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The
Gannet
Is a fast and powerful flyer but
its short legs and large webbed feet make it awkward at landings and
take-offs
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Can see forward with both
eyes—which is unusual in birds
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May glide for hours just above the
wave tips, seldom moving its wings
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Occupies the same nest year after
year, until
it becomes a substantial heap of feathers, fish skeletons, and
droppings
Adult gannets have dazzling white
plumage except for narrow grey spectacles and jet black, tapering wingtips.
During the breeding season, the head and neck assume a delicate saffron yellow
tinge. The eyes are an icy blue, and the bill is blue to
grey-blue.
Young gannets in autumn
plumage are brown, with many white flecks. With the passing of each season, they
become progressively whiter, reaching the complete adult plumage in their fourth
or fifth year.
The Northern
Gannet is well equipped by nature for its spectacular plunges for fish from
great heights.
Unlike most
birds, it has binocular vision—that is,
its eyes are positioned such that it can
see forward with both.
This presumably gives it the
ability to estimate how far the fish are from the surface of the water. Its
strong, streamlined bill is 100 mm long. It has no nostril holes, and its upper
and lower bills fit tightly together so that little if any water is forced into
the mouth on impact with the surface.
Its streamlined body has a system of air
cells between the skin of its neck and shoulders and the muscle beneath. As the
gannet prepares to dive, its air cells are inflated to cushion its body when it
strikes the water.
A Northern Gannet in flight is supremely
graceful.
The wings of an adult bird may span almost 2 m
and are narrow, tapered
toward the ends, and
swept back slightly, like those of a gull. Its long strong bill extends forward
in flight,
tapering smoothly into the small head, which
merges with a thick neck
that in turn joins the body in a clean, smooth contour.
The legs are tucked well up under the
smoothly tapering tail. The gannet’s shape appears to offer minimum resistance
to air flow.
Few seabirds are more spectacular in
their fishing methods than this one. The gannet may fly alone
or as part of a
group, usually cruising 18 to 30 m above the sea.
When a gannet sees a fish in the water
below, it dives more or less vertically, with partially folded wings and great
speed. Its impact with the water may send spray as high as 3 m, and the
momentum
of its dive is thought to carry the bird below its prey.
Swimming strongly with the aid of its
large webbed feet, and possibly at times with its wings, the
gannet captures its
prey. On reaching the surface,
or even before, it swallows the fish and takes
off to resume the hunt or to return to the gannetry to feed its nestling.
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