rwhennes's Journal

On Wednesday, May 2nd I rode my bike out to the Colchester Causeway to see how the bird population composition had changed since I had last been there. The last time I went out was an unusually warm day in February, and the lake was still mostly covered in ice. This time the lake was totally thawed and it was quite warm. I saw a handful of Ring-billed gulls flying together, as well as a couple Double-crested cormorants. What I was most excited to see however were the tiny, very fast birds I remembered seeing last summer but had been unable to identify at the time. I came across them swooping around a portion of the causeway that had frequent trees lining either side. From the shape I could see they were clearly swallows, though it took some careful observation to spot the distinctive red bib indicating that they were Barn Swallows. Last time I was here I saw a good deal of Common Mergansers and Common Goldeneyes, this time I only saw three Common Mergansers (two males and a female floating and diving relatively close to each other).

On the way back I stopped off at two more locations. First, I stopped by the marsh near Airplane Park. I had trouble actually spotting any birds through the thick marsh reeds and other foliage, but I certainly heard a lot. The distinctive marshy call of the Red-winged Blackbird certainly stood out, though I also heard Eastern Phoebes, Black-capped Chickadees, American Robins, House and Song Sparrows, Northern Cardinals and Blue Jays. The second place I stopped was just before the bridge back over the Colchester border back into Burlington. Here I heard more Red-winged Blackbirds and saw more Barn Swallows. What spurred me to stop however was spotting a Wood Duck paddling in the swamp below the bridge. I don’t think I’ve ever seen one in the wild before so it was an exciting find.

Today at around 2 pm I went with a couple classmates down too the Burlington Country Club to observe birds in the surrounding woody areas. It was cloudy and relatively cold, but the snow had stopped by then. We saw a handful of Common Grackles on our way down, in groups of 3-5, mostly in trees outside houses or by the road. Once at the country club, we explored two sections of woods fragment. The trees here were relatively dense but close to the road. We spotted an American Robin in the grass outside the first fragment. Inside the fragment we found a small clearing, where we spotted a handful of Black-capped Chickadees moving about in the upper parts of the surrounding trees. They were quite talkative. I also spotted a Red-breasted Nuthatch a bit further into the woods, and a Downy Woodpecker circling branches of a tree near the green.
In the second fragment, we found more chickadees. We also heard a bird call that we couldn't identify, it made a sound like a Brown-headed Cowbird immediately followed by part of a chickadee call, it repeated enough times that we didn't think it was coming from two separate birds. We thought it might be some sort of mocking bird, but we were unable to spot it for more than a moment and couldn’t identify it. A bit deeper into the woods, Carly found a large clump of long black feathers. They appeared to be from the tip of an American Crow's wing, though we weren't sure because the feathers weren't pure dark black, they appeared slightly brownish. They were the right size to be American Crow primary feathers. After this I had to leave for a meeting. I saw several more Common Grackles in trees along the sidewalk on my walk back, and saw several instances of pairs of Common Grackles with one pursuing the other.
EDIT: This was written on the 20th of April, but not posted until today, thus "Today" refers to Friday, April 20th.

1. On April 4th I went down to Lake Champlain to explore some small, fragmented woody areas near the Echo center. I also looked for birds in the bushes around a grassy park. The most striking birds I spotted were a large flock of Common Grackles in one of the small wooded areas. There was a group of at least 20 of them, though they tended to fly away too quickly for me to get a good picture of more than a couple at a time. According to All About Birds, our location is just barely on the border between their year-round and migratory summer breeding range. These birds are loose colonial nesters, though to my understanding do not necessarily flock unless they are migrating, and wintering colonies/foraging groups tend to be mixed flocks of different blackbird species. From this I assume that this group was a collection of short distant migrants. According to Birds of North America, Common Grackles that breed at latitudes of 44-45 degrees N tend to migrate about 1000 km, assuming that their path is direct and primarily from South to North, that would put this groups wintering location at somewhere around North Carolina, well within their year round range. As for why some Common Grackles migrate, while others from the same area may not may be due to resource competition. As more northern areas come in to spring, new untapped resources come into season, and moving into these areas would mean less competition from others during the breeding season. Grackles from even more southern populations such as those along the Gulf Coast generally are wholly non-migratory, likely due to a considerably higher abundance of resources available year round.

Another migratory bird I saw a handful of were American Robins. Here in Burlington, we are well within the year round range of these birds, and I have seen them throughout the winter, though they do certainly seem to be more common lately. According to Birds of North America, most American Robins migrate 500-1200 km between winter and summer ranges, though reduction in migratory distance to as little as 100 km has been more and more frequently observed as a result of climate change. In any case, it is relatively uncommon for the American Robin to overwinter in this part of Vermont, and assuming that these individuals are of the median standard migratory distance, that would put their wintering location somewhere around Maryland. Robins are ground feeders, relying heavily on soft bodied insects that would mostly be inaccessible in the frozen grounds of a Vermont winter, and like the Common Grackle likely migrate to evade competition from other birds and take advantage of newly accessible resources farther north.

On March 22nd, I arrived to one of my classes early and noticed several Cedar Waxwings and American Robins eating red berries off of a few trees just out the window. They mostly ignored each other, though the robins from time to time would chase off the smaller waxwings. Within the individual species, multiple waxwings would sometimes feed from the same branch, and robins were more likely to sit near other robins. The waxwings would also frequently hang upside down or at an odd angle from smaller branches in order to reach berries. There was minimal conflict between individuals of the same species, likely because the berries were relativley plentiful and breeding season is still a few weeks off at least for both species. Most conflict was resolved quickly, with the "aggressor" simply landing very close to a smaller bird and causing the smaller bird to fall off or fly away.

In terms of plummage, both male and female American Robins had their signature red breast. While not as bright as say a Northern Cardinal, it is distinct and unique, and likely used for intraspecific species recognition. Females and immature individuals may be slightly paler, though the contrast is often relativley minor. From my vantage point I wasn't really able to differentiate. Cedar Waxwings likewise have minimal sexual dimorphism, and all the ones I saw had adult plumage. They're easily recognizable by their black eyes and small crest.

Later that evening I came across a group of American Crows roosting together in a tree. There was minimal calling and some individuals came and left but of the lone crows I spotted most of them did touch down in the tree. This leads me to believe that this tree is regularly used or that grouping is determined by one individual seeing where others have already begun to congregate. One in the tree interaction between individuals was minimal.

Mini activity: I didn't manage to find any groups of chickadees, but on the 21st I took a ride on the bike path stopping occasionally to explore wooded areas and look for birds. I heard several chickadees but was only able to spot a few individuals. Of those individuals, one did seem to come a bit closer in response to my "pshh"-ing, though I think it may have just been passing by me on its way to get somewhere else. The sound had no effect on the others.

Back on February 28 the weather was nice so I decided to ride my bike from Oakridge Park to the Causeway. This journal is based on notes I took on that day. I started my ride at around noon and got home at around 3:30 pm. There was still a good deal of snow but the weather was sunny and the tempurature was in the mid 50s. Before beginning my ride I walked around the wooded areas of Oakridge Park to see if I could find any birds and investigate dead snags. I didn't end up seeing many birds in the park other than a few house sparrows and one blue jay, and drumming on snags didn't reveal any hidden birds. I spotted several squirrel nests but was unable to identify any bird nests.

Over the course of my ride I heard calls from blue jays, northern cardinals, house finches, house sparrows and robins. The trip became really interesting though once I made it to the Causeway. Riding out over the lake I ran into a friend who was out with a bird watching group, and she pointed out a snowy owl resting on the ice on the eastern side of the causeway, and lent me her binoculars. It had its feathers puffed up for warmth but was sadly too far away to get a good picture of. I also saw a large flock of common goldeneyes floating about 40 ft off the west side of the causeway near a sandy shore. It's interesting to note that the lake to the west of the Causeway was mostly melted, while the east side was still mostly covered in a layer of ice. The goldeneyes floated and dove where the ice had melted, while the snowy owl peered around and rested on the frozen portion of the lake.

By the time I was heading back the sun had started to set and it was getting a good deal cooler. I came off the Causeway and into a portion of path surrounded by woodland to the west and a frozen swamp to the east. Here I came across 3 American robins. They sang to one another and seemed to be a cohesive group, never straying to far apart as they moved from tree to tree down the path, avoiding me.

I am covering two separate birding excersions as I only managed to actually see a single bird during my first one. I would've liked to do my second walk earlier but I was sick for most of this week.

On February 9th I participated in a WFB 130 bird walk with TAs Alex and Danielle. We met at Aiken at 8 am and walked to the patch of pine trees near the UVM Interfaith Center. It was very cold and there was a good deal of snow on the ground. We could hear lots of birds, notably calls from the Northern Cardinal, American Crow, and Black-capped Chickadee. Of these, the only bird we actually spotted was a single Black-capped Chickadee flitting between two pine trees. It's flight style seemed to be short bursts of fast flaps followed by short, steep descent glides or parabolas.
We then moved further down the path to a second larger thicket of pines closer to Redstone campus. These pines were much taller and many lacked any lower branches, most starting at least 15 feet above the ground. We continued to hear calls from the aformentioned species, as well as that of a Blue Jay. We spotted several squirrel nests but no birds. This area borders some residential property, and we noticed a couple of bird feeders hung in the yards though they were not visited during the time we were there. After about an hour we decided to go back inside.

My second excursion was on February 16th, I was still feeling a bit under the weather but I had some errands to run down by the UMall and I knew that there was some wooded area near there, as well as American Crows and Rock Pigeons that hung around the mall parking lot. I got to the location a little after 3 pm. The weather wasn't great, it was snowing heavily for a while and I didn't see many birds. Once I ran my errands however the sky had cleared up and I saw, as expected, several small flocks of Rock Pigeons and American Crows. The crows were generally solitary, and when they did group together they didn't seem to coordinate their movement in any meaningful way. They tended towards even, powerful flaps with minimal gliding unless heading directly into the wind. Their wings were broad and roughly even in width from base to tip, the primaries splayed out widely, giving an appearence of fingers. The Rock Pigeons on the other hand formed cohesive groups of between 7 and 12 indivuduals. They flapped relativley infrequently, spending most of their time gliding. Their wings had a more streamlined shape than the crows, with less visible separation between the primary feathers. The nearby wooded areas prooved to be relativley barren in terms of bird activity at the time, possibly due to the intermittent snow and rain.