It has been something of a remarkable autumn, with fantastic numbers of
Short-eared Owls arriving in the county from breeding grounds further north.
Many of these birds are likely to have made a substantial sea crossing; setting
out from Scandinavian breeding grounds their arrival ‘in off the sea’ charted
by birdwatchers all along the Norfolk coast. This autumn, there was a report of
fifty of these stunning birds arriving at Titchwell in a single day, very much
a red-letter occasion for the owl enthusiast.
Short-eared Owls are generally recorded arriving from mid-September
onwards, with numbers peaking during October and a few stragglers arriving into
the beginning of December. Some will remain on the coast, haunting the grazing
marshes, but others move further inland to the fens or the riverside marshes at
places like Halvergate and Chedgrave.
These owls are often portrayed as opportunistic wanderers, nomads that track
the volatile breeding populations of their favoured small mammal prey. In a
good vole season the owls do well and I suspect that this has been one such
season. Come the end of summer, however, the small mammal population may
sometimes crash, prompting the owls to look further afield for a meal. This
combination of a good breeding season followed by a decline in prey abundance
may drive the mass arrivals here but there is still a great deal that we do not
know about these birds and their movements.
With its piercing eyes, tendency to hunt in daylight and buoyant flight,
the Short-eared Owl holds a special place in my affections. Seeing one lifts
the spirits on those flat winter days out on the marsh. Seeing several in the
air together leaves me grinning from ear to ear! The buoyant flight, a
characteristic shared with the Barn Owls that also hunt these wild places,
comes about because of the shape of the wings. The broad wings are
energetically efficient, allowing the owl to slowly quarter the fields and
marshes over which it hunts, while scanning the ground for prey.
Examination of Short-eared Owl pellets – like other owls, Short-eareds
cough up the undigestible parts of their prey – reveals that their winter diet
in Norfolk is dominated by Field Voles, with other small mammals and small
birds making up the balance. These pellets can be collected from the rough
vegetation in which these birds roost. Some of the roosts can hold a dozen or
more owls, the birds returning to the same site over many days. Knowledge of
favoured hunting areas and their accompanying roosts make the Short-eared Owl
one of more reliable winter visitors, providing viewing opportunities for the
birdwatcher. In cold weather they can be surprisingly approachable (with care),
affording stunning views.
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