11 de mayo de 2023

Field Journal 8

May 5, 2023
Start time: 7:30 PM
End time: 8:45 PM
Location: North Beach/Rock Point, Burlington VT
Weather: cool 50s, slight breeze, overcast
Habitats: lakeshore, spruce tree crowns, thickets near ground, general forest patches, open field

Publicado el mayo 11, 2023 04:03 MAÑANA por evostal evostal | 4 observaciones | 0 comentarios | Deja un comentario

01 de mayo de 2023

Field Journal 7

April 21, 2023
Start time: 5:45 AM
End time: 7:10 AM
Location: Centennial Woods, Burlington, VT
Weather: overcast, chilly 40s, light breeze, misting/lightly raining
Habitats: edge, open fields, near water, mixed forest

I set out early one Friday morning to gather point count data for NR 103. While I was dreading getting up early, an early morning walk through the woods proved very beneficial for myself. Listening to the birds during peak migration during dawn chorus was definitely the right way to start a dreary Friday morning. I heard 20+ species and was able to identify most of them without any help from Merlin, which made me very excited and proud of the ID abilities I've picked up in this class.

The behaviors I witnessed that morning were clearly attempts at mate selection. Not many birds were seen nesting (or seen at all), but the majority of birds were male birds singing and calling for mates. I saw a Northern Cardinal perched high on a tree that had yet to leaf out. Its bright red feathers stood out against the gray-brown backdrop and it was clear that he knew he was easy to locate. Waiting for other calls to die down, he would let out his jarring car-alarm-like call. This tree was prime territory for the Cardinal, as they prefer tall trees on the edge of habitats as opposed to denser, wooded areas. It was also surrounded by thickets on either side, offering him and his soon-to-be-mate shelter lower to the ground. This may show that he is ready and fit for mating season.

In Centennial Woods, birds nest everywhere. From Chickadees at the edges of parking lots, to American Robin at the beaver pond, to the Barred Owl pair in the tall evergreen trees. Based on habitat and nutritional requirements, habitat location varies greatly among species. For example, Ruby-crowned Kinglet need a place where the can easily find bugs to eat so open fields and tall evergreens are ideal for them. American Crows on the other hand are generalists which can be found anywhere, eating almost anything (worms, berries, snakes, trash, etc).

Carolina Wren are very resourceful nest builders. While they prefer a cavity, they don't need it to be in a tree. Carolina Wren nests can be found in snags, upturned trees, mailboxes, and even old boots left outside. They use twigs, hair, weeds, moss, and feathers to build their nest which are all readily available within a short commute in Centennial.

Publicado el mayo 1, 2023 01:04 MAÑANA por evostal evostal | 22 observaciones | 0 comentarios | Deja un comentario

19 de abril de 2023

Field Journal 6

April 16, 2023
Start time: 8:10 AM
End time: 9:30 AM
Location: Burlington Country Club Golf Course, Burlington, VT
Weather: sunny, bluebird sky, 70s, light breeze
Habitats: suburban edge, open fields, pine trees

Publicado el abril 19, 2023 03:54 MAÑANA por evostal evostal | 6 observaciones | 0 comentarios | Deja un comentario

30 de marzo de 2023

Journal 5

March 29, 2023
Start time: 10:50 AM
End time: 12:05 PM
Location: Centennial Woods, Burlington, VT
Weather: sunny, few clouds, low 40s, light breeze
Habitats: suburban edge, deciduous woods, creek area, some open patches/edges

In Centennial Woods today, many year-round species were seen, and one migratory species: Ring-billed Gull. On the forest edge, walking in, I saw American Robins, a very vocal Tufted Titmouse, and some Black-capped Chickadee. American Robins can survive Vermont winters because of their adaptations, though most migrate for the winter. They fluff up their feathers to create space and insulation under their down feathers that keeps their core temperature at 104° F. This is really only effective as long as they stay sheltered and dry. Their feet do not get cold because of countercurrent exchange: blood flowing to the feet warms blood flowing from the feet. In the warmer months, American Robins cool off by submerging themselves in water and, similarly to winter time, fluff up their feathers, but more so this time in hopes of catching a breeze across their skin. Tufted Titmice follow similar adaptations, but also increase the frequency of feeding to keep their bodies warm in the winter.

Unlike American Robin and Tufted Titmouse, Black-capped Chickadees utilize facultative hypothermia to endure the winter months. Facultative hypothermia allows for birds to drop their metabolic rates at night so that energy is saved for when they need it. Black-Capped Chickadees' body temperature 18° F from 104° to 86° F. Also, BCCH that live at higher latitudes are much larger than those more southerly chickadees to allow for more fat to be on the body to store more heat. This is a clear example of a physiological (and regional) adaptation. Carolina Wren, on the other hand, lack this feature and utilize sheltered or indoor roosting sites to stay warm. They even share roost sites with other wrens.

The one true migrant observed was the Ring-billed Gull. RBGU breed north of Vermont near the Hudson Bay, and across the country in all southern provinces, as well as north-western states in the US. In the winter, east coast gulls migrate to the coast from Massachusetts south to the Caribbean. Those in Burlington most likely migrate to Massachusetts beaches for the winter and the St. Lawrence River and Gulf for spring breeding. Burlington has begun to warm for the spring, welcoming in migrants like the Ring-billed Gull. Lake Champlain having melted also probably facilitates the arrival of RBGU because they are coastal birds largely, or at least spend time on shores near water.

Publicado el marzo 30, 2023 03:22 MAÑANA por evostal evostal | 10 observaciones | 0 comentarios | Deja un comentario

19 de marzo de 2023

Field Journal 4

March 17, 2023
Start time: 12:15 PM
End time: 2:30 PM
Location: Malibu Creek State Park, CA
Weather: sunny, no clouds, low 60s, light breeze, mid humidity around 50%
Habitats: large creek bed, mountains, valleys, wildflowers, fire-resistant vegetation: Redwoods, chaparral, arroyo willow, and California bay laurel

At Malibu Creek State Park there was an abundance of bird species as springtime has started to emerge in all forms. The superbloom has just started in southern California - a time when wildflowers (especially poppies) begin to bloom, and coincides with the very beginning of migration season for birds. Many hawks and birds with high slotted wings were seen overhead circling, sometimes in groups of up to 10. They were too high in sky to determine their species, but in close-up pictures slotted primary feathers were clear. This group circling occurs so that they can stay on the thermals and continue to soar without having to use energy flapping. Other birds were very loud and communicative through calls and songs. As March is the start of migration season, this calling may have been an attempt to gather birds together to migrate in a large group.

The plumage between two woodpeckers observed share some traits but look vastly different. Acorn Woodpeckers have a red crest, white eyes, black bill, back, wings, and breast, white throat and stomach, and a black and white face. Their red crest may prevent this species from being preyed on as red is often a threatening or dangerous color in the animal kingdom. Their black and white bodies allow them to get lost in tree bark as a well as the sky when looking at them. On the other hand, Lewis's Woodpeckers have a red/pink breast, stomach, and face, shiny green back and wings that looked blue in my observation, a black beak and cap, and a grayish throat. Their shiny back and feathers obscure wavelengths and cause their wings and back to have different colors depending on the angle and light under which they are being observed, and when it does look green, it is a similar green to trees and grasses. This can be confusing for possible predators, so it may be an adaptation against predation from above. Their plumage color pallet reflects that of the Ponderosa pines in which they usually find a home. This likely allows them to camouflage into these trees so they can catch flying bugs with stealth (they are a flycatcher despite having woodpecker in the name). These woodpeckers both have plumage to keep them hidden yet are vastly different in coloration.

The Double-crested Cormorant was observed standing on a sandbar in the creek then swimming downstream. Alone, this Cormorant seemed to be resting. Malibu Creek State Park is an interesting location for the Double-breasted Cormorant, as the Santa Monica mountains are described as being non-breeding grounds and migration locations for this fowl (All About Birds). This bird may have been resting up before starting its migration to the northern US or southern Canada for breeding season, or it could've been resting early into its migration to its summer home.

Spishing was not very effective on many birds in Malibu Creek. Many were waterfowl who did not seem to care at all, woodpeckers stopped for a moment then flew off or continued their activities, and the smaller song birds seen quickly ran off the path. Some spishing made some wrens and sparrows stop and stare for a while but no birds ended up nearer because of this action. Wrens and sparrows would stop in the underbrush or on branches to listen to the spishing, but no reactions were exactly had.

Publicado el marzo 19, 2023 01:15 MAÑANA por evostal evostal | 10 observaciones | 0 comentarios | Deja un comentario

03 de marzo de 2023

Field Journal 2

March 2, 2023
Start time: 1:45 PM
End time: 2:45 PM
Location: North Beach/Rock Point, Burlington VT
Weather: mid 30°s, mix of rain and snow, coming down at a medium pace, windy by the lake but calm in the woods and beyond
Habitats: lakeshore, spruce tree crowns, thickets near ground, general forest patches, open field
I started this bird walk with very low hopes. It was a mix of rain and snow, and I had not heard anything on campus all day. But the beach and Rock Point were abundant with species! Mallards, Black Ducks, a Common Goldeneye, and some Mergansers could be seen from the shore of Lake Champlain. Mallards were eating leaf litter that had become revealed by the melted snow. Mallards eat plant material, which is sparser in winter, so I assume leaf litter is something they settle for in the colder months to get energy. Mergansers were further from the shore, ducking under the water for their food unlike the Mallard. With the lake no longer being frozen, I would assume it is easier for Mergansers to get fish for their energy. Other than food, ducks stay warm using their down feathers. Their preen gland produces and oil that ducks spread over their outer feathers to waterproof them. This prevents the down from getting wet, and keeps them warm.
A Rough-legged Hawk was also spotted circling above the lake close to shore. According to e-bird, there hasn't been a siting at North Beach in 10 years, and there are none recorded in the direct vicinity on iNaturalist. This was really exciting for me, and it was the first time I've been very excited about observing and seeing a specific bird species. This Rough-legged was seen just soaring and circling overhead. There was no clear action the hawk was doing that signaled it was keeping warm. With lake not being frozen, the hawk may have been looking for smaller mammals near the lake shore since they do not catch/eat fish, unless they do eat fish in the winter when smaller rodents are harder to find in snow covered fields.
Many of the other birds heard nearer Rock Point were resting in trees, and very few were seen in flight. Black-capped Chickadees, White-breasted Nuthatch, and a Carolina Wren were heard in a patch of forest, with the Carolina Wren calling loudly from a tall and thick spruce tree. These smaller birds were resting which seems to be how they were staying warm on this rainy and cold winter's day. At night, these birds most likely find a tree cavity or thick underbrush to stay warm in. No cavities were observed to be actively housing anything this day.

There were not many snags or cavities in sight in the woods at Rock Point, but the one that was knocked on showed no sign of critters holing up inside. Snags are important for many different species including birds (specifically owls), squirrels, raccoons, and fisher cat. Cavities are likely larger in larger snags, and the larger the cavity, the larger the animal it can host.

Publicado el marzo 3, 2023 02:51 MAÑANA por evostal evostal | 12 observaciones | 0 comentarios | Deja un comentario

22 de febrero de 2023

Field Journal 1

7:15 AM - 8:15 AM
February 21, 2023
UVM Bike Path
around 20° F, sunny
habitat: segmented corridor flanked by a major road and a golf course

The main species I observed were American Crows. They are abundant in Burlington, and I have grown to enjoy watching them from my dorm window (see linked photo and audio). Their nature is quite funny to be completely honest. Their various calls and sounds are amusing and the way the hop along the ground occasionally is a source of humor for me. It is no surprise I saw crows here, since they tend to hang out near roadsides and fields. Though, their habitat is not narrow, crows are comfortable making a home in any tree, anywhere.
When landing, crows lead with their feet, and almost float down to the ground before giving some big strokes a few times to create a controlled landing. Their bodies almost seemed a little out of synch from the wings, like the had to control their torsos from swinging for the landing to work. Crows also hop along the ground a lot, and I observed some interesting preening as well.
2 Ring-billed Gulls flew overhead - no surprise in Burlington - and I saw a third later one. Their flight was surprisingly similar to the crows. Their wings are extremely different, but in the moments I watched them, they flapped their long soaring wings multiple times before gliding for a short period. Crows seemed to follow the same pattern. When taking off from trees, they flap continuously until they are sustained in the air, and then glide for a very short period. Though they kind of follow a similar pattern, Ring-billed Gulls and American Crows look very different in flight. Gulls have the high aspect ratio wing of a soaring bird while crows have a more high speed wing, causing them to need to flap their wings quicker and more often, but still allowing them to glide.

Publicado el febrero 22, 2023 02:05 TARDE por evostal evostal | 4 observaciones | 0 comentarios | Deja un comentario

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