Gulls must be the most neighborly of creatures at Halibut
Point. They don't mind your civilized presence, at a certain remove. They never
take their eyes off you, but they rarely scold either. They never try to hide. If
you get too close they lift off into the air.
Gulls come to Halibut Point for some of the same reasons I
do, stepping away from crowds and cares to straighten out their feathers. They
animate the quarry where the stillness might otherwise seem ghostly. They have
an aboriginal presence when I walk unannounced into their busyness.
At the quarry they gather amicably for a fresh-water bath
without squabbling over scraps. Generally they stick to the center to minimize intrusion.
The confabs of Herring gulls and Great black-backed gulls
sometimes include Ring-billed gulls.
Sooner or later they get on to preening and drying chores on
a nearby ledge, or circle up and out to prospects
at sea.
The masters of flight decelerate with tail and body arched,
wings articulated for split-second adjustments, primary feathers opened on the
up-stroke to lessen drag and maintain lift. They maneuver as smoothly as we
reach for a doorknob.
They pull themselves through the air by reaching forward
with their wings, not by pushing them to the rear. Wingtips bend and rotate to
the task of propulsion. The wings scull in figure-eights to contribute forward
momentum. Counter-intuitively, to our logic, the power stroke ends with the
wing swept far forward.*
Rising off the water is hard work for heavy duck-like birds
that taxi on their feet and flap vigorously. Birds favored to soar, like gulls, achieve
lift by simply extending their cambered wings in a light wind. Air flowing
faster over the upper surface than below it pulls the bird upward passively. Similar
pressure differentials make a spinning baseball curve and are mimicked in
aircraft design.
Adaptations in the gull's honeycombed skeleton, its feathers and its
diet give it advantages for inhabiting all the continents and oceans of the
earth. Modern anatomical research illuminates these facts without reducing the
wonder of their coordination into a particular life. That wonder can be
freshened with every ramble at Halibut Point.
* See "Flight" in Chris Leahy's The Birdwatcher's Companion.
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