Field Journal 1

Field Journal 1
Gretchen Saveson
02/19/20

1:10pm
3 degrees F
NE 6 knot wind
02/14/2020
UVM campus and North Prospect Street

From the steps of the AIken building, I observed two Rock Pigeons on the roof of the Davis Center. They took flight and flew as a pair along a curvy flight path. No birds were visible on the main part of campus, though I spotted a Ring-billed Gull flying overhead toward Lake Champlain. Its wing flapping was minimal as it glided by. This flight pattern is made possible by the high aspect ratio of gull wings. High aspect ratio wings have a high wing length to wing width ratio that are most efficient for long and fast flight but not well designed for maneuverability and short bursts of speed.This is because each wing stroke in a high aspect ratio wing will propel a bird a greater distance (less profile drag), but at the cost of quick flaps. This wing shape makes sense for the Ring-billed Gull’s niche, as many Gulls often fly long distances over large water bodies. Indeed, the Ring-billed Gull flew in a fast, direct path with few wing flaps.

There were two hotspots of bird activity along South Prospect Street between Main Street and Redstone Campus. In a yard at the intersection of Robinson Parkway, many birds were seen in bushes and small trees in two yards with bird feeders. The combination of bird feeders and shrubs clearly created a refuge for urban birds in the winter. Black-capped Chickadees, House Sparrows, Blue Jays, and American Goldfinches were vocalizing and moving about. Goldfinches flew in an undulating pattern, characterized by a few rapid wing beats of lift followed by a brief period during which wings were tucked and the bird dropped. Calls of “potato chip” were heard as the finch flew- a very distinctive ID characteristic. This flight pattern differed from that of the House Sparrow, which flew in a direct path with even wingbeats. Theory suggests that undulating flight is most economical for slow flight (Rayner 1985). Also at this stop were two White-breasted Nuthatches, crawling along the trunk of a large maple tree. After observing White-breasted Nuthatches, a few identification traits stood out to me; they like to crawl along trees face-down, and they have black tops to their head that stand in sharp contrast to their white face and breast (see drawing). They are larger than chickadees and do not have a black stripe across their eye as chickadees do. A Tufted-titmouse and a Northern Cardinal were also in the snow beneath a rose bush.

The next hotspot was a fruit-bearing tree near the Redstone campus. Over twenty robins were foraging in the branches and nearby area. A few European starlings were also in the tree and nearby bushes. A few Robins were on the roof of a nearby building, drinking from the edge of a melting snow patch on the roof. The final stop was in the redstone pines, where I heard two woodpeckers drumming but was not able to see them.

Publicado el febrero 18, 2020 03:24 MAÑANA por gmsaveson