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3:40-4:40pm, 3/3/2023, Centennial Woods Natural Area, Burlington, VT, cloudy with snow covered ground, ~33 degrees fahrenheit, forested area near stream.

On this trip to Centennial Woods Natural Area in Burlington, VT, I focused on the evolution and ecology of bird species in the winter season. One of the things I looked at was what different bird species do to produce/retain body heat, as these cold Vermont winters can be brutal. It always fascinated me how birds could survive such harsh environmental conditions, so it was super fascinating to see. I noticed that I observed more birds in heavily wooded areas and less near open spaces. I can imagine this is to shield them from the wind and to seek more warmth. I also saw a lot more activity near cavities and snags in logs and dead trees which is where a lot of birds reside for a warmer space.

The birds seemed to be budgeting their time based on energy. Since it is winter, birds seem to be conserving their energy by staying in so I did not see them flying around much—mainly just hearing their calls from tree to tree. However, when they are moving around, they are looking for food. In the winter, it is harder to find food as it is more scarce. However, I noticed that birds look for critters living in trees and also eat seeds from plants that are not covered by snow. The birds primarily look for foods high in energy in the winter which is found in seeds. In contrast, there are much more fruits and bugs available for birds in the summer, so the diet differs tremendously based on the season. It is also currently not breeding season, so energy is not spent by birds there. In the winter, their energy it seems is mainly spent by searching for food and by keeping themselves warm.

In the Centennial Woods Nature Area specifically, I would say various birds are staying overnight in snags and cavities. When on my excursion, I observed hundreds of dead trees with cavities in them where many bird species could survive overnight. I think that this is common in heavily forested areas, as it is a great place for birds to stay warm over cold winter nights and through harsh environmental conditions. Overall this was a very interesting outing, and I found out a lot about the evolution and ecology of birds through my observations today!

4:00-5:00pm, 3/24/2023, Centennial Woods Natural Area, Burlington, VT, sunny with partial snow covered ground, 40 degrees Fahrenheit, forested area.

Birds observed: 16 Black-capped Chickadees, 6 Tufted Titmice, 4 House Finches, 10 White-breasted Nuthatches, 3 American Crows, 1 White-throated Sparrow, 1 Dark-eyed Junco, 1 Northern Cardinal, 5 Ring-billed Gulls, 2 Blue Jays, 1 Hairy Woodpecker

On this trip to the forest within Centennial Woods Natural Area, I specifically watched how birds that I observed interacted with each other. Having it be one of the few sunny days I have seen here this month, I was not surprised to see a ton of birds out and about and interacting amongst each other. I found that there were a lot more birds interacting with each other through calls than I would typically hear. I noticed that a lot of birds of the same species were foraging for food and would stick close to each other. When one would stray from the group, I observed that certain calls or noises were made, for what seemed to be, keeping the location of each other in check. Typically when close together it would sound quieter, short cheeps and chirps but if one would get a little further away, they would get sharper and louder. I observed this in both Black-capped Chickadees and White-breasted Nuthatches that I watched for a while on my trip to the woods.

I also thought a lot about differences between bird species and the evolutionary advantages to each color/pattern that each plumage had. For instance, comparing a Hairy Woodpecker to a White-breasted Nuthatch is interesting. Hairy Woodpeckers spend a lot of time up in the trees, and when you look at them, they almost blend in with the bark due to their dark color and are sometimes difficult to spot in the trees. The White-breasted Nuthatch on the other hand has a gray back that can blend in with bark as well, but also has a white underside and can blend in with snowy areas. It is interesting to see just how different birds fit into their environment so nicely. It is clear that evolution of colors/patterns of the bird affected their plumages which is really cool to see!

Lastly, I also looked into bird behavior in regards to circadian/circannual rhythm. It is clear that a bird’s biological clock has a huge effect on its behaviors and how it allocates its time and resources. It determines when a bird wakes/rests, when they forage for food, when they sing and make the most calls, etc. When I went out to the woods, I began my observations at 4:00pm and the birds were very active with their calls and I noticed many of them foraging for food. Specifically, I heard many White-breasted Nuthatches out and about and foraging for food. They were very vocal at this hour as well. At the end of my trip a little after 5:00pm, the birds seemed to be slightly less active in their calls and foraging, but there was still a great deal of activity. I wonder what I would observe if I made separate trips throughout the day and made comparisons of activity of different species. It is definitely something I plan on doing looking forward!

11:00am-12:00pm, 3/29/2023, Perkins Pier Waterfront, Burlington, VT, sunny and windy, 42 degrees Fahrenheit, lakefront park—mainly open with some wooded areas.

Birds observed: 16 Ring-billed Gulls, 7 Herring Gulls, 4 European Starlings, 5 Common Grackle, 2 Canada Geese

For this bird-watching trip, I decided to go to a new location—the Burlington waterfront! On this trip to the lake, the weather was lovely with it being sunny with few clouds in the sky, although a bit windier the closer that I got to the lake. Today I decided to focus my attention on migration.

Today, I did not observe any birds that do not migrate which I thought was pretty interesting. But when considering other Vermont birds that are here year-round, I think of birds like Blue Jays and Northern Cardinals and their physiological/behavioral adaptations that allow them to survive here year-long. Since they don’t migrate, there has to be some sort of physiological adaptation for each species that allows them to survive the cold, harsh winter weather. These birds find dense foliage to reside in to keep warm, and they also have secure access to food year-round. Additionally, these birds have physiological functions and certain feather types that are well adapted for cold, harsh winters compared to other birds. For these reasons and others, it isn’t necessary for them to migrate like other birds in the winter.

I did, however, observe many Ring-billed and Herring Gulls. These birds migrate out of Vermont in the winter in search for warmer areas with open water so they typically head south. Now that the weather is warming up and the lake is not frozen over, they are heading back into town. I observed many of them today, but I anticipate to see many more in the upcoming weeks due to the warmer temperatures.

After migrating for winter and returning to Burlington in early April, there can be some advantages and disadvantages. Advantages would include better nesting and recovering from any nest loss as well as increased breeding success. However, early April weather in Burlington can be very unpredictable. It could be sunny and warm or it could be freezing temperatures and blizzards. You never know! So in that case, it would be a disadvantage for birds who are not acclimated to that kind of weather where it can be difficult to search for warmth, food, and shelter for survival.