Field Journal 5

Date - 4/4/2021
Start time - 3:30 pm
End time - 5 pm
Location - Burlington Country Club
Weather - 56℉, 5 mph N wind, no precipitation
Habitat - suburban

On my birding excursion, I saw a couple of year-round residents that forego migration. These species of birds all seem capable of puffing their feathers out to keep more of their body heat from escaping. Some behavioral aspects that likely allow them to live in Burlington during the winter include their rationing of physical energy, so they don’t waste energy doing unnecessary things, and I’ve seen some species of year-round residents huddled together to keep warm in the colder temperatures.
Some birds are facultative migrants, like the Red-winged Blackbird and the American Robin, and travel short distances to another region typically to breed. These species don’t travel very far, but once they feel the weather starting to get better they migrate early in order for the males to set up a territory before the others arrive and try to claim an area for themselves. Specifically, the environment is getting warmer which signals to the facultative migrants that their breeding grounds are starting to get warmer. Since these species of birds don’t migrate long distances, they can judge the environment of where they will migrate to from their wintering location.
Obligate migrants arriving in early April have the advantage of being around when their prey is beginning to become more prevalent in their summer habitat and they can set up a territory before they start breeding. However, obligate migrants have the disadvantage of a cold spell they didn’t know about when migrating north that keeps their prey that live closer to Burlington in the winters from migrating, leading to a lack of resources for the obligate migrants. I only saw two migrant species on my birding excursion and they were both facultative migrants so they didn’t travel far but the rough estimate of the miles traveled by both species was 181 miles. This number would have been a lot greater if I had observed some obligate migrants on my birding trip, but unfortunately, I saw none.

Posted on April 5, 2021 03:17 AM by