The other morning I was treated to an enthralling display by a small
flock of Snow Buntings. The birds, flashing a blizzard of white wing and tail
markings, rolled as one as they twisted and turned above one of the lagoons at the
RSPB’s Titchwell reserve. At first I was not sure what they were up to, the
flock sweeping low to the water almost as if the buntings wanted to land. These
are small birds (only slightly bigger than a House Sparrow) and, with no wading
birds close by with which to judge the depth of water, I could not imagine that
this is what they were attempting to do. Perhaps the buntings themselves were
unsure, this would explain the hesitant passes low to the water, but then,
suddenly, three birds broke from the flock and landed, the others sweeping back
around to join them. The buntings had revealed the water to be far shallower
than it appeared from my position on the bank and I had to smile at the way in
which these delightful birds had broken that particular optical illusion.
These Snow Buntings were not the first of the winter and I had
encountered other groups over previous days, notably at Cley and on Blakeney
Point. Here the birds were in more characteristic habitat (for the winter),
foraging on the ground amongst the sparse vegetation of the sea wall. This
winter preference for our coastal fringes contrasts with the high montane
breeding grounds, located high in the Scottish Highlands or further afield in
Iceland and Greenland. The Scottish breeding population is small, but thought
to be self-sustaining, and is thinly scattered over a wide area. Here the birds
nest among boulders, located close to long-lasting summer snow fields.
Snow Buntings are to some extent nomadic and the numbers wintering
around the Norfolk coast can vary substantially from one year to the next.
Ringing studies have revealed an exchange of birds with the Low Countries and
there is even a record of one reaching northern Italy.
One of the most engaging things about a feeding flock is the way that
they maintain a steady, almost conversational, trill as they feed. They are
also fairly tolerant of a human observer. When viewed as a single entity, the
flock seems to roll across the ground, as individuals dash to the front to
search new ground for seed. Another feature of these flocks is the way they
just disappear into the background, their patterned plumage providing effective
camouflage on the shingle. You can watch a flock fly in, dropping down onto the
shingle not 30 feet from you, and then you struggle to pick them out. Once you
have found them, however, they are magical.
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