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Razorbills belong to the auk family, along with
guillemots and puffins.
They look rather similar to guillemots but their dark
feathers are black
rather than chocolate brown, they are plumper and have
thicker, heavier-looking bills. On the water, a
razorbill floats higher than a
guillemot and its longer tail tilts upwards.
The razorbill is
well-named because
the edges of its hooked upper beak
are very sharp indeed,
enabling it to grasp fish well and to defend itself against predators.
Razorbills eat
mainly fish such as sand eels but they also eat molluscs (snail-like creatures),
crustaceans (crabs etc.) and planktonic worms. Fish are carried crosswise in the
bill, in the
same way as the puffin does.
Up to eight fish
can be carried at once. Razorbills, guillemots and puffins
do not compete directly for food because guillemots catch large fish, which they
carry singly; puffins catch small fish and razorbills catch medium-sized fish.
Razorbills spend
much of the year well out to sea.
As with other auks, they are expert underwater
swimmers, using their wings. A razorbill
takes off from the water rather clumsily, feet pattering along
the surface, but then it flies strongly with rapid wing-beats. During the late
summer, the birds moult all their flight feathers at the same time, making them
unable to fly for a while.
Razorbills nest
in colonies in remote, sheltered
holes and crevices in cliffs, among boulders on
rocky foreshores; sometimes they choose a puffin hole but only very rarely
use exposed
ledges chosen by guillemots. The birds arrive
at their colonies from the end of January onwards, but breeding begins in
earnest in April. No real nest is made, except sometimes
a
few plants or stones are used.
A single egg is
laid from early May onwards and
both parents incubate it for 33 - 36 days, and
then share the feeding duties. At about 18 days old, the still down-covered
chick launches itself from the cliff, fluttering down on tiny wings, usually at
night to avoid predatory gulls.
They often fall
onto rocks or into
heavy surf but
they are well protected by fat and feathers and can swim
strongly. Their parents continue to
feed them out at sea until they can fly and fend for themselves.
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