22 de febrero de 2021

Field Journal 2

Date - 2/21/2020
Start time - 4:00 p.m.
End time - 5:30 p.m.
Location - Burlington Bay, Burlington, VT
Weather - 25 degrees Fahrenheit, sunny, low wind
Habitats - freshwater lake, city

I got to observe a probable ring-necked duck's flight for around thirty seconds. It took a bit to get off of the water, and it stayed within a few feet of the surface for its entire flight. Its wingbeats were fast and mechanical. The duck's wings were medium-length but very narrow and pointed.
I didn't get any pictures of the gull I observed, so it's not in my observations. Compared to the duck's flight, the gull's was more acrobatic, with slower wingbeats and a higher elevation. Its wings were also narrow, but considerably longer than the duck's.
We discussed the effects of wing-loading and aspect ratio on flying ability in class; the gull and duck provide good examples of how different species optimize their wing shape and size for their lifestyle. Ducks usually fly for short distances and spend most of their time in the water, so they can afford higher wing-loading, and while their high aspect ratio means they need more lift to get off the ground, they can still easily take off from the surface of the water. Gulls have lower wing-loading because they spend more of their time foraging, which means they need to be able to fly without expending much energy. They have longer wings to allow for dynamic soaring, but they still have a higher aspect ratio than, for example, a red-tailed hawk.
The fast, mechanical flapping of a duck's short wings are very characteristic of ducks, so even though I wasn't able to make out the markings on my "ring-necked duck", I could tell it wasn't a gull or a cormorant. The gull was even further away, but their wide wingspan, maneuverability, and combination of soaring and fast wingbeats are pretty distinctive.

Anotado en febrero 22, lunes 21:59 por hilarygood hilarygood | 4 observaciones | 0 comentarios | Deja un comentario

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