Field Journal 5
Date - 04/05/21
Start time - 3:09 pm
End time - 4:49 pm
Location - Red Rocks Park, South Burlington, Vermont
Weather (temperature, wind speed/direction, precipitation) - 54 degrees, 15mph wind NNW, sunny
Habitat(s) - white pine, beech, and white birch forest with swampy spots and plenty of underbrush; rocky lakeshore; grassy forest edges along walking trails
My phone died shortly into my birding session, so I saw many more birds than I got to document. I'll list them here before responding to the journal prompt.
Northern Cardinal - 2 individuals, male and female
Turkey Vulture - 1 individual
American Robin - 1 individual
Tufted Titmouse - 2 individuals
White-breasted Nuthatch - 1 individual
American Crow - 1 individual
Gulls? - 2 individuals (couldn't see leg color or beak marking to ID as Herring or Ring-Billed)
Cooper's Hawk? - 1 individual (I think Cooper's and not Sharp-shinned because of its size)
Common Merganser? - 2 individuals (based on white wing patches, rapid wingbeats, and head shape)
Winter Wren? - 1 individual (based on upright tail, all-over brown with slightly lighter underside, faint white eyestripe) also may have been a Hermit Thrush
Migration is physically and energetically taxing, so birds that can survive without migration will stay in the same place over the winter. Migrating or not is determined more by food availability than by temperature; if a bird has enough food, it can keep itself warm. Some American Crows migrate, while others stay all winter. Over winter, crows form large flocks that allow many crows to benefit from one crow's discovery of food. They scavenge and will eat almost anything, so they're able to find enough calories to stay warm.
Downy and Hairy Woodpeckers spend the winter in Vermont. They're able to find insect larvae in trees all winter, and they can hollow out shelters in trees to keep warm at night.
Black-capped Chickadees flock together to help each other find food and keep warm. Birds also grow more insulating down in the winter, and puff up their feathers to keep warm by trapping. Some birds can decrease their body temperature significantly over the winter, entering torpor to conserve energy. Others can keep their featherless feet much colder than their bodies to avoid losing heat.
Common Mergansers are migrants, and they usually make their way north early in spring. Vermont has mergansers year-round, but according to All About Birds, all mergansers migrate. The ones arriving for the spring might be coming from southern Vermont or Massachusetts. Decreasing ice cover on the lake makes it possible for mergansers to find food.
I don't think I found any obligate migrants.
Mini Activity: Most of my birds were year-round residents, but the very rough total mileage of the migrants was 1680 miles!
