STREAMING across the south Pennines, from their wintering grounds in Norfolk, Cambridgeshire, and Lincolnshire, Pink-footed Geese head north and west, and back, ultimately to their Arctic breeding areas.
Star deputy editor Paul License spotted about 350 high over Rother Valley last Sunday. In recent decades, the numbers of birds have increased so that the late afternoon sky in winter, in say Wells or Hunstanton in north Norfolk, can be filled with these spectacular birds.
When the sky is full of them, moving from inland fields where they have fed, to the coastal mudflats for the night, it is an impressive sight.
Geese are noisy too, and the sounds and shapes of the birds are distinctive to species even at a considerable distance.
Pink-feet are relatively small with short dark necks and an ‘unk-unk wink-wink’ call. Increased numbers in East Anglia means more birds passing through our area on their double journey; north-west to south-east in the autumn, and the return trip right now.
What we experience in South Yorkshire is a phenomenon called ‘visible migration’, which is what it says on the tin.
Remarkably, as a significant behaviour, this is only regularly experienced in a limited number of areas, and we are fortunate to be in one of them.
A large flock of birds such as geese flying on long-distance migration. will cover maybe hundreds of miles.
They know the lie of the land, which is passed down through the generations, and they use the star-lit sky (if they can see it) and the Earth’s magnetic field as a sort of built-in Sat-Nav.
The chosen height for migration will be several hundred feet, or maybe a thousand or more.
As they head off across the Cambridgeshire and Lincolnshire fenlands, they pass over a few ridges of high ground like the escarpment on which sits the magnificent medieval cathedral at Lincoln, but apart from this, the land is flat and low. Indeed, the first real high ground they come to is the massif of the Peak District and the southern Pennines.
Therefore, if our birds set off flying at about 1,000 feet, when they meet Sheffield and Barnsley at about 500 feet, they are not too far off ground level.
For the human observer at ground level, our great flock of geese is now truly ‘visible migration’ and audible too.
On a clear day, the flocks might pass over the suburbs at well over a thousand feet, but in bad weather and poor visibility, they drop.
Last weekend that is exactly what happened as around 1,000 to 1,500 geese passed over my house in Norton, Sheffield.
You could hear the birds arriving minutes before you saw them; great ragged skeins of birds etched black against the pale sky.
The first flock numbered over a thousand, then a smaller group a few minutes later, and finally a few small groups of birds trying not to be left behind.
The sky was full and a it was a spectacle that you really do not expect in urban Sheffield.
I was discussing the distinctive calls of the Pink-footed Geese with my friend Paul Ardron, and he suggested that they were ‘musical’ and this helps separate them from the noisy but unmusical calls of Canada Geese and others.
I think that fits perfectly, so look and listen.