FJ4: Social Behavior and Phenology

On Sunday, March 22nd, around 12pm, I arrived at the Dead Creek Wildlife Management Area in Addison, VT. I was with my dad, and we drove around to multiple locations, seeing many birds while we were driving, including several Red-tailed Hawks, Canadian Geese, and Mallards. It was only around 28°F, and there was a strong wind that showed up periodically. Dead Creek is a wetlands area in the Champlain Valley surrounded by agricultural fields, and is a common stop for many migratory birds during springtime. We were a few weeks early for there to be as many birds as my dad has seen there in the past, but there were still several large flocks. Other birds we saw include: Common Grackle, American Wigeon, Blue Jay, Black-capped Chickadee, House Sparrow, (Herring?) Gull, Turkey Vulture, and American Robin.

One bird that was seen the most often on our adventure was the Common Grackle. They were seen in multiple large flocks, and although it was hard to get close to them before they took off, they were also very vocal. I was able to capture two great sound recordings of them, when they were hiding in the shrubbery (linked to my observation post). The most common sound made by them was a short, grating song that sounded kind of like a rusty gate, when they were communicating with each other. I noticed that when some of the birds made their rusty-gate song, they puffed out their feathers, perhaps as a mating show for the females. However, whenever they took off, their alarm call was high, squeaky, and grating, and the entire flock would get up and relocate.

One bird with very different plumage from the Common Grackle is the Blue Jay. While the Grackle looks dull brown from a distance (even though I could see the golden eye and iridescent blue head and oily-looking body through binoculars), the Jay is easy to spot without binoculars because of its bright blue and white feathers. While the Grackle was able to blend into the trees really well (I spent quite some time listening to them, but was unable to see them when they hid in the brush), the Blue Jay can't really hide among the brown dullness of early spring. The evolutionary advantage of blending in is that you can hide from predators, while the advantage of being colorful is that it's easier to prove to potential mates that you are strong and healthy, without so much of an energetic display.

One individual bird I focused on was a Red-tailed Hawk that spent some time circling over the field next to the path I was walking on. It was obviously hunting something, and was circling until it had its chance. After awhile, it dove down towards the field, but pulled up before reaching the ground, apparently because its prey burrowed back into the ground. Eventually, the hawk circled back up into the air and flew off, in search of another meal. This fits into its circannual rhythm because it is probably getting ready to mate, and raise its young. To do so, it has to be strong enough to provide food, which means it needs to eat enough food for itself, as well.

When we came across the small group of Black-capped Chickadees, they were much less skittish than the other birds we encountered. We were able to do the "pish" calls, and apparently we did it right, because a few more chickadees appeared, and the ones that were there came a little closer to investigate. It almost seemed like the pishing alarmed them, and they were gathering together for safety in numbers. I also wondered if the spishing sounds replicated insect noises, and they were looking for prey?

Posted on March 24, 2020 03:40 PM by mnwaterman