April 8th 2019: Field Observation 4
Date: 4/7/19
Time: 6 – 7:30
Location: Centennial Woods
Weather: 50 degrees, cloudy, light/no wind
Habitat: edges of urban and woods, marsh land, old growth softwood
While on my bird walk, I saw Black-capped Chickadee, American Robin, Red-winged Blackbird, and Northern Cardinal. Of the species that I identified only the Black-capped Chickadee and Northern Cardinal are non-migratory. Both species actively feed on seeds to survive. I think that this is the main reason that they can stay during winter. Both species also live in wooded and suburban areas that also allows them to adapt and find food during different weather. The way that these species can stay warm during the severe cold is by fluffing up their feathers. This allows the birds to keep warm air next to their body and cold air away from it.
Of my species I feel that Northern Cardinals are the only species that would be a potential facultative species. The reason I feel this is because during winter they may migrate short distances to find better resources in warmer climates, which would explain why I do not see as many during the winter. It is hard to tell where this species may migrate too as there is no information about Northern Cardinal migration. If this species did migrate, I would think that it would only migrate to areas such as southern Vermont where there may be less snow, warmer temperatures, and more food available. The main reason species migrate is because of a lack of resources. The Northern Cardinals will remain in this area for the rest of the year or until they felt the pressure of resources dwindling. With the warmer temperatures and the lack of snow, there are more available resources like seeds that will provide the species food. This species also eats bugs which have started to return to our area with the increase in temperature.
I believe that most of the migrant species that I saw were obligate migrants as they all feed on insects, bugs, and worms. They also eat some seeds and fruit, but this is only a supplement. Just like with the Northern Cardinal, the increase in temperature has allowed for insects, bugs, and worms to start to become present in the environment. With no snow these species are also able to forage more effectively. The increased temperature also allows the birds to survive as they do not have the ability to lower their body temperature and survive in a state of torpor like species such as the Black-capped Chickadee. The disadvantages of arriving this early is that the weather is very sporadic and fluctuates with temperature and the type of precipitation as seen late last week.
Mini Activity: total of about 1000 miles traveled if max migration took place.
- American Robin traveled short distances if any and the Red-winged Blackbird traveled about 800 miles from the furthest wintering area.
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