Field journal 4 - Social Behavior and Phenology

I went to the Salmon Hole in Winooski yesterday at about 5 PM. I parked in the lot and walked the short distance to the trail and continued down the trail until I reached an area that was surrounded on one side by the Winooski river, and the other side by trees. In the main spot where I decided to plant myself and look for birds there was a large deciduous tree on my right side that was growing on the edge of the river and some scattered vine-like brush beside it. To my left, there was a small hill where houses and restaurants sat at the top and trees covered the hillside. It was about 38 degrees, and very sunny with some sparse clouds floating in the sky. Although it was rather cold, the sunlight and absence of wind made it feel much warmer.
The two main birds that I saw interacting were the House Sparrows and the Black-capped Chickadees. The House Sparrows interacted mainly with each other through calls. In the tree ahead of me, there were about 4 of them sitting near each other on separate branches at the top of the canopy. It sounded like when one bird would sing a call and finish, then another one would begin to call. It was difficult to tell if these back and forth calls were just one bird or multiple, but I believe it was coming from multiple birds as a way of communication. The birds seemed to all be looking down at me from the tree so my assumption is that they were making calls to alert other birds that something was in their territory. I did not see much visual communication happening between the birds, but I also was not sure what to be looking for. I saw the House Sparrows fluttering their tails and poking their beaks into the bark of the tree, but none of them got very close to each other.
The House Sparrows were a little far away, and I did not have binoculars, so it was a little difficult to discern the exact color patterns. However, they had dark beaks, a light brown cap, and a white underbelly. Their wings appear to have a pattern that is black and orangish-tan, a pattern that reminds me of tiger stripes. Overall, the House Sparrows are dark birds. I would assume this is a type of cryptic coloration that allows them to blend in with trees, brush, and dark surfaces. This would be an advantage over predators that are unable to see them against these habitats and would allow them to not be eaten. On the other hand, the Black-capped Chickadees had dark black caps, with white patches stemming from their beaks. Their wings were black and white, and their bellies were a tannish-white color. The black and white contrast of the Chickadee does not seem beneficial for blending into a wooded environment. This leads me to believe that their plumage is a type of countershading; dark on the cap and the back, and white on the belly. This would be beneficial to protect themselves from predators that are flying above, and energy-saving by the whites of their bellies reflecting color off of their surroundings.
I focused on one particular Black-capped Chickadee that was resting in a viney-plant beside me. It was sitting there for a long time, seemingly doing nothing but staring into space. The sun was beginning to set at this point, so I assume it was about the point in the day when the bird was winding down and becoming less active. It's possible this bird was experiencing the part in its circadian rhythm where it was working on slowing down its metabolism and saving energy to prepare for activity later in the night. I decided to make some "pssh" noises at this Chickadee to see what kind of reaction it would have. At first, I made the noise at a normal pitch. The bird did not have any reaction and still just sat in the vines. After trying it at a more high-pitched level a few times, the bird eventually flew away. However, I was making advances at it at this point and getting closer to it which could be the reason that it ended up flying away. In this case, the noise did not seem to be enticing to this bird. However, I would assume that birds are generally enticed by this sound because it sounds like it could be a new kind of bird that is entering their territory and they want to figure out where the noise is coming form. In my opinion, it seems like the noise would gives rise to a fight reaction from the small birds.

Publicado el marzo 25, 2020 04:29 TARDE por g_underhill