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Razorbill (Alca torda)
The razorbill is in the auk family, along with the guillemot
and the puffin, birds that have evolved to be able to use
their wings under the water to ‘swim’ effectively for fairly
large distances. Indeed, their wings are more effective underwater
than they are in the air, as being so short and narrow. They
cannot swim strongly against the wind, and are easily overtaken
by gulls in flight. Under the water, the wings behave as strong
paddles, and the webbed feet help with the steering.
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The razorbill returns to land a little later than
the guillemot, usually appearing for the first time
in February, but they do not establish themselves on
the rock until April. They also migrate further south
than the guillemots. When they congregate on the water
in early spring, they display in large groups together,
swimming around their partner, opening their mouths
to show the bright yellow interior, and making guttural
noises. Sometimes a third, or even a fourth bird comes
to join in the dance. Sometimes lines of birds form,
with birds facing each other, creating almost formal-looking
patterns. These patterns only last a fraction of a second,
however, before the whole group breaks up or dives below
the surface. The birds all behave very excitedly during
this period.
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Razorbills nest on cliffs, often mixed up with the guillemots,
though they prefer a little more shelter, and tend to occupy
slightly deeper cracks in the rock. Like many seabirds, they
return to the same nesting site year after year, and in this
way, find the same partner year after year. Their life history
is fairly similar to that of the guillemot, the female laying
a single egg which is incubated on the ledge for 35 days.
After hatching the chick is fed on fish and plankton. The
chick grows very quickly, but by two weeks of age the chick
is less than half the weight of an adult, though they have
a full coat of feathers, apart from the flight feathers on
the wings and the tail. The chick begins to exercise its wings
and starts to move around on the shelf, calling discontentedly
for a while, and in the end the young bird jumps off the cliff
at dawn or dusk, and falls to the sea to be led away from
the land by one or both of its parents. If it leaves the cliff
in rough weather, it may have difficulty freeing itself from
the rocks and the waves. Despite this, even if it does hit
the rocks on the way down, it does not usually suffer serious
injury, and continues its descent to the sea. It may be submerged
by the waves, but dives and swims ahead skilfully, calling
nervously every time it breaks the surface. The parents call
encouragingly at the chick throughout. Once they have arrived
at the open ocean, one of the adults (it is not known which
one) stays with the chick to defend and feed it for a period.
All the auks moult their feathers and grow new ones after
leaving the breeding area, and there is a period at the start
of autumn when they can hardly fly at all. The razorbill is
much whiter in its winter plumage.
It is unlikely that the young razorbill will return to its
birthplace in the following year, nor even (perhaps) the one
after that. The auks take three years or more to reach sexual
maturity, but often visit their breeding sites during that
period, in order to locate a nesting position for future use.
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