Field Journal 3 - Ecological Physiology

March 6, 2021
Temp: 18 degrees F
Wind: 10 mph
Start Time: 9:25 am
End Time: 10:30 am

Birds who over winter here in Vermont and in colder climates need to adapt to the cold in order to survive. One example of this are crows. In the colder months they are seen roosting in large groups. These groups are used for sharing information on where good food sources are, and even for huddling together for warmth. Other bird species are also seen in groups, and these groups can be mixed species flocks. One mixed species flock that was seen today was a flock with Black-capped Chickadees, White-breasted Nuthatches, Red-breasted Nuthatches, and Brown Creepers. These mixed species flocks are also used in the same way the crow roosts are used for - sharing food source information. Since there are no insects out and about to eat over winter, birds have to work with what is available. In the winter that means conifer seeds, fruits from ash trees and apple trees. Some species also cache food from seasons with more food variety in cavities for wintertime. Nuthatches and Brown Creepers can pick up the bark from trees and eat the dormant insects underneath the bark. Those like the Downy Woodpecker, and other Woodpecker species, can create holes in snag to find dormant insect in the trees. For warmth during the night birds can stay in groups like crow roosts or in cavities in trees or coniferous forests. Those things will help with insulation and warmth.

These cavities in snags are used for a variety of things and they are a shared resource. As mentioned, before they are created by woodpeckers looking for insects. Depending on the size of the cavity a variety of different birds can use them for nesting, and to sleep in for warmth and a wind guard. They can also be used for a place to cache food. Owls, Nuthatches, Black-capped Chickadees, Tufted Titmice and Woodpeckers often use these cavities.

Julkaistu maaliskuu 7, 2021 10:03 IP. käyttäjältä esmith7