samharesteig's Journal

Sunday February 21
9:09am to 11am
5-10mph Winds
Blue Sky, 100% Sun
UVM Campus

Today my Mom came and did some birding with the class! She had never gone birding before and really enjoyed it.

I watched several American Crows for a while today. It looked like they had wing types similar to the High-Aspect ratio shape. It seems that the wing shape may give the Crow more lift and a greater ability to glide. The wing shape of the Crow was similar to that of the Herring Gull. Both had more secondary feathers than primary feathers. The Herring Gull that I observed also seemed to be gliding and not flapping its wings very much. It seemed to not be in a hurry to get anywhere and thus using less energy.

I know that crows are generalists: they are able to live in most habitats, whether that be a densely forested area or a more urban area. I wonder if wings that enable them to glide more, allow them to conserve energy and live in a variety of habitats. If they are able to conserve energy then they could live in a habitat that is not ideally suited for their needs. Another potential reason why gliding could be helpful is if the bird is travelling long distances. Maybe the Herring Gull has a large habitat or migrates far away and thus needs to conserve its energy on long flights.

Another species I observed was a Raven. This bird seemed to have a wedge shaped tail. This is distinct compared to the American Crow which has a fan shaped tail. The Raven also looked like it has longer wings, with especially longer primary feathers. This wing shape reminds me of a hawk, which makes me think that Raven wings are closer to the High Speed wing-shape. This might help it with hunting. I also noticed the Raven moving much quicker through the air than the Crow. Possibly the wedge shaped tail of the Raven enables it to break easier after going at high speeds for quick changes of direction. The American Crow may not hunt as much and its fan shaped tail might help it with loft and the conservation of energy.