Archivos de Diario para marzo 2020

26 de marzo de 2020

Field Journal #4: Social Behavior & Phenology

Date: 3/25/2020
Time: 3:45 - 5:30 pm
Location: Calais, Vermont
Weather: Cloudy and warm; about 45 degrees
Habitat: Outcrop of Scots pine, with a low-lying marsh surrounding, within a birch forest.

For the most part, little to no observations could be made as to how different species were interacting with each other as the species observed were not near each other. However, interspecies interactions could be seen. For example, Ovenbirds were engaging in a back and forth of sorts from both the East and West (on the note of Ovenbirds, I know it is not their breeding season so I may have misidentified). Interestingly, no Black-capped Chickadees were heard or seen for the first half-hour of observing.

As prompted in the mini-activity, I began making a "psshh" noise, varying between 3 and 5 notes. Almost immediately, Black-capped Chickadees began to respond and within less than a minute, over 15 had flocked to the Scots pine outcrop. The Chickadees songs were varied, but short, only about 3 or 4 "dees", and due to their swift arrival as well, it seems as though they were communicating that there was little danger. With so many in such a small area, I expected to see some signs of aggression: heightened posture and raised feathers on the back of the neck, indicating that territory had been infringed upon, but for the most part, the Black-capped Chickadees remained calm, hopping from branch to branch and picking at the bark. I have heard of this technique but have never tried it. From what I have read about spishing, it is similar to the scold call of chickadees which is used to "mob" (gather) birds together. I was surprised at its effectiveness.

Shortly after the Black-capped Chickadees responded and arrived, a sharp increase in other species activity increased. American Robins arrived in nearby trees and were active in their calls. Although not close by, several American Crows were heard as well. Most interesting, a Ruffed Grouse was also heard (I did not know that they called but knew that they drummed). Based on the direction, it may have been the same Ruffed Grouse that had startled me when it vigorously flew it's perch as I approached my observation location. I was also able to hear the drum of a male Ruffed Grouse, which was not surprising considering the time of day. This drum is only heard during mating season as it is used to attract females. This makes it part of the species circannual cycle, although the tendency for males to perform this display for the most part in the early morning or early evening makes me wonder if it may be part of its circadian cycle as well.

The Ruffed Grouse has plumage that is important to camouflage. This species spends time on both the ground and in trees meaning that it is important that it can hide its self from a variety of predators. The Ruffed Grouse is a good example of cryptic coloration, as its plumage blends well into the forest floor as well as the branches of a tree. In contrast, the Black-capped Chickadee has a much lighter stomach than its back an example of countershading. Since this species is often in trees, it's predators mostly come from above and it's darker back makes them less noticeable to these predators.

Publicado el 26 de marzo de 2020 a las 01:58 AM por simonbradley simonbradley | 1 observación | 0 comentarios | Deja un comentario

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