Diario de sdurant

On April 2nd, I went on a walk down by the waterfront of Lake Champlain. I went on the walk after my Ornithology class at around 11 am. It was between 45 and 50 degrees and the sun was shining. I heard a lot of different birds like Black-capped Chickadee's, Northern Cardinals, Blue Jays, Tufted Titmice, Woodpeckers, and Nuthatches. I also heard some birds that I couldn't figure out what they were. These birds were in a thicket of trees and were hidden. I only got a picture of one bird but I couldn't really tell what it was. The recording titled Northern Cardinal is from that thicket and you can hear multiple different bird calls and songs during the recording.

All the birds I heard on my walk are year-round residents. Birds like Blue Jays, Black-capped Chickadees, Ravens, Tufted Titmice and many more decide to stay rather than migrate. They might forego migration due to the fact that it is so energetically expensive. They have a better chance of survival and use less energy staying where they are. Since we live in an area that gets pretty cold, they have to be able to survive in the sub-zero weather. These birds have a high reproductive rate but they also have a high mortality rate. To keep warm they will shiver, huddle, fluff out their feathers, go into torpor, etc. Black-capped Chickadees specifically go into facultative hypothermia which helps to conserve heat. They also have ways to cool off during the high temperatures during the summer.

The facultative migrants are coming from the south and stopping by on their way north. Facultative migrants typically move short distances and are flexible with the timing of migration. Since these birds are flexible, they notice when it starts to get warmer/colder and the skies start to clear and they migrate then. We have had a few warmer weeks in March before the snow storms and that might have given these facultative migrants a false sense of the weather. This caused them to move back up north before actual springtime. Obligate migrants are hardwired to migrate at the same time every single year, regardless of warmer or colder weather. Advantages are that they are coming at the beginning of spring and are expecting warm weather with easy access to food. An advantage is that they are most likely coming after the facultative species meaning that they have less competition for food. A disadvantage is in cases like this week, when it snows in April and once again food becomes scarce. The snow along with the cold weather makes it harder to find food and survive for these species that are not used to it.

Mini Activity: Every bird that I saw and heard was a bird that is a year-round resident. Thus they do not migrate and stay in the area.

I went for a walk by Lake Champlain again on April 18th. I went for the walk around 11 am and it was about 40 degrees out. I saw the American Robin on the dirt next to a sidewalk. The Song Sparrows I saw and heard when I passed by a thicket of trees. That is also where I spotted the nest. The tree holding the nest was close to the outskirts of the thicket. I also heard Black-capped Chickadees and Crows in that area as well.

I visited the Intervale walking trails in Burlington Vermont on April 25th. I went for the walk around 11 am and stayed there until 12:30. It was around 50 degrees but it was drizzling for most of the trip. I heard more birds than I saw. I heard a Northern Flicker across the body of water and saw a Mallard fly over the same body of water. I saw Brown-headed Cowbirds, Downy Woodpeckers, Red-winged Blackbird and Northern Cardinals on the edges of the forest. The Mourning Doves, American Robins, Song Sparrows, Pileated Woodpeckers, Crows, and Hairy Woodpeckers were deeper in the forest.

The Brown-headed Cowbirds I believe were showing mating behaviors. There were two of them sitting on the same branch and It sounded like the male was singing to the female. Every now and then the male would move slightly closer to the female. I didn't really see any other mating behaviors. I did see quite a few nests but there weren't any birds in the ones I saw. I found the most nests kind of up high and deeper into the forest. There were probably some that were near the edge too but I didn't see those ones. The deeper into the forest the nests are and the more hidden they are in the trees help to protect them from predators. The nests were probably also placed int he optimal places to get food. Birds that eat seeds would probably be near the plants and trees they get those seeds from. Birds that eat bugs would probably be the ones deeper in the forest and closer to the bottom of the tree.

The Downy Woodpeckers were fighting over territory. I heard intense singing and screeching. Then one Woodpecker started chasing two others away from the area. I would say it was protecting a prime territory. It seemed that there were a lot of Woodpeckers in that area and there were quite a few dead trees, which means this is an area with an abundance of food. I would say that the bird that drove all the others away is probably the strongest fit and the "alpha" since it seemed that once he started freaking out all the other birds left. The American Robin would probably build its nest out of mud, twigs, leaves, and other materials found on he forest floor like pine needles. I don't think they would have to go far since most of those materials can be found on the forest ground and right below the tree where their nest is.