10 de abril de 2024

(Mini) Field Journal #5

Date: April 4, 2024
Time: 4:37 p.m.
Location: 44.4736652, -73.1941239
Weather: Snow
Habitat: Urban

There were about 10 American Robins and 4 Cedar Waxwings but I was only able to get one picture of each.

Publicado el abril 10, 2024 06:36 TARDE por noxgiordano noxgiordano | 2 observaciones | 0 comentarios | Deja un comentario

25 de marzo de 2024

Field Journal Entry #4

Date: March 25, 2024
Start time: 15:39
End time: 16:48
Location: Centennial Woods Natural Area (44.475362, -73.188345)

Temperature: 40°F
Wind speed/direction: 8 mph SE
Precipitation: 0”
Habitat(s): mature conifer stands, mixed hardwoods, fields, streams and wetlands

Species List:
Black-capped Chickadee (Poecile atricapillus)
Ring-billed Gull (​​Larus delawarensis)

Today’s fieldwork took place in Centennial Woods to consider different wintering strategies of birds found in Burlington, specifically their choice to migrate or not. When walking to Centennial, I heard the sound of a gull flying overhead and, upon closer inspection, I determined it to be a Ring-billed Gull (​​Larus delawarensis). Ring-billed Gulls are not resident species in Vermont and are considered obligate migrates due to the fact that they leave each year at around the same time, as if they are “hardwired” to do so despite outside influences such as a lack of food availability. Even if their food sources were available in winter, they would still be expected to migrate. This makes sense for Ring-billed Gulls because they are omnivores and eat bugs as a main part of their diet which would go away in winter and can be found more south and come back around April. As I entered Centennial Woods, I encountered a group of Black-capped chickadees (Poecile atricapillus). As usual, they were foraging in the brush and shrubbery that can be found all over Centennial Woods. These birds have a quite the contrasting wintering strategy to the Ring-billed Gulls. They are resident birds which means they stay in Vermont all-year-round. In order to survive the harsh Vermont winters, Black-capped chickadees undergo facultative hypothermia which is where they are able to purposely shut down their bodies enough to where they stay alive while having their metabolism as slow as possible. This may be just as dangerous as migration because if a predator found them in this state, they would not be able to fight back and it takes several hours for them to be back to normal. Additionally, this is why tree cavities are very important to resident birds such as the Black-capped chickadee because they provide shelter.
Ring-billed gulls spend the winter months in the southern United States. If they are going all the way to the tip of Florida and back again, that would be about 3,450 miles round trip!

Publicado el marzo 25, 2024 10:29 TARDE por noxgiordano noxgiordano | 6 observaciones | 0 comentarios | Deja un comentario

09 de marzo de 2024

Field Journal Entry #3

Field Journal Entry #3

Date: March 8, 2024
Start time: 15:43
End time: 16:51
Location: Centennial Woods Natural Area (44.475362, -73.188345)

Temperature: 45°F
Wind speed/direction: 4 mph N
Precipitation: 0”
Habitat(s): mature conifer stands, mixed hardwoods, fields, streams and wetlands

Species List:
Black-capped chickadee (Poecile atricapillus)
American crow (Corvus brachyrhynchos)

Today’s fieldwork took place in Centennial Woods to observe some of the ways birds communicate and interact with one another. At the entrance, I ran into a familiar flock of Black-capped chickadees (Poecile atricapillus) that I had run into the week before. I noticed that they were foraging, picking whatever berries, seeds, or buds were left on the bush-like foliage. Moving like this would probably generate more heat than sitting still while the looked for more food for caloric intake. I was a little frustrated at first because it seemed to me at first that they weren’t interacting with each other which is what I needed them to do for this field journal. However, not too long after, I heard the call of an American crow (Corvus brachyrhynchos) and that’s when I realized that they were communicating the whole time - the little chirps and whistles they were doing beforehand and, of course, the recognizable alarm call once the crow came into play, It was interesting to think about because, as a human, I would have assumed that they were acting as individuals. Still, by vocalizing, they were communicating to each other and other birds in the area about perhaps territory or potential threats. When thinking about the plumage of these two species, they contrast quite greatly. The black plumage of the American crow is very recognizable. I usually see crows flying large distances rather than hopping around foraging like the chickadee. The black feathers would be advantageous to them because melanin strengthens their feathers so they are able to fly farther distances than resident songbirds like the chickadee. In comparison, the chickadee’s plumage is much thicker than the crow’s, providing more insulation during the harsh Vermont winters. Their gray, tan, white and black plumage may provide some degree of camouflage as these birds spend a lot of time foraging or in the cavities of stags. I did try the “spishing” but I think I may have been doing it wrong because all it did for me was scare the birds that I was observing away. If done correctly, maybe this mimics the call of other songbirds similar to the “Magic Tape” used to lure curious chickadees to a mist net.

Publicado el marzo 9, 2024 03:45 MAÑANA por noxgiordano noxgiordano | 6 observaciones | 1 comentario | Deja un comentario

26 de febrero de 2024

Field Journal Entry #2

Date: February 23, 2024
Start time: 15:54
End time: 17:03
Location: Centennial Woods Natural Area (44.475362, -73.188345)

Temperature: 46°F
Wind speed/direction: 10 mph SSW
Precipitation: 0”
Habitat(s): mature conifer stands, mixed hardwoods, fields, streams and wetlands

Species List:
Black-capped chickadee (Poecile atricapillus)
Dark-eyed junco (Junco hyemalis)

Today’s fieldwork took place at Centennial Woods Natural Area to observe some of the strategies resident birds use to survive the harsh Vermont winters. The first species I encountered was a group of Black-capped chickadees (Poecile atricapillus) at the entrance as well as two Dark-eyed juncos (Junco hyemalis). This did not surprise me because chickadees and juncos are both typically found in groups and prefer edges of forests. As I observed their behavior, I noticed that they were foraging in a shrub of some sort. Upon closer inspection of the shrub, it seemed to be some sort of juvenile ash intertwined with a species of Rubus. It would make sense that the chickadees were hanging around here because these two species of trees are important food sources for wintering birds as they provide seeds, berries (if there are any left), and shelter for small birds such as chickadees and juncos. They also may be eating the buds off of these trees. In the winter, these birds must not be getting much protein because the insects that usually reside in the bark of ash trees have all died by now. This shrub also provided the birds shelter both from predators and the harsh winter winds.
Not much further into the woods, I stumbled upon a snag with many cavities. This must be like a condo or an apartment to birds because there were so many places to choose to spend overnight. The cavities were relatively small, the perfect size for a junco or chickadee, so I think it is safe to say this is where these birds may be storing food or sleeping overnight. Snags are essential to resident bird survival in Vermont winters. Black-capped chickadees have a unique strategy to conserve energy and body heat during winter called facultative hypothermia which, in the simplest terms, is hypothermia on purpose. These birds are able to lower their metabolism to the point of hypothermia in order to survive on very low energy reserves. If their metabolism gets low enough, they enter what is called torpor. Torpor is the most extreme form of facultative hypothermia and leaves the birds very vulnerable to predators because they are unable to rouse or function normally. This is why snags are so important to resident birds in winter because it allows them to conserve energy in a safe place from predators.

Publicado el febrero 26, 2024 07:04 TARDE por noxgiordano noxgiordano | 4 observaciones | 0 comentarios | Deja un comentario

10 de febrero de 2024

Field Journal Entry #1

Date: February 9, 2024
Start time: 14:37
End time: 15:53
Location: Williams Woods Natural Area (44.270207, -73.251739)
Temperature: 49°F
Wind speed/direction: 12 mph S
Precipitation: 0”
Habitat(s): mature, valley clayplain forest

Species List:
American crow (Corvus brachyrhynchos)
American robin (Turdus migratorius)
Black-capped chickadee (Poecile atricapillus)
Pileated woodpecker (Dryocopus pileatus)

Today’s fieldwork took place at Williams Wood Nature Preserve to observe the flight patterns of different birds relative to their wing shape, flight style, and habitat niche. The first species of bird I encountered was the American crow (Corvus brachyrhynchos). I heard them before I saw them and looked up to see four flying together. Their flight pattern was decently straightforward with minimal dips and many flaps. They occasionally glided but not for very long before returning to the rhythmic beating of their wings. The distinctive “caw” and fan-shaped tail were clear identifiers but the flight pattern helped solidify any doubts of confusing them with the common raven (Corvus corax). Watching them fly reminded me of the saying “as the crow flies” which refers to the shortest path to take to get from point A to point B, and it was clear to me why people say that - their flight pattern is the most direct route with no dips to slow them down.
In contrast, the second species I identified was the American robin (Turdus migratorius) which had a much more erratic flight pattern compared to the American crow. Again, I heard the bird before I saw it and observed as it quickly fluttered from one tree to another. In the split second that I was able to see its flight pattern, the difference between the two species was like night and day. There was much more flapping involved in the robin’s flight and, unlike the crow, had dips where it would tuck its wings in (presumably to minimize drag and ride on momentum) before spreading their wings once again to allow the lift to keep them airborne. Honorable mentions of birds that I briefly heard but did not see were the Black-capped chickadee (Poecile atricapillus) and a pileated woodpecker (Dryocopus pileatus).
I think a major factor in the difference between the flight patterns is their wing shape. The wing shapes are directly correlated to their ecological niche and environmental needs. The robin has a pointed, elliptical wing shape which allows them to take off quickly but consequently does not allow lift to hold for very long. This is perfect for flitting between trees and branches while also being capable of migration. Unlike the American robin, the American crow has slotted, high-lift wings with long primaries that allow them to achieve more lift and look more leisurely. This is because their main purpose for flying is not to migrate or hunt but to get from one place to another, usually to roost. There were not many birds during my fieldwork which I think is because it was too late in the day for many birds to be flying around. I also think the lack of birds is attributed to the fact that there were many planes overhead as well as a train right next to a road so the birds probably didn’t want to hang around so much human activity. Next time, I will go to a more secluded area preferably in the early morning.

Publicado el febrero 10, 2024 01:24 MAÑANA por noxgiordano noxgiordano | 7 observaciones | 0 comentarios | Deja un comentario