26 de março de 2020

Journal Entry 3

With everything that has been going on over the past few weeks, this assignment really slipped through to the last second. Since I had been feeling a bit sick (not bad, but a cough so better not to risk it) and since I tend to see a lot of birds outside my window, I decided to go sit on my roof for the hour and a half. I was there from 5:00 to 6:30 today, March 25. The weather was overcast and in the low 40s. The habitat around the area tends to consist of largely of urban buildings, with large deciduous trees and smaller conifers.

Keeping an eye out for bird interactions was very interesting, and my vantage point allowed me to really get a good view of how groups of birds moved and interacted. One interesting species I paid attention to were the crows. First I noticed a lone crow in a low branch, making for of a cackling call for over 5 minutes, which stretch me as interesting given their tendency to flock over the past 4 months. I also noticed another group of 13 perched together in a couple of trees, and was able to notice how some pairs of birds interacted much more closely than others, and even noticed a few perch evictions by what I would assume were higher ranked birds. There was also an interesting large group of gulls that seemed to be feeding on something just out of view. The perches on the closest rooftops seemed to be a hot commodity, and there was definitely some competition between the gulls. I also noticed some take big circles away from the food, perhaps perch somewhere else for a minute, and then return. I wonder if this behavior has something to do with feeding in the ocean? The last group that I thought was interesting was a group of European starlings that were scared off by a cardinal, but returned to their previous spot a minute or so later.- The movement of the starlings was very interesting, they seemed to sometimes all move together and other times move one by one. The groups also seemed like they were constantly shifting and changing, despite it seeming like none of the birds were going very far.

Many of the behaviors I saw made me thing about territories, despite not being sure that territorial behavior explained anything that I was seeing. Without an ability to keep track of individual birds, it was a tough task to tell if repeated flying routes were the same bird or different birds. However, it did seem that smaller birds traversed a smaller area than larger birds. The starlings seemed like they stayed within the place of 3 or 4 houses, while the gulls flew over more than a few blocks every time they left the feeding spot. The blue jay was a nice intermediate that I was curious about, bit I didn't see it too many times and it was difficult to tell how large of an area it was keeping to. However, just due to its speed, I could tell that it was flying further than the starlings, and the small flights between perches could indicate a smaller area than the gulls. Since it was nearing the end of the day, this might make sense, as foraging is likely finishing up for the day.

I didn't really spend too much time looking at plumages this time around, but the bright colors of the blue jay and the cardinal stood out to me, and I wondered what life history traits would make it so these birds can afford to stand out so much in a dangerous world.

Since I was sitting on a roof, I didn't want to act like even more of a crazy person pishing for birds. I have done it many times in the past, however, and sometimes it indeed has the power to draw in small birds. After thinking about it for a while, I don't have a good guess on why the birds are interested, but I figure it probably sounds like swishing leaves, which may be a cue for something?

Publicado em 26 de março de 2020, 02:36 AM por lucasferrier lucasferrier | 6 observações | 0 comentários | Deixar um comentário

07 de março de 2020

Journal Entry 2

Date: Tuesday 3/3/2020, 3:45-5:30p
Location: Winooski Gorge Park (44°29'19.7"N 73°09'45.6"W)
Weather: very overcast, with a high chance of rain. Mid 40s, a warm day compared to the past few weeks/months.
Habitat: Largely coniferous forest at the top of a gorge. Small patch of forest, close enough to a main road to hear fairly heavy traffic. Still a large enough patch to house deer, ran into many tracks and droppings.

This walk was full of bird calls but very scarce on bird sightings. The walk started in a very clear conifer stand, and continued through other stands of varying density. There were also a few overlooks over a gorge with a view of the water, but the lack of a shore and the fact that the water was frozen seemed to discourage waterfowl. This may have been different during the summer; the trees and tops of the gorge likely could have created good perches for ospreys or other fish-eating birds. From these outlooks, I could see hordes of crows flying overhead, which we learned is a very common winter behavior for corvids. They tend to form murders in winter to maximize survival chances, but these groups cause food to deplete quickly, causing the birds to move often.

In the forested area, it seemed that bird activity was pretty low. I heard a lot of various sparrow, finch, and warbler calls, but had difficulty identifying most of them. These birds, however, stayed very hidden throughout my walk. I found a couple of black-capped chickadees because of their curiosity, but nothing else. There were many chickadee alarm calls, so maybe the other birds were being cautious, avoiding the big scary bipedal mammal. Alternatively, maybe minimizing foraging time during the winter could help birds keep their energy demands low, so perhaps some of the birds had already finished their foraging and returned to their roosts. Especially for birds that cache food, it may not take long to forage if they are able to remember where they left their stores. When observing the chickadees, I noticed that they tended to stay in coniferous trees that were well foliated, avoiding bare trees. This could be a common strategy for birds in winter, as it helps them remain hidden from predators when the deciduous trees drop their leaves.

For the snag watch I noted 5 different trees of various sizes. I was unsure about the definitions of snags and cavities. I just noted obviously dead or fallen trees as snags, and counted any hole that seemed large enough for a bird as a cavity. The list of snags and characteristics is as such:
1. medium sized conifer snag, about 65 inches in diameter at breast height. Not decomposed enough to lose much structural stability. Contained a variety of medium sized cavities, likely from a pileated woodpecker.
2. small conifer snag, about 10 inches in diameter ABH. Lacked any major signs of decomposing. Small cavity present near the base, but not signs of any inhabitants.
3. large conifer snag, about 85 inches in diameter ABH. showed some signs of decomposing, had lost all but a few major branches. Contained a variety of medium and large sized cavities, likely from a pileated woodpecker.
4. large conifer snag, about 80 inches in diameter ABH. This one was fallen, but didn’t contain any significant cavities that I could find. I wonder if woodpeckers dislike fallen trees.
5. large snag, pretty much just a tall stump at this point. Likely was a conifer, likely about 50 inches in diameter ABH. This one contained many large cavities, but again no signs of inhabitants.

Snags likely provide a nesting place for many small bird species in these type of woods, based on the snags that I was on my walk. These places of refuge are probably even more beneficial in the winter, when cover from harsh conditions may be more hard to find.

Publicado em 07 de março de 2020, 01:35 AM por lucasferrier lucasferrier | 4 observações | 0 comentários | Deixar um comentário

18 de fevereiro de 2020

Field Journal 1

For our birdwatching trip today, I went out with Gretchen to the intervals on cross country skis. We spent our hour and a half finding various places along the trail to look for birds. The habitat was nice and diverse, with the Winooski river providing terrain for water birds, plenty of trees for various songbirds and woodpeckers, and open fields that let us peruse large swaths of sky for larger birds. As noted in our observations, we saw plenty of interesting species, despite being loud on skis. I was especially excited to see the goldeneyes, which I barely spotted on the other side of the river. Even through binoculars, we could barely see them enough to get an ID, so I'm excited to try for find more up close.

For the assignment for today, we spend some time watching the white breasted nuthatch and a black capped chickadee. These birds are fairly similar in morphology, especially when it comes to wing structure. Both have mostly elliptical wings, and like to flit between branches in small bursts. One difference I noticed was that the nuthatch seemed like it spent more time in the same perch, exploring my traversing the tree on foot, while the chickadee spent more time flying between branches that were very close together. My guess for this difference in behavior is their difference in food sources and territory. Since nuthatches cache food and do not flock like chickadees do, they may be more inclined to stick to a specific area for foraging and food storage, while chickadees may be more likely to spend a small amount of time foraging at many different sites.

For my drawing today, I didn't have a lot of time to sit and sketch the birds that we saw. There was no feeder or anything to keep the birds in the area, and they were far away to be able to see the markings in detail. Instead, I drew one from a photo, just to get better acquainted with the markings of the bird. I couldn't figure out how to upload the drawing.

Publicado em 18 de fevereiro de 2020, 11:54 PM por lucasferrier lucasferrier | 6 observações | 0 comentários | Deixar um comentário

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