UVM Field Ornithology Field Journal 3: Winter Adaptations

Date - 3/6/21
Start time - 9 am
End time - 10:30 am
Location - UVM Campus and Centennial Forest
Weather (temperature, wind speed/direction, precipitation) - 16 degrees Fahrenheit, 10 mph wind, ~80% cloud cover, no precipitation.
Habitat(s) - Residential area with occasional pine and crabapple trees; Mixed deciduous and evergreen natural area with a brook running through.

We walked from Aiken down into Centennial Woods. Birds were only present sparsely in open habitats on campus, and were most usually seen foraging in denser vegetation, which could potentially be a behavioral strategy by which they can be sheltered from the cold by vegetation and retain body heat. Birds seen outside of the woods were most often seen foraging on fruits from ornamental crabapples or seeds from pinecones; for birds wintering in the northern woods, insects are absent and fruits and seeds must be the primary food source. The barred owl and juncos in particular seemed to associate with dense evergreen areas. Many of our sightings were part of a single mixed-species flock, including two species of nuthatch, brown creepers, and chickadees. Mixed-species flocks are likely a behavioral adaptation to winter conditions, allowing birds to forage efficiently and pool knowledge of food resources, avoiding energy waste associated with searching alone. Some signs of spring could be seen: Black-capped Chickadees have begun singing, and crows when seen were foraging singly rather than as parts of large groups.

I observed a number of snags, usually in areas where birds were also abundant; for example on the periphery between a residential area with crabapple trees and Centennial Woods. One cavity hole had droppings in the opening, indicating that it was in use by birds. Nothing appeared when the snag was rapped on. Snags shelter birds from the cold and are primarily used overnight by small northern wintering species, including Black-capped Chickadees and woodpeckers. Many of the holes in the snags had limited space inside for a bird to roost; deeper cavities were more rare.

Julkaistu maaliskuu 7, 2021 10:11 IP. käyttäjältä lenarose16