Looney Lift-Off: A Video Study
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Clip: Taking
Off! |
Dr. Walter Piper studies the territorial behavior of loons during their summers in Northern Wisconsin. Dr. Piper's video camera gives you a real treat in this video clip of a loon taking off. The video repeats in slow motion. Dr. Piper also tells what to watch for:
"Loons
always takeoff upwind, just like airplanes try to. This strategy maximizes
lift, which they badly need for takeoff, as you can see. (Loons have
incredibly high mass for their wing area -- which is called wing-loading.)
As the loon tries to take off, it runs along the surface of the water
into the wind, beating its wings hard. Loons weigh about 8 pounds,
but their wings are same size as those of some much lighter ducks.
To take off involves a lot of flapping and a lot of work. Even with
this speed, there is often not enough air pressure beneath the wings
to create 'lift' to get the loon up in the air. If there is a good
head wind, that increases the air pressure under the wings, allowing
the loon to get up in the air, but it doesn't look like there is much
wind here. Notice how the film clip ends with the loon close to the
opposite shore. It will have to swim back and try again. Look carefully
at where its feet are, and how hard it is to lift the body. Notice
how as it tries to take off the bird holds its neck straight out, compared
to the curve of its neck when it was swimming."
Try This! Journaling Question
- When
loons are in danger, they can either take off or sink into the water
and come up somewhere else. After watching this video clip, explain
why being able to dive and swim is very important for loon safety.
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