Delta Park & Ethan Allen Homestead; March 3/4

I visited Delta Park, Ethan Allen Homestead, the Colchester Causeway, and the Burlington waterfront all in one weekend in search of the mystical snowy owl and to take some pictures of more common birds. It was a relatively chilly day, somewhere between 30 and 40 degrees, with overcast skies. I was told Ethan Allen Homestead would be a good spot to go, but I did not expect to find so many birds in one small patch of forest (while the rest of the park was mostly empty). Delta Park contained the same common species, white-breasted nuthatch and black-capped chickadees, but it is always a nice place to visit.

One of the most common body heat conservation behavior I saw was the repeated fluffing of feathers and preening. I saw this behavior in the black-capped chickadee, tufted titmouse, herring gull, and dark-eyed junco. They would shake their whole body to fluff up their feathers in order to utilize their down feathers better. I also saw a good amount of preening of the contour feathers which I would assume is to increase their insulation ability.

All of the forest foraging birds I saw were foraging for the entirety of the time (except for a few individuals who were preening). They were mostly in mixed species flocks of 3-8 gathering seeds and small fruits from tree limbs and twigs anywhere from a few feet off the ground to the lower canopy. I noticed they would forage a singular spot and then fly and come back. I suppose this could be them caching their seed for later consumption, ensuring they have a food storage through the winter. In more productive seasons, like the summer, I would expect these small foraging species to consume more insects for their higher nutritional value. They are just not present in the winter. I did not see any breeding behavior or any individuals sleeping.

In the Ethan Allen Homestead I noticed that almost all the birds were all centrally located in one small patch of forest near the Winooski River. None were to be found in the agricultural fields or even a forest patch within the bordering the fields and river. The patch where they were located seemed to have a higher diversity of trees and understory vegetation, possibly providing more food resources.

It was not surprising to find that most of the tree cavities in snags were located where I found the highest abundance of birds. There were close to a dozen snags that I saw within the patch and all of them had at least two cavities in them. It seemed from quick observation that the larger trees tended to have larger excavations, but it also seemed to depend on what species created the cavity. I noticed the larger rectangular cavity of a pileated woodpecker and the smaller limb cavities of the downy woodpecker. Tapping on the snags did not bring out any curious avian creatures. These cavities are crucial to the survival of our winter residence for the shelter/warmth it provides in the harsh winters. I believe most of the smaller forest foraging birds utilize these cavities, sometimes in larger groups occupying an individual cavity. Without them these smaller birds would most likely not be able to survive.

Posted on March 20, 2018 03:15 PM by srotella