FJ 5- Migration
On Tuesday, April 7, 2020, I went on an evening walk around my neighborhood with my mother and sister, from 5 pm to 7 pm. The weather was very nice; it was 60 degrees Fahrenheit and sunny. All the parks and most natural areas near me are closed, so I set out to observe some birds in my densely populated suburban town of Belmont, Massachusetts. Overall, the habitat consists of houses located very close together, with little open grass area available. There are trees that line the sidewalks and many bushes that are used as landscaping for these houses. There is also one small pond that has a bit more tree coverage than the rest of the neighborhood.
We started our walk outside of my house, where I could already hear calls of House Sparrows, but none were in sight. As we walked around the neighborhood, we came across many House Sparrows, both male and female, located in trees, gutters, and a lot in bushes. House Sparrows often do not travel more than a few kilometers in their entire lifetimes, making them a non-migratory resident species to my town. Walking along the sidewalk, I saw a Blue Jay fly by and land in a nearby tree and seemingly eat the budding flowers and fruit on the tree. Blue Jays are most likely year-long residents of this area of Massachusetts, although they sometimes are short-distance migrants. House Sparrows and Blue Jays survive the colder months by eating a lot during the day, mostly nuts, berries, and fruit, in order to be able to stay warm overnight, when they burn many of the calories they consumed in order to create heat. They also utilize techniques of plumping up their feathers and perching in protected shrubbery or tree cavities in order to conserve heat. I did some research and learned that Blue Jays also store food in the winter as a survival technique, which I thought was really interesting and did not know about (allaboutburds.com). They do this in order to save food for when they need it during the scarcer food months of winter.
As we continued walking through the neighborhood, we noticed many American Robins all standing, presumably foraging for food, in an open, grassy park area that was closed off to the public. Some American Robins migrate, while others are year-long residents to the same areas. In the winter, American Robins move in accordance to their wintering food source- fruit. Because of this, American Robins often move south and spread out from all the other American Robins in their breeding area, because there would not be enough winter food available for all of them in one place. As it is getting warmer, American Robins are able to feed on earthworms and insects again, allowing them to return to their breeding area, as there are enough resources available now. This makes American Robins facultative migrants, as they only migrate sometimes, as a response to the severity of winter and the scarcity of food.
We made it to the small pond with more tree coverage in the neighborhood. There, I spotted 4 male Red-winged Blackbirds in the trees around the pond. They all called multiple times, which made me look up and spot them in the trees. Two of them were engaged in a fight, perhaps over territory or food. Red-winged Blackbirds are sometimes full time residents of areas, but those who breed in northern North America can be migrants and travel very far south for the winter, all the way to parts of Mexico. When I was doing research, I noticed that in migratory Red-winged Blackbird populations, the males return before the females (allaboutbirds.com). This made me think that perhaps the Red-Winged Blackbirds that I saw do migrate, as they were all male. Since I saw so many Red-winged Blackbirds all so close together, it is possible that they have just returned in a flock from the south, like Mexico, and are now establishing their territorial areas (explaining the fighting I witnessed). Like American Robins, they migrate mostly for their food source.
Finally, on the way back to my home, we came across a singular Wild Turkey, which was strange given that often Wild Turkey’s stay in flocks. However, I assume that more Wild Turkey’s were around. Wild Turkeys are nonmigratory birds, but I wondered why I only ever see them in the warmer months. As it turns out, Wild Turkeys often spend more time in more densely forested areas in the winter, instead of the more open suburbs, because of food and coverage from the more extreme weather (allaboutbirds.com).
Unfortunately, I did not spot any obligate migrants. However, I believe that I have been hearing the song of the Eastern Phoebe recently, though I have yet to confirm my suspicion with a spotting. Eastern Phoebes migrate to the southern U.S. and Mexico and the winter and return North to areas including Massachusetts and Vermont. Eastern Phoebes are fly and insect catchers, although they can also eat small fruit and seeds. It is possible that returning north so early leads to the lack of sufficient resources of insects and bugs in the chillier states. Some positives of coming back north earlier would include the ability for migratory birds to establish their territories, forage, and prepare for the breeding season. Hopefully I will be able to see more migratory birds soon!
I have mapped the possible migratory patterns of Red-winged Blackbirds, American Robins, and Eastern Phoebes by using google maps (don’t think it is possible to add a picture, but here are the numbers added up).
Red-winged Blackbirds: Possible migration of up to 800 miles (allaboutbirds.com), I mapped from Belmont to North Carolina: 614 miles
American Robins: Short distance migration of about 60 miles
Eastern Phoebes: Long distance migration of up to 3,000 miles to Eastern Mexico
3,674 miles is the possible total of miles these migrants travelled in total to return to Belmont.
Source : allaboutbirds.com
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