FLYING AROUND THE FARLEIGHS
THE FARLEIGHS' FALCON'S FIREWORKS?
Sorry for the laboured alliteration, I can hear the groans even as I’m writing it. But the fireworks reference is timely, and my attention was recently alerted to the awesome hunting skills of a sparrowhawk in my garden. This led me to think it would be great if, once the ooh-ing and aah-ing at the fireworks is over, we might like to consider the awe of another spectacular night-time display that has just been revealed by science.
I’m referring to Peregrine Falcons, now surprisingly common in Kent, including birds that regularly patrol the Medway Valley and surrounding Farleighs farmland, using the pylons to spy out their prey – usually pigeon-sized as it’s not worth their while expending precious energy on taking anything smaller. A garden songbird, for example, would be to them as a few peanuts with a G&T are to us.
At this time of year millions of birds are on the move, migrating south from their breeding areas in northern Europe to warmer climes further south for the winter, and local keen birders listen out for their calls as they pass over in the night. Ornithologists have theorised that many birds migrate at night to avoid airborne predators like falcons – although the light spilling from urban areas now means that peregrines, at least, can and do hunt successfully at night. They also believe that species that migrate by day fly at an even greater height to avoid those same predators but have not been able to prove- or disprove -it. Until now.
Earlier this year scientists in the Netherlands fitted sophisticated satellite tags to Grey Plovers (close relatives of our commoner Lapwings) trapped on their northward migration to the arctic to breed. Amongst other things these tags measure the height the bird flies at, as well as time, speed and distance.
On 25th May, at 25 minutes after sunset, travelling at a height of 3,000 metres over Sweden (nearly two miles high!) one of the tags showed the bird had not only stopped flying, but had suddenly descended extremely quickly – much faster than it would if it has just died. The most likely explanation was that the bird had been hit by something travelling fast enough to take it straight downwards towards the ground, indicating that it had probably been killed by a hunting peregrine. Peregrines hunt by stooping at up to 200 mph from above their prey and have been recorded flying at 5,600 metres (three miles above sea level) on their own migratory flights.
Unusually, evidence to prove this theory came to light when birdwatchers chance upon the remains of the grey plover with its satellite tracker intact – close to a peregrine’s nest in Sweden.
So enjoy the Farleigh Firework display, but let your imagination soar beyond – miles beyond - the bursting rockets to wonder at the natural wildlife spectacular taking place out of sight above us.