maggiegrady's Journal

Start time: 16:38
End Time: 17:52
Date: 4/29/2024
Location: Centennial Woods
Weather: 52 F, 6 mph south wind, partly cloudy
Habitat: Mixed hardwood forest with some mature Eastern White Pine stands

Start time: 14:46
End time: 15:46
Date: 4/19/2024
Location: Redstone pines, pond and woods behind Redstone
Weather: 57 F, 16 mph north wind, cloudy, occasional light drizzle
Habitat: Mature Eastern White Pine copse bordered by mature deciduous trees and understory, 2 small ponds surrounded by tall grassy vegetation, small copse of young- to mid-aged deciduous trees

On this walk, I saw a variety of behaviors related to mate and territory selection. Most obvious were the many male birds singing to attract a female. Often, I would see multiple males of the same species singing in the same area, but becoming territorial if the other male got only slightly too close. I found it interesting that so many of these birds flock together (perhaps for safety), yet simultaneously compete for space. For example, I often see American Robins foraging in large groups, but recently I have begun to see them chase each other viciously until one of them moves only a few feet away. European Starlings have behaved in similar ways. To me, this behavior seems like a waste of energy, so I wonder if it truly makes a significant impact on mate selection from females.

I also saw about five Red-winged Blackbirds engaging in intraspecific competition by singing in different locations around two small adjacent ponds. Out of all of the species I've seen on my walks, the Red-winged Blackbirds are the only ones that are consistently around the ponds, showing that their habitat and nesting needs are unique among other common species on campus. According to All About Birds, female Red-winged Blackbirds build their nests "near the ground (or water surface in a marsh), in dense, grass-like vegetation such as cattails, bulrushes, sedges, and Phragmites in wetlands." Using this description, I compared the location qualities of the singing males to determine their fitness. Two males were singing relatively far from the ponds in a tree and on a streetlight, respectively. These positions seemed to be suboptimal because of their distance from the wetland ground, so I can assume that these two birds were less fit. Conversely, I saw three birds occupying either the mats of wetland vegetation atop the pond or the reeds beside the pond, which seemed to be much more preferable locations for attracting a mate.

Compared to these Red-winged Blackbirds, the Common Raven pair seem to be far ahead in the breeding timeline. I saw them collecting sticks and other nest-building materials together on my March 3rd walk, so they likely have been paired up for at least seven weeks. Ravens use large branches to build nests, then line them with softer materials such as pine needles, animal fur, mosses, and soft bark. Many of these materials are found in the Redstone Pines, where I frequently see one or both ravens. On today's walk, I saw one bird sitting on top of the Redstone water tower and cawing. Later, I saw a raven (potentially the same one) flying through the deciduous copse next to the Redstone Pines to forage for food. I suspect that if their nest was successful, it is on the water tower (or somewhere close by) and the eggs have probably hatched by now.

Start time: 14:21
End time: 15:22
Date: 4/11/2024
Location: Woods behind Redstone Campus, athletic fields outside Gutterson Field House, Redstone Pines
Weather: Overcast, damp, intermittent drizzle, 54 F, 10 mph northwest wind
Habitat: Small copse of young- to mid-aged deciduous trees, maintained grassy fields with fencing, mature Eastern White Pine copse bordered by mature deciduous trees and understory

Date: 3/24/2024
Start time: 12:12
End time: 13:21
Locations: Redstone campus, Redstone Pines/Interfaith Center
Weather: 30 F, sunny, 7 mph south-facing wind
Habitats:

1. Lawn with some deciduous trees and evergreen shrubs
2. Mature Eastern white pines with little understory, magnolia shrub, some mature-to-intermediate deciduous trees nearby with more understory

Of the ten avian species I observed, six were resident species in Vermont. These included House Sparrows, Black-capped Chickadees, Tufted Titmice, Red-breasted Nuthatches, Common Ravens, and European Starlings. These are all birds that I have previously observed in winter, although House Sparrows and Common Ravens seem to have become more prevalent now that their breeding season has begun. Resident species typically forego migration because enough of their populations can find food and shelter to survive overwintering, so migrating is not worth the risks and energy input. To survive the winter, resident birds instead employ adaptations such as entering a hypothermic state at night to conserve energy and flocking to share body heat.
The four other species that I observed on this walk were facultative migrants: Song Sparrow, Cedar Waxwing, American Robin, and Ring-billed Gull. I have previously observed these species, but never on a dedicated bird walk and only in the past two weeks. They are all short- to medium- distance migrants and likely came from the southeast or mid-Atlantic U.S. The weather conditions this weekend have been quite cold (about 15-35 F) and very snowy, so less than ideal for migratory birds. Therefore, I assume these birds migrated north a couple weeks ago when it was much warmer, or else were so far away that they relied on timing rather than weather to begin their migration. There has been a massive influx of American Robins (I probably saw at least 50 on my walk today) which are overcoming the snowy conditions by foraging in trees and a grass patch on the Redstone green that presumably straddles a heating pipe which melted the snow.

Date: 3/3/2024
Start time: 17:13
End time: 18:15
Locations: Redstone campus, Redstone Pines
Weather: 44 F, clear, 5 mph south-facing wind
Habitats:

1. Lawn with some deciduous trees and evergreen shrubs
2. Mature Eastern white pines with little understory, magnolia shrub, some mature-to-intermediate deciduous trees nearby with more understory

This week I wanted to experiment with timing, so I took my walk in the evening to see if I would encounter different bird species or behaviors. If I could have done it over, I likely would have gone about a half hour earlier, as noticeable bird activity almost completely stopped around 17:45 when the sun set. This is likely because the diurnal birds' circadian rhythms are set to sleep around sunset.

Despite this, I did encounter some interesting birds, particularly two Common Ravens and a Cooper's Hawk. According to All About Birds, Common Ravens typically pair up between the ages of 2 and 4-- before that time, young ravens often group up and jockey for territory. I found this interesting because I distinctly remember seeing a large group of ravens around campus last year, so I wonder if the ravens I just saw were members of that group and thus recently entered the breeding stage.

The raven pair was perfect to examine for modes of communication, as they are a very intelligent species. Initially, I saw only one raven sitting atop a water tower and making a strange, repetitive noise, then occasionally cawing. Soon afterwards, the raven flew into the pines, and I noticed the second one nearby. Therefore, I theorized that the odd sound was the first raven calling to its mate. This video I found sounds almost the same, which provides evidence to support my hypothesis: https://www.youtube.com/watch?v=EOEZq3aRL_8
Additionally, I observed one raven gathering pieces of twigs and gesturing with them at the other raven, which I perceived to be an attempt to catch the others attention and perhaps a question—such as whether the sticks were of good enough quality for the nest.

The Cooper’s Hawk I encountered appeared to be under a year old, as it still had the signature light breast and brown streaking of immature plumage. Cooper’s Hawks are a forest-dwelling species and active hunters which mainly prey on small to medium birds, so their plumage must provide adequate camouflage before they strike. Thus, they are mottled brown and white in immaturity and become blue-gray and reddish when they mature. Conversely, Common Ravens are mostly opportunistic feeders, eating everything from carrion to eggs to unattended human food. They do not rely on camouflage to survive, so their plumage is very dark, likely because the melanin provides strength to their feathers.

I did not witness the Cooper's Hawk catch anything, but it did appear to be attentively looking for prey in the vicinity as it perched on a high branch. As I did not encounter any flocks of small birds, I attempted to spish the hawk-- it was not particularly amused or disturbed. Eventually, the bird glided away further into the trees, likely to investigate for prey or head towards a roosting place, as it was beginning to get dark.

Date: 2/19/2024
Start time: 14:00
End time: 15:16
Locations: Redstone campus and Centennial Woods
Weather: 23 F, Sunny, 9 mph Southeast wind
Habitats: Open lawn with ornamental trees such as Highbush Cranberry and Eastern Red Cedar; Northern hardwood forest dominated by mature Eastern White Pines and deciduous understory

The weather for this week's bird walk was sunny but cold, so birds were actively feeding to gain energy and conserve heat. On campus, I saw several Black-capped Chickadees feeding on the seeds and berries of what appeared to be a Highbush Cranberry tree. Additionally, I saw a variety of birds foraging around the higher branches of Eastern White Pines in Centennial Woods. Black-capped Chickadees, Red-breasted and White-breasted Nuthatches, and a Brown Creeper were likely feeding on pine seeds, while Hairy Woodpeckers drilled holes in branches and bark in search of insects.

Overwintering birds such as these often form heterospecific flocks which are thought to increase foraging efficiency and protect the group from predators. At the edge of the woods, I also observed a flock of European Starlings and a flock of American Crows. Flocking behavior is important for generating warmth, particularly overnight, when both of these species are known to roost in trees in huge numbers. Smaller species like Chickadees, Nuthatches, and Woodpeckers typically spend nights in cavities and use their feathers as insulation.

Snags were difficult to find on campus due to landscaping, but I did observe a Black-capped Chickadee emerging from one small cavity in a deciduous tree. Conversely, Centennial Woods had an abundance of snags and cavities of all sizes. Many snags seemed to be too small to host cavity nesters, while large snags were often toppled and therefore also unusable. However, there were a few cavities that appeared suitable for both bird and small mammal residents. Although I knocked on several, I did not notice any activity inside. Perhaps if I returned and tried again at dusk, I would have better luck.

Start time: 12:22 pm
End time: 1:22 pm
Date: 2/4/2024
Locations: Woods and pond near Burlington Country Club, Redstone Campus, Redstone pines
Weather: Clear and sunny; 28-31 F, 8 mph south wind
Habitats:

1. Open pond with marshy vegetation
2. Smallish copse of mature deciduous trees, mostly Northern red oak; some deciduous understory as well
3. Copse of planted Eastern red cedars bordered by a fence. Paths and mowed fields on either side of trees
4. Mature Eastern white pines with very little understory besides a magnolia shrub. Some mature-to-intermediate deciduous trees nearby with more understory

For much of my walk, birds were somewhat few and far between. In the woods near the country club, I saw several Black-capped Chickadees, which I drew in my field notebook. Chickadees have high contrast markings (black cap and chinstrap) which made them easy to portray on paper. I saw a few other Black-capped Chickadees during the course of my walk, as well as many Dark-eyed Juncos and a Northern Cardinal seemingly foraging in a copse of planted Eastern red cedars. I saw no birds as I walked across Redstone campus from the country club to the pines.

Conversely, the end of my walk in the Redstone pines had an almost overwhelming number and variety of bird species. Their close proximity to each other made it easier to compare and contrast their flight patterns and wing shapes. I saw several Mourning Doves and noticed that their wings had a higher aspect ratio than most of the other birds I observed. They flew very swiftly, which makes me think their wings fall under the "high speed" category. They beat their wings powerfully and in an even pattern (i.e. beat-beat-beat).

Nearly every bird I saw on my walk was a species that I had encountered many times before, so I felt fairly confident in my identification. However, one bird's song was identified by the Merlin app as either a Ruby-crowned Kinglet or Pine Siskin, neither of which are birds I felt confident identifying. I observed the individual to the best of my ability and the main identifying characteristics are as follows: pale yellow-brown color, little contrast or identifiable markings from a distance, solitary, did not vocalize except for the one recording, and perched high on a deciduous tree. It was about 1/3 the size of the Mourning Doves and had more elliptical wings with noticeable gaps in the primaries during flight. It also had a more asymmetrical flapping pattern (beatbeatbeat-pause-beatbeatbeat). The Pine Siskin has a very streaky pattern, so I believe it can be ruled out as a possibility. Therefore, it was likely either a Ruby-crowned Kinglet or another species which I cannot identify.

Based on my experience today, I believe sunny weather increases the likelihood of encountering birds. Early afternoon seemed to be an adequate time to search, although I would like to try going earlier in the morning as well. Finally, the distribution of birds was seemingly focused around food sources like seeds and berries, particularly from evergreens.