Field Journal 3: Ecological Physiology
Date: 3/7/2021
Start time: 1:00
End time: 2:35
Location: Oakledge Park
Weather: sunny, clear sky, 24 degrees F, some small gusts of winds
Habitats: open field and forest with white pines, eastern white cedars, red oaks, and rock polypody ferns
The first species I saw was the Black-capped Chickadee and there were 14 individuals or so that were flying from tree to tree at high heights in the white pines. This activity can keep them warm by constantly moving and using the insulation of their feathers. They are also likely searching for food which can give them energy for thermoregulation. Another species I was able to observe directly for a longer period of time was the White-breasted Nuthatch. There were two individuals also flying from tree to tree and excavating the red oaks and white pines from top to about midway. They would stop to take a break only for a moment, shiver a little, and then get back to searching for possible insects or seeds. They seem to be using similar mechanisms to stay warm, they are almost constantly moving around with short breaks where they would shiver to warm from the muscle contractions and are also on the search for food in order to gain energy to maintain body heat.
While looking at the snags, I noticed that the larger the snag, the larger the cavities are as well as a larger number of cavities. On one eight-foot snag from an old white pine, there were varying sizes of cavities, some were about half the size of a human head and some were half the size of a human hand or smaller. There were also two living white pines attached to the snag which may be why this snag had so many cavities. The majority of bird observations in this trip were around the area of the snags. The Chickadees, White-breasted Nuthatches, and the Tufted Titmouse were all seen or heard in the area where I found snags.
I tried tapping on some snags with a large branch but no birds popped out. The reason for this is due to the time of the day since the birds are likely searching for food during the day, when it is warmer, and hiding away in these cavities during the night in order to keep warm and sheltered. Snags are important for winter nesting or cavity nesters like Nuthatches, Titmice, and Woodpeckers who can use these cavities for protection from the weather and predators. They are also important for the summer when the heat of the day is too hot and they use them for shade.