14Ingham’s W RLD
WHEN humans fly long haul our jets reach for heights that dwarf Mount Everest.And so, it turns out, do many migrating birds. Great snipe, cousins of our own snipe which are longbilled waders, reach as high as 28,000ft on their way from northern Europe to tropical Africa.
These remarkable birds really do go long haul, flying 3,700 miles in one wing-sapping journey in as little as 60 hours. They clock up speeds of up to 60mph on this marathon, which must require a bit of support from the wind. They also fly much higher during the day, dropping down to about 6,500ft when flying at night, Sweden’s Lund University tells Current Biology.
Snipe are not alone in this. Europe’s great reed warblers drop from a daytime migration height of 20,000ft to 6,500ft at night.
The Lund team don’t know why snipe fly in more rarefied air in daytime but it may help them dodge predators or avoid extreme heat over the Sahara. Higher daytime altitudes may also make navigation easier. The snipe just won’t say.Their long bills are sealed.
They may, of course, be trying to ride strong winds going in the right direction. Perhaps when the sun disappears, the winds change.
But their high-flying antics are far from unique.
The RSPB says the highest altitude British birds are whooper swans from Iceland. A pilot spotted some flying over the Hebrides at a chilly 27,000ft.
Bar-headed geese can top that, having been seen flying over the Himalayas at 29,500ft – just clearing Everest.
In 1973 a Rüppell’s vulture was caught at an altitude where we would have needed oxygen tanks and thermal clothing. It collided with an aircraft at 37,000ft and suffered the ghastly fate of being sucked into the engines.
You’ve got to feel for it. There it was, wheeling up in the ether, as free as a bird, with only the gods as company. What were the odds of it getting swallowed by a plane?
It’s the bird world equivalent of over-confident Icarus who flew too close to the sun and plunged to his death when the wax holding his feathers together melted.
But the vulture hadn’t been cocky. It was just in the wrong place at the wrong time.