Great snipe is the fastest migratory bird ever discovered
Great snipe displaying.
Apart from its long, elegant beak, the great snipe looks just like any other wading bird. But researchers have found that this ordinary-looking creature could well be the fastest bird on Earth – over long distances at least.
A lot of birds can fly either very far or very fast, but it's rare to find one that can do both. The peregrine falcon is possibly the fastest bird on the planet: it reaches a startling 200 mph, but only while diving to catch its prey. And the Arctic tern flies further than any other bird during its migration – around 50,000 miles from the Arctic to the Antarctic and back again. Although this is an incredible feat for such a small bird, it doesn't fly at great speed.
"We know of no other animal that travels this rapidly over such a long distance," write the authors in their report, published in the Royal Society journal Biology Letters today.
What's also unusual is that its migration route takes it over land that is perfectly suitable for a stopover.
"We never expected record-breaking flights for this ordinary bird. Along its routes, the snipes have plenty of opportunity to stop over and feed on earthworms, insects and other invertebrates and this is exactly what land birds normally do," says Dr Raymond Klaassen from Lund University in Sweden, lead author of the study.
Migratory birds almost always choose to stop over during their migrations if they can, at a place where they can rest and re-fuel before continuing their epic journeys.
Even though Arctic terns fly over the Atlantic, they still stop to re-fuel on surface fish on the way. On the other hand, the bar-tailed godwit flies from Alaska to New Zealand with no stopover, 'because it has no choice,' says Klaassen.
Flying long distances has its costs. Migratory birds need to have the necessary fuel onboard before they set off. This invariably means they're not agile, because they have to be so fat, which could make them vulnerable to predators. But that doesn't seem to put the great snipe off.
Before this study, scientists had almost no idea where the endangered birds go once they leave Scandinavia.
"We thought they might go to Africa, but we didn't know where. Also, nobody sees the great snipe over the rest of Europe. We put this down to them being so elusive and thought tracking them would reveal the other places they hide," says Klaassen.
The only real way to find out was to fit them with tiny tracking devices, called geolocators.
These devices – developed at the British Antarctic Survey – weigh just 1.1 grams and, including attachments, make up a fraction of a per cent of an adult bird's body weight. They record light intensity; when this data is fed into a computer program, scientists can figure out when and where the birds travelled.
After the breeding season, but before the annual migration, the researchers fitted 10 male great snipes at Jämtland in Sweden with a geolocator each. Exactly a year later, the scientists managed to retrieve three geolocators from three birds when they returned to Sweden after their northward migration.
Klaassen and his colleagues found that one bird flew 4,225 miles from Sweden to central Africa in just 3.5 days. The other two birds flew 3,833 miles in three days, and 2,870 miles in two days.
"We think maybe the feeding conditions are so good in Scandinavia, the birds take advantage of the opportunity to feed up," Klaassen says.
Indeed one report says that come autumn, the birds are so fat, they're barely recognisable from how they looked in May.
The great snipe is an endangered species. "Its numbers have gone down a lot, and it's almost disappeared from mainland Europe. It's now restricted to the mountainous regions of Norway and Sweden," adds Klaassen.
The feeding grounds seem to be more important than researchers realized. "We need to find out exactly where they're feeding and what they're feeding on. It would be good to see them before they migrate, when they're really fat," he says.
Scientists have long known that snipes are incredibly fast birds. The word 'sniper' originated in the 1770s among soldiers in British India: if a hunter was skilled enough to kill an elusive snipe, he was called a sniper.
Great snipes breed in Scandinavia from mid-May to early-July. The birds leave their breeding ground from early-August onwards. The return northward migration happens between March and April.
Other fast creatures
• The Arctic tern tops the list for furthest ever migration, flying 50,000 miles from the Arctic to the Antarctic and back again every year
• Cheetahs are the fastest creature on land (over short distances), reaching speeds of 75 mph within three seconds of a standing start - faster than most sports cars
• Peregrine falcons dive through the air at speeds of around 200 mph to catch their prey
• The sailfish is the fastest fish, reaching speeds in excess of 70 mph
• Dragonflies are the fastest flying insect on Earth, sometimes flying at 40 mph
This story is republished courtesy of Planet Earth online, a free, companion website to the award-winning magazine Planet Earth published and funded by the Natural Environment Research Council (NERC).
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