April 26, 2021

Field Journal 7: Reproductive Ecology and Evolution

Start Time: 1:05pm End Time: 2:40pm Date: 04/025/21 Location: Centennial Woods, Burlington VT Weather: 30℉, rainy, and overcast. Habitat: Wooded area with waterways running through it. The woods had human footpaths, and a mix of coniferous trees, deciduous trees, and shrubs. Some behaviors that I observed related to nest selection was a female American Robin flitting around the branches of a coniferous tree, possibly inspecting different branch forks that would be ideal for building a nest in. I heard lots of American Robin calls, which I can assume to be territorial reminders. The American Robins that I observed are most likely nesting in evergreens because of how early in the season it is. American Robins have 2-3 clutches of eggs every year. The first clutch is often raised in evergreen trees because they offer the most protection as opposed to deciduous trees and shrubs that have not leafed out yet. I additionally saw a pair of Mallards, one male, and one female. They will probably be nesting on the bank of the small pond that I was walking by. Mallards prefer to nest in places with some cover, so most likely under a shrub or overhanging vegetation. Mallards have different habitat requirements (a body of water with sufficient food and vegetation on the bank) than an American Robin, who need leafy trees with forked branches to build their nests. Another species I observed was a House Sparrow, which generally prefers to nest in man-made structures or nest boxes. They also will nest in tree cavities. Additionally, American Crows prefer to nest in tall evergreens, and therefore need more middle/old-growth forest stands. A bird that I observed defending its territory was an American Robin. I believe it was defending a prime piece of territory because there were lots of evergreens, which they prefer to nest in during the colder months of spring. This indicated that this individual was pretty fit because it has to ward off any other robins who may be looking to steal or trespass on its territory. It probably had a sufficient source of food and shelter, and therefore could spend energy defending its territory. An American Robin builds its nest out of dead grass, twigs, and mud. While grass and twigs are the most common building materials, they also have been known to use feathers, roots, moss, and paper. The nest is built from the inside out. First, a cup of grass and twigs are formed, and then mud is added to the outside. Soft grass is then used to line the inside. American Robins have to go to wooded areas to find twigs and roots, and places with fields/meadows for grass. Additionally, mud can be acquired near waterways or in low-lying areas where water generally collects. Mini-Activity: For my mini activity I chose to sit by a stream on the edge of Centennial Woods. I heard 3 different bird calls in about 10 minutes. There was a lot of repetition. I think I heard an American Robin calling the most, along with periodic American Crow calls. There was another bird song that I believe to be a house sparrow, but it was so far away that I could not hear it as well. Overall the American Robin was the closest to me and stayed in the same area. The American Crows flew over me while calling to each other.
Posted on April 26, 2021 17:09 by elenarbernier elenarbernier | 4 observations | 0 comments | Leave a comment

April 19, 2021

Field Journal 6: Field Observation

Time: 1:30pm-3pm
Date: 04/17/21
Location: Winnoski River, Winooski VT
Weather: Overcast and about 45 degrees Fahrenheit.
Habitat: River going through a semi-urban area.

Note: I also saw an American Robin but was unable to get a picture of if so I did not list it as an observation.

Posted on April 19, 2021 21:06 by elenarbernier elenarbernier | 2 observations | 0 comments | Leave a comment

April 05, 2021

Field Journal 5: Migration

Start Time: 4:00pm
End Time: 5:30pm
Date: 04/04/21
Location: Trinity Woods, Burlington VT
Weather: 45℉ and sunny
Habitat: A couple of acres of woods in an urban area. There was a little valley made by two hills with old-growth pine trees. One thing to note was that this area gets a lot of noise pollution from the F-35 jets that fly over routinely.

On a bright, sunny Sunday I headed over to the woods behind Trinity to go birding. I saw a few American Crows, Ring-Billed Gulls, a Mourning Dove, two Rock Pigeons, and a Great Black-backed Gull. I was fairly surprised when I saw the Great Black-backed Gull because it looked like a crow with a white head! But upon further research afterwards, I was able to determine what species it was.

A year-round resident species that I observed was a couple of Rock Pigeons. They do not migrate because they are able to survive in cold temperatures and do not want to expend the huge amount of energy it takes to migrate. To keep warm Rock pigeons fluff up their feathers, creating air pockets around their bodies that insulate them. When they are sleeping they tuck their bills into their back, which helps to keep the heated air trapped around their body. Rock pigeons can also enter a state of torpor. In this state, barely any energy is used and their body temperature drops down to as low as 50 ℉.

A facultative migrant that I observed was a Mourning Dove. Mourning Doves who reside in the northern United States and southern Canada will fly thousands of miles south to Mexico. Individuals who breed in central and southern United States may only migrate a few hundred miles or not migrate at all. However, with warming climates and shorter winters, fewer Mourning Doves may opt to migrate every year. If this mourning Dove did opt to migrate this winter, I can assume that it was arriving in Burlington to either stay for the spring/summer or head more north into Canada. It could have come from as far as Southern Mexico! Mourning Doves migrate in the spring to partake in the breeding season. In addition, they migrate because their survival offsets mortality that would result from not migrating. Warmer weather and widespread new growth that comes with Spring facilitated its arrival to Burlington.

Mini Activity: total miles traveled by all migrants observed

Mourning Dove: 3,480 miles
Notes: Populations who spend the breeding season in the northern U.S. or Canada will fly as far as Southern Mexico for the winter. Populations in the central and southern U.S. may not migrate at all.

Ring-Billed Gull:
Total distance traveled: 1,300 miles
Notes: Ring-billed gulls tend to migrate along coasts and large rover systems. They spend the winter in the southern U.S.

Black-Backed Gull: 850 miles
Notes: Some populations in Massccutes and Nova Scotia stay year-round, while populations in Eastern Canada and Maine migrate south along the coast or to the Great Lakes region. This individual was probably passing through Burlington as it continued its migration to Canada.

Posted on April 05, 2021 17:29 by elenarbernier elenarbernier | 5 observations | 0 comments | Leave a comment

March 22, 2021

Field Journal 4: Social Behavior and Phenology

Start time: 12pm
End time: 2:45pm
Date: 03/18/21
Location: Lone Rock Point, Burlington VT
Weather: 29℉ and partially cloudy
Habitat: Semi-urban cliffs/wooded area on Lake Champlain, with a large beach nearby.

The Herring Gulls that I spotted were flying along the water. I ended up seeing five in total, but not all in a group. They flew mostly by themselves, and sometimes in pairs. I believe they were looking for food and were probably heading to the more populated beach area to scavenge. They did not seem to be interacting much as they flew. I also saw a pair of what I believe to be Common Mergansers. They were swimming in a pair so I can assume they were a mating pair. They stuck close together as they swam. In terms of visual cues, this pair of common mergansers definitely were indicating that they were focussed on each other and intended to swim together.

The Common Mergansers were definitely displaying their spring plumage, although I could not see them that clearly (they were very far away). The male most likely had his breeding plumage on display. This consists of a green head and a white body with black wings. A male Common Merganser’s non-breeding plumage resembles the females’ plumage - a brown head with a grayish body.

On the other hand, Herring Gulls do not have any significant changes in plumage year-round. There is also no difference in plumage between males and females. However, males are generally larger than females. One reason why Herring Gulls might not have a difference in plumage between males and females is because they are both very attentive parents. Usually, birds with more color variation between sexes generally have only the females take care of the young. This is because bright plumage may attract unwanted predators to the nest. Plumage that blends in better to the surrounding environment is better suited for taking care of young.

One of the Herring Gulls that I was observing was definitely foraging for food. It was skimming low over the water, in addition to heading in the direction of a populated beach. This makes sense due to the fact that it was the middle of the day. Even though the temperatures are generally increasing, it still gets pretty chilly during the evening and night. This gull is foraging for food during the day because it does not have to expend as much energy keeping warm, and therefore can use up more energy to find food. This circadian rhythm is enforced by the amount of daylight produced by the sun every day.

For the mini activity, I made a repeated “pshh” sound. This alters the behavior of small birds because it resembles a call that would be made by a fellow small bird. Birds want to know who is in their territory/habitat, so they are curious about the noise and are enticed to react to it.

Posted on March 22, 2021 04:53 by elenarbernier elenarbernier | 2 observations | 0 comments | Leave a comment

March 08, 2021

Field Journal 3: Ecological Physiology

Start time: 1:30pm
End time: 3:30pm
Date: 03/06/21
Location: Blueberry Lake, Warren VT
Weather: 19℉ and cloudy
Habitat: Trail system through coniferous forest surrounded by farm fields.

On a chilly Saturday afternoon, I headed down to Warren, Vermont to do some bird watching. The trail system that I explored was around Blueberry Lake, consisting of mostly coniferous trees as well as some open farm fields. I did not see a lot of birds that I was able to identify, which may be due to the high amount of loud families and dogs that were also there that day. However, I did see two American Crows and suspect that there were quite a bit more out of sight.

American Crows have evolved to be able to survive in pretty chilly temperatures in the winter. Some behavioral adaptations that crows display to keep warm consist of fluffing their feathers, tucking a leg or beak into its feathers, shivering, sunning, and roosting. Additionally, crows will sun themselves and go into a state called “torpor”. When in this state, they will lie on the ground with their bills open and go into a state of unconsciousness where their core temperature drops 10-12 degrees. Additionally, their heart rate and respiration are reduced which allows the bird to save 20% of its energy. This saved energy goes towards keeping the bird warm.

American crows are pretty omnivorous and will scavenge whatever they can find. The bulk of their diet in the spring and summer consists of earthworms and other terrestrial invertebrates. In the winter, they rely mostly on waste grain. This could be one of the reasons why I saw American Crows on my walk, because I was near lots of farm fields. American Crows budget their time in the winter to be awake and active during the warmest part of the day. In order to be in the sun the longest, they leave their roost sites at sunrise and hunt for food/sun themselves throughout the day. In the evening, they roost with other crows to conserve body heat during the night.

I believe that the crows that I was observing were beginning to look for a roosting place. Roosting is a behavior that crows exhibit where they gather in large flocks at night to conserve body heat. Because the temperature was already starting to drop so rapidly, and it was a pretty cloudy day, the crows that I was observing may have been beginning to do just that.

Snags are important in the winter because they provide shelter for birds and other wildlife to spend the night in. Sleeping in a cavity can trap body heat, and raise the body temperature of a bird. Some bird species that are likely to use them are smaller songbirds that need to rely on sheltered areas to maintain their body temperature At the end of my walk, I observed two cavities. One was larger with a few holes in it and had a good-sized cavity. The other had a smaller cavity, which I suspect a woodpecker made.

Posted on March 08, 2021 03:46 by elenarbernier elenarbernier | 1 observation | 0 comments | Leave a comment

February 22, 2021

Field Journal 2: ID and Flight Physiology

Date: 02/21/21
Start Time: 3:00pm
End Time: 5:00pm
Location: Trinity Woods
Weather: 24℉, little to no wind, sunny with no clouds/precipitation
Habitats: Secondary forest, behind urban area.

I decided to observe some Black-capped Chickadees in the woods behind Trinity campus. I really enjoyed watching the four chickadees that I saw flitting around from branch to branch. I would classify their flight pattern as slow flitting short flights with quick wing beats. By flitting, I mean that their flight was quite erratic and abrupt. Their wing type is elliptical. Another species that I observed for comparison was a House Sparrow. Their flight pattern could be described as a swift bounding flight, also with an elliptical wing. Their wing flaps are a few fast wing beats interrupted by gliding through the air with their wings pulled to the sides.

There is a relationship between wing shape, flight style, and habitat niche because the shape of a bird’s wing determines how it is able to fly. The different types of mobility that wing shape allows determines which habitats different birds are able to inhabit. Birds with smaller wings, like Black-capped Chickadees and House Sparrows, are able to maneuver better in the canopy and understory of a forest because there is less space to fly. In addition, their rapid wing beats and fast flight allows them to forage for food on the ground and fly up into the trees quickly in the event of a threat. Birds with longer wings are able to glide, and often can be found in more open spaces. For example, hawks and owls use their longer wings to glide through the air, searching for prey.

Using flight patterns to identify a Black-capped Chickadee could be useful because of their distinct flitting flight. If I saw a Black-capped Chickadee but wasn’t able to see any of its field marks, I could definitely be able to identify it by recognizing its flight pattern. Additionally, I could distinguish it from a House Sparrow, based on the fact that Black-capped Chickadees do not glide in between rapid wing beats.

Posted on February 22, 2021 03:35 by elenarbernier elenarbernier | 0 comments | Leave a comment