed. What happens? You’re stuck. Well, it would be the same for the whimbrel.”

The answer was to safeguard the fields used by whimbrels, bringing them into agri-environment schemes and paying the farmers to manage the fields specifically for the feeding whimbrels.

This has meant that farmers have not installed under-draining, not used them for hay-making, and have kept them for cattle grazing rather than horse paddocks.

Some birds were fitted with satellite tracking devices, and these filled in the story of what happened to the birds when they left Yorkshire.

They flew directly to Iceland on a journey that took them 24 hours, and, after breeding on the east coast, they switched to Iceland’s west coast.

Craig believes this was to feed up on bilberry for the non-stop 5,000-mile flight to Africa in late summer.

The importance of the work at Lower Derwent is shown by the fate of two other members of the whimbrel/curlew family.

Both the slender-billed curlew and the Eskimo curlew have become extinct because of loss of feeding habitat on their respective migration routes in Asia and the US.

The book, Winston’s Journey, says Craig, is a way of explaining to a new generation how important it is to continue protecting the whimbrels’ vital refuelling place in Yorkshire.

* Winston’s Journey by Jayne Murphy, with illustrations by Lorraine Berkshire-Roe, is available to children along the Lower Derwent Valley. For details email [email protected]

* Further information at www.whimbrel.info

LONG-DISTANCE TRAVELLERS

Once the whimbrel chicks are able to fly, they spend several weeks feeding to build up their reserves of energy. Then, in late summer, they set off on the 5,000-mile journey to Africa, especially to the Republic of Guinea and Guinea-Bissau. They spend the winter feeding in mangrove swamps, usually catching small fiddler crabs. And then, in April, they migrate north to their nesting grounds. There’s historical evidence suggesting that their arrival in Yorkshire each spring goes back at least until the 19th century. Their local name of “May Bird” suggests they are traditionally seen in May.