Field Journal 3
Location- Ethan Allen Homestead
Date- 3/6/24
Weather- Overcast, slight drizzle; 42 degrees Fahrenheit
Habitat- Silver maple ostrich fern floodplain forest; mixed hardwoods; wetland/grassland
Start time: 7:15 a
End Time: 8:30 a
Species list- American Robin, Northern Cardinal, Hairy Woodpecker, Black-capped Chickadee, Tufted Titmouse, Red-winged Blackbird, Mourning Dove, American Goldfinch
I decided to go to Ethan Allen Homestead for this field journal entry because I wanted to go birding in a floodplain forest habitat to see what species I would find. I stuck mostly to the path because it was quite muddy, but I was still able to hear some great vocalizations and see some cool behaviors. I counted a rough total of ~7 male and ~4 female Northern Cardinals, many of whom were interacting with each other; I assumed this was because the breeding season has started, as many of the males seemed to be in competition to get the females attention. I recorded a video of a male perched in a small shrub, repeatedly vocalizing without moving. I interpreted this to be a mating-behavior while saving energy, with the goal of attracting females. Once the female was close by, these vocalizations seemed to diminish or stop altogether, after which multiple males would fly at each other to try to ward them off the female. Another species that made repeated calls without moving was the Red-winged Blackbird, several of whom I identified in the fields and wetlands surrounding the homestead. These were also males, so I assumed they were also trying to attract potential mates while reducing energy expenditure.
Two birds I identified with starkly contrasting plumages were the Mourning Dove and Northern Cardinal. As I explained above, I saw several male cardinals in the trees and shrubs along the path. However, I saw one Mourning Dove fly up off the trail after I disturbed it from it's resting place. It was well-camouflaged because of it's plumage. An evolutionary advantage to the earth-toned coloration/patterns is that the dove can blend in with its surroundings well; seeing as its a largely stationary bird, to avoid predation and the subsequent energy loss caused by avoidance/fleeing, camouflaging with the ground would reduce these risks and costs that the dove faces. Conversely, the male northern cardinal has vibrant red coloration and plumage, likely an evolutionary advantage in competing for mates and in paternal success. The more vibrant the plumage, the more attractive the male is to females seeking the "best" mate, which confers success on the male via reproduction. Alternatively, I would assume that female cardinals have less colorful plumages to blend in with their nesting environment to avoid predation. Again, successfully avoiding predators without having to burst into flight to flee helps save energy and maximize metabolism, ultimately furthering the bird's success.
I couldn't track down a few Black-capped Chickadees within a close enough range to try the spishing sound, but I tried it around a small number of Dark-eyed Juncos. Several of them flew closer to my spot on the ground to investigate the noise before flying off. I assumed this sound mimics (to some degree of accuracy) a generic warning call, thus explaining why some birds would fly closer to investigate or fly off to avoid the identified risk. It is probably more successful in smaller flocks because the birds communicate with each other to warn one another of risks/potential predators, and the sound is meant to replicate this form of communication.
This was a fun bird walk and I got to hear some great bird vocalizations, and see some neat behavior- looking forward to the next one!
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