Late March
3/28/23
9:00-10:00 am
Behind the Shaws in Winooski
Sunny, 35°F, Little-No wind
Parking lot bordering forested cliffs
On today’s bird watch I observed several species that I have encountered throughout the past few months, including Black-capped Chickadees, European Starlings, American Crows, and American Robins. These species possess adaptations that allow them to withstand the frigid temperatures of Northern Vermont winters. One example of a cold adaptation can be found in the Black-capped Chickadee. These birds enter a nightly hypothermia, in which they decrease their body temperature by 12-15°F below their daytime body temperature. This physiological adaptation allows them to reduce their metabolic expenditures and conserve energy, greatly increasing their chances of survival through cold nights. Other year-round residents employ behavioral adaptations to withstand chilly temperatures. The American Robin fluffs its feathers to create a warmer coat. This behavior increases feather depth by three times which increases insulation by up to 50%.
While in my location, I heard the trilly call of the Red-winged Blackbird. The greater Burlington area lies at the southern end of the bird's breeding range. There is a good chance that the birds I heard singing have completed or were nearing the completion of their journey north. Red-winged Blackbirds spend the winter foraging on grains and seeds in Southern US states and Mexico preparing for their migration. They migrate in pursuit of greater food availability. Because of this annual movement, they are not especially well adapted to withstanding cold temperatures. As Spring begins, the Vermont landscape provides a wide array of new food opportunities. These blackbirds eat fruits, insects, and spiders, all of which are emerging this time of year. I saw several Canada Geese flying north from my location. These birds will reach some of the most northern parts of Canada during their breeding season. Canada Geese migrate to avoid competition, find suitable nesting habitats, and pursue both abundant food and more daylight. In total, the migratory birds (Canada Goose, Common Grackle, and Red-winged Blackbird) that I observed in an hour have a maximum combined migration distance of 5,470 miles.
Species List:
A group of about 20 Cedar Waxwings
3 Red-winged Blackbirds
10 Ring-billed gulls
2 Canada Geese
2 European Starlings
1 Common Grackle
3 Black-capped Chickadees
5 American Crows
5 American Robins
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