FJ 7- Field Observation: Reproductive Ecology and Evolution
On Monday evening, April 20, from around 5-8 pm, with a long pause in my observing mid-way through, I went on another observation walk around my neighborhood in Belmont, Massachusetts. The weather was about 50 degrees Fahrenheit and sunny. My observations began from inside of my house.
I noticed a Red-bellied Woodpecker on the side of an Oak tree on my street. This oak tree, as I observed last week, seems to already be the home of two nesting Downy Woodpeckers. They were quite upset that this Red-bellied Woodpecker was trying to infringe on their nesting area, and put up a long fight that lasted for about an hour before they gave up. They were calling loudly and diving at the intruder. However, the Red-bellied Woodpecker was mostly unbothered and still remains on the oak tree, creating what I assume is a nesting cavity. I assume this because the cavity it is creating is very large and it has been working on the same spot for multiple days now. It is also between March and May, which is when Red-bellied Woodpeckers nest. However, upon research, it seems that normally a pair of woodpeckers work together in creating their nest (allaboutbirds.org). It is possible I have not noticed a second one, but it seems there is only one woodpecker, which may mean that it is not nesting. I am going to try and ID the gender of the bird and continue to observe and see if another gender arrives in the next few days.
The Downy Woodpeckers were defending their prime territory on my street. There are a lot of decaying branches and trees, as well as many cavities that are the perfect environment for Woodpeckers. There are many other Downy Woodpeckers that live in the area, but I believe the two that attacked the Red-bellied Woodpecker are the only ones that live on my street. This allows them to have access to the resources they need and allow them to have a high level of fitness. Although they might be fit intraspecifically, it is clear that they are no match for their interspecific competition of the Red-bellied Woodpecker. Woodpeckers, both Downy and Red-Bellied, excavate their own nest in trees, using woodchips as their bedding, meaning they don’t have to collect many supplies. However, in order to have the energy to excavate these nests, they must have an adequate supply of food and protein. This can come in the form of insects, which there are plenty of in dying trees and surrounding areas.
After observing the Downy and Red-bellied Woodpeckers, I began my walk. As I walked, I noticed many American Robins, both singing in trees and foraging on lawns. They have been singing a lot recently, which indicates mating rituals. The male sings and puffs its feathers in order to attract a female mate. Hopefully, I will be able to see some American Robin nests in the near future, as it is around the time of the first eggs to be laid. American Robins use twigs, feathers, and mud to create their nests. There are a lot of available supplies of these in my neighborhood, so it shouldn't be hard for these birds to create good nests. However, there are not many good locations, as most of the trees line the streets. This could cause nests to fall into the streets.
As I continued my walk, I came across an area of my neighborhood that is very open and grassy. It is mowed by the community, so the grass is very short. There are a few trees along the border of this grassy area and the street. I heard a Northern Cardinal calling from a tree, and as I looked over he flew on to the grass and seemed to be foraging for food. I did some research, and as it turns out Northern Cardinals often have their first brood starting in March, so it is possible that this bird was foraging for his family (allaboutbirds.org). Northern Cardinals often nest in dense shrubs, which would explain that I was unable to find a nest. I also noticed three Mourning Doves perched on a power line. Since this is a group of three, and not two, I assumed that they are not breeding. Based on my research, when Mourning Doves aren’t breeding, they sleep in larger flocks (allaboutbirds.org). Although three isn’t really a large flock, this seems to be what they were doing.
I then saw two larger birds soaring above the trees. At first, I thought it was two American Crows, but upon a closer look, it turns out it was one American Crow and one Red-tailed Hawk. I thought it was very strange that an American Crow would follow a Red-tailed like this, so I looked up this action. American Crows are very territorial, and they know that Red-tailed Hawks are a threat (allaboutbirds.org). In order to lessen this threat, American Crows often try to get Red-tailed Hawks to leave their territory. This action of defense could suggest that the Ameican Crow has a nest nearby that it is trying to protect from the Hawk.
As I finished my walk, I head multiple Blue-jay calls but was unable to see them as it had gotten pretty dark and they seemed to be far away.
Overall, there were a lot of signs of breeding in my neighborhood! Hopefully, I will be able to identify some nests in the future and observe more activity.
Mini-activity: https://docs.google.com/document/d/16jvldkVi1u9lC9LzVXqwvlu4wTGS0tgCCyzV7B4BR8w/edit?usp=sharing
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