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Fulmar (Fulmarus glacialis)
The fulmar belongs to the family known as the Procellariiformes,
or the tubenoses, which also includes petrels, shearwaters
and albatrosses, among others. This is the only member of
the family in the north Atlantic which does not nest in a
burrow, as it is large and strong enough to send any threat
on its way. Fulmars nest on high cliffs above the kittiwakes
and the guillemots, in cracks and crevices in the rock. One
of the adults always remains with the egg, and when an enemy
approaches, the adult can spit oil for a distance of two or
three feet.
This oil smells intensely unpleasant, and is composed of
fats and vitamins A and D. It is a mixture of excretion and
secretion, and is produced in a stomach gland. It is similar
in composition to preening gland oil. The young chick is fed
on this oil, but later on is given more solid food. All of
the procellariiformes vomit when stressed, but it is only
the fulmar that has adapted this trait to a defensive purpose.
The chick instinctively spits at its parents for a few days
after it hatches, until it begins to recognise them.
The fulmar is master of its element, and can fly smoothly
through the fiercest storms of the Atlantic ocean, gliding
over the most troubled waters. You can watch them on Skomer
riding on the wind that comes up from the Wick. They are carried
until they almost hit the rock, and then turn a tight corner
to avoid doing so, hardly moving their wings at all. Every
movement of this bird is smooth and concise, and looks completely
effortless. They seem to enjoy playing on the wind, turning
in large, leisurely circles near their nest sites. All the
birds in this family are excellent divers, though they do
not stay long under the water, nor dive very deep, so they
catch most of their food on or near the surface.
Fulmar populations have increased in the north Atlantic in
the past 200 years. This is almost certainly because of the
waste that was thrown into the sea from the whaling industry
in the nineteenth century, and later on from the fishing industry.
These birds are always seen in large numbers following fishing
trawlers.
Because the fulmar nests on cliffs, instead of in a burrow
like the rest of the family, it has been easier to observe
their behaviour during the mating season. It is probable that
the courtship of the rest of the family takes a similar pattern.
The bird chatters and cackles at its partner, opening its
beak wide and shaking its head up and down and from side to
side, without moving its body. Sometimes, oil is exchanged
between the partners. The male and female show the same behaviour,
and sometimes more than two birds are seen displaying together.
‘Visiting’ by young, unmated birds is a custom that continues
until the egg is laid in May.
The overwhelming majority of fulmars only lay one egg, with
about 1% laying two. Both parents brood the egg, but it seems
that the female does more than the male. They sit on the egg
in shifts of about four days at a time, and there is no evidence
that the returning bird feeds the one that has been on the
egg all that time. The parents incubate the egg for 53 days,
and the chick fledges within another 48.
When first hatched the chick’s body temperature is around
10° lower than that of the adult. The parents must continue
to incubate it until its own temperature control system becomes
effective, around the end of the first week. After that, the
parents will not incubate further, though they may sit on
or near the nest. After the beginning of the homeothermic
stage, the parents leave the chick and go out to sea for longer
periods. After about eight or ten weeks, the chick is fed
less often. It seems the parents leave it alone altogether
towards the end of the season. It stays on the ledge on the
cliff for some time after that, living on stored fat and stretching
its wings, and even flying from one ledge to another before
starting out in earnest for the open sea. Young birds probably
spend two years or more out at sea, before returning to land.
They develop a brooding patch on their bodies and come back
to sit on a shelf, but they cannot lay or fertilize an egg
until around 7, 8 or 9 years of age. After that, the fulmar
returns faithfully every summer as long as it lives, is healthy
and can find a mate.
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