apbray's Journal

I started my walk on Thursday, April 5th around 11:30 am. It was about 28 degrees Fahrenheit outside, but the sun was still shining. I walked in a mix of mature tree stands, young tree stands, and open fields. The first species I saw was a Downy Woodpecker that was foraging on the edge of the trail near some houses. As I continued down the path I saw a murder of American Crows that were calling to each other. As I got closer to the more mature tree stands, I stood on the edge of the walking path and saw two Pileated Woodpeckers fly into the woods. Before I could take a picture of them, I saw two birds fighting above me and one of them was a Yellow-bellied Sapsucker, which I wasn't able to identify until I got home. I went further into the woods and photographed one of the Pileated Woodpeckers for a while, and noticed to my right there was a Hairy Woodpecker that was also foraging. I continued walking and came to a younger part of the forest where I saw some Passerines, such as the Northern Cardinal, American Robin and White-breasted Nuthatch. The Northern Cardinal was calling to some other individuals in the area.

One species I observed that foregoes migration is the Northern Cardinal. The Northern Cardinal is a generalist species, and eats many kinds of fruits, insects and nuts. Birds that don't migrate have better chances of maintaining their territories year-round, and don't have to face the hazards of migration. Northern Cardinals have some behavioral adaptations to survive winter's cold; Northern Cardinals fluff up their feathers and tuck their heads and feet in to maintain body heat. Birds can also put on fat in the winter, so most species that stay in Vermont in the winter forage during the day for fatty foods, hence why bird feeders become so popular in the winter. Some birds also undergo facultative hypothermia at night to lower energy consumption.

One species I observed that is a migratory species was the Yellow-bellied Sapsucker. This species was coming from Mexico and Central America, and migrate to upper North America. This species probably started migrating north because there were more resources available up here that weren't being used up by another species. There are multiple factors that could've caused them to come back, including a change in climate (such as a change in wind patterns), timing and location changes in predation, and different food types and their supply in the environment. An advantage of this individual returning to Vermont early is that, if their food is available, they can replenish their energy stores more fully than individuals that arrive later in the season, and thus will be more fit for breeding. They can also claim territories before other individuals arrive. However, an obvious disadvantage to coming back this early in April could be that their food is not available yet; in the case of the Yellow-bellied Sapsucker, because the temperatures are still below freezing, it may not be able to access sap as well as it would if it arrived later in the spring.

I began my bird walk around 1:15 pm on Thursday, April 19th. Although it was around 43 degrees Fahrenheit, snow began to fall at the end of my walk. I started my walk by walking towards a large puddle where I heard frogs peeping, and noticed a lot of birds hanging around the puddle, searching for insects. This was a younger part of the forest, with a lot of large snags. I saw a Northern Cardinal on a log above the puddle, trying to catch insects. I watched for a while, then continued on. Across the walking path I heard birds calling to each other, and recognized them to be Ovenbirds, a species new to me. I wasn't ever able to see them because they were too high in the trees, so I walked on. I walked all along edge habitat, but the woods were made up of mostly mature tree stands with a lot of large snags. I saw a lot of Hairy Woodpeckers that were foraging on trees, fairly close to me. I also saw a lot of Black-capped Chickadees who were very close to me, and didn't seem bothered by me approaching them at all. I was next to some cliffs, and noticed a very small, round bird foraging with the Black-capped Chickadees on a northern white-cedar tree, and got home to identify it as a Ruby-crowned Kinglet. There was definitely a lot of activity, even at this time of the day, and I'm sure as more birds migrate back to Red Rocks, it'll be one of the best birding spots around Burlington.

On Wednesday, April 25th I walked through the Intervale in Burlington, Vermont, from 11:20am to 12:30pm. The weather today was rainy, but around 55 degrees Fahrenheit. The habitat here varied quite a bit; it starts off in a secondary growth forests with big cottonwood trees and sandy soils. The trail followed the Winooski River, and across the river was marsh habitat. Towards the end of the trails are large, open fields that provide great habitat for edge species.

I saw a great range of species today. Although, I felt that I didn't see a lot of the birds I was hearing, which may be due to the fact that across the river, trees were being cut down and might've scared them off. However the species I did see were exhibiting a lot of different behaviors. First of all, I saw three Hairy Woodpeckers fighting over territory; I saw a male chase off two other Hairy Woodpecker's, making loud calls as he did so. They were definitely fighting over prime territory, because they were right next to the river, and there were a lot of small snags in the area which other bigger woodpecker species, such as the Pileated, probably wouldn't use. The male I saw fighting off the others was probably of the highest fitness, because he could spend that energy fighting rather than foraging, and will probably get more females than the individuals he chased away (assuming they were also males). But what is prime territory for these Woodpeckers might not be prime territory for everyone; a Mallard might think prime territory is the marsh across the river, and prime territory for a Common Grackle could range from a forest edge to a city park.

I also saw an American Robin gathering materials to build a nest. In it's beak it was carrying straw or dead grass, which it probably got from the farmed fields a couple meters away. Robins use straw and twigs to build their nests, and I saw a completed nest at eye level in a tree on my walk as well. The American Robin could get materials for its nest anywhere in the woods or the field that had twigs or straw, which were not limiting resources. However not every species builds a nest in the open such as the American Robin; a lot of other birds such as the Black-capped Chickadee, Tufted Titmouse, Hairy and Downy Woodpeckers, and sometimes Winter Wrens will use cavities in trees or other natural cavities for nesting. I also saw a pair of Brown-headed Cowbirds, which don't have to build nests; they're brood parasites, and will lay eggs in other birds nests for them to raise. I could tell the pair of Cowbirds I saw today was a breeding pair because the male was following the female from branch to branch and singing to her and puffing up as he did it.

My mini activity was pretty successful this week. Because the trail I was walking was fairly open, it was easy to follow where sounds were coming from. For example, when I was walking I heard the Northern Flicker from all the way across the river to my right, but could detect that an Eastern Phoebe was right above me.