Social Behavior & Phenology

Location: New Orleans
Date: 03/12/2019
Weather: 74 F. Partly Cloudy
Time: 1pm-3pm
Habitat: Swamp

Bird ID:
Belted Kingfisher: 3
Bald Eagle: 2
Great Blue Heron: 4
Great Egret: 3
Pileated Woodpecker: 1
Mallard: ~10
Black-bellied Whistling Duck: 2

When I went to Louisiana for spring break, I dedicated a few days to birding, one day on the Mississippi river, and the other in the swamps of Louisiana. I am going to write about the notes I took and observations I made from the swamp. I saw many birds, and could identify only the ones we saw in class and one a tour guide was able to tell me. We would stop to watch birds per my request, and witnessed 2 Great Blue Herons taking turns bringing up twigs and leaves to the top of a tree, which I assumed to be them building a nest. The two birds would make short squawking noises to each other as if they were greeting one another.

Furthermore, I saw a Bald Eagle (which was super exciting), and was able to hear another one! I didn't know they sounded like that and it took me by surprise when we saw the outline of one on a telephone pole calling. The calls were dispersed, and high pitched, which when I looked up the sounds found out it was a female telling potential mates that she is ready for copulation. This was extremely interesting to me, as the Bald Eagle was positioned out in the open on the tallest thing around, probably displaying herself and allowing all potential suiters to find her.

When watching the Mallards I noticed sexual dimorphism between the males and females, the male had a bright green head, while the female had a brown head. I believe this adaptation in the males' head color was evolved through sexual selection by the female. When compared to the Black-bellied Whistling Duck I observed, the males colors were extremely different, and believe these differences manifested due to speciation dependent on their natural habitats. I assumed these birds were just visiting the area for winter as I was. I decided to watch the Mallards for a while, and took note of their behaviors, which mainly included them bobbing their heads in and out of the water searching for food. The Mallards also stayed relatively close to one another, maybe because they are safer from an alligator in a pack than by themselves (higher chance its someone else rather than you). These behaviors make sense to the Mallards circadian rhythm because they sleep at night, and forage during the day. Considering it was one of the first warm days in Louisiana for s few weeks, the Mallards were probably soaking up the sun, and taking a dip in the cool water.

The pishing exercise I couldn't get to work in Louisiana, which I expect to be because I didn't really see many groups in flocks. When I returned home however, I attempted it on my way to school this morning. I walk through Centennial Woods every morning to get to campus, and always see Black-capped Chickadees, especially in the morning. This morning I would make "pish" sounds whenever I heard more than one individual calling. At first I began with low pishing, but nothing came nearby. I then began to use a high pitched pish, to which I could see some Black-capped Chickadees moving from the top of trees to a lower position to see what was going on. I also noted that the calls between individuals began to increase in frequency when i would "pshh". Over time I think I got pretty good at the pish and even elongated the shhh. During my final 10 minutes in the woods A large flock of Black-capped Chickadees flew over my head and landed nearby searching the ground. I believe that the pshh sound resembles that of a predator coming (sound of bush leaves moving), and made the birds more vocal to alert other individuals of a possible threat. However, I also saw some individuals getting closer, and flocks moving in around me, which could be explained by a type of defense mechanism, where the birds appear to be stronger in a group. The groups could also form because the sound resembles a potential food source, like seeds falling, or insects(?). This could explain a sort of group foraging behavior, that could benefit all in the flock.

Publicado el marzo 25, 2019 11:36 TARDE por rlooney