FJ 5: Migration
For this assignment I went to the Ballard trail in Norwich, Vermont on April 7th, from 1:30-3:00pm. The weather was sunny and about 50 °F. I walked through my neighborhood to get there, so the habitat for the first and last 10 minutes of the walk was a paved road surrounded by houses, lawns, and trees. I saw a Blue Jay at a feeder and I think I heard a Brown-headed Cowbird but I’m not certain. While I was on the street I also heard House Sparrows, Black-capped Chickadees (both call and song), Northern Cardinals, and American Crows.
The Ballard trail follows a stream through the woods. Most of the area I was in consisted of tall coniferous trees, with some scattered deciduous trees. I only heard a few faint bird sounds at first, but I think that was because the noise from the stream made it difficult to hear. The first birds I saw were three small sparrow-sized birds that were on the ground and then flew up into the trees when I approached. I was able to find one with my binoculars and it looked like an Eastern Phoebe. Later I saw four more small birds hopping around in the branches of smaller coniferous trees. Two birds, a Black-Capped Chickadee and an Eastern Phoebe, were perched right next to each other and pecking at the branch they were standing on. I think their sides were touching, which I was surprised about since we learned that birds like to have personal space. Both species eat insects, so maybe they had found some food on the branch that they were both trying to get to. I didn’t see any birds for a while after that but started hearing more. On my way back, when I was closer to the stream again, I saw a White-breasted Nuthatch and an Eastern Phoebe in a tree between the path and the stream. They moved up the trunk and along the branches for a couple minutes, and then followed each other to a few more trees along the stream before flying apart.
One of the year-round resident species I heard was a Northern Cardinal. Northern Cardinals are able to survive the winter without migrating because much of their diet consists of seeds, which they are still able to find in the winter. One behavioral adaptation they have for overwintering is that they forage in flocks during the fall and winter, rather than sticking only with their mate as they do in the spring and summer. Brown-headed Cowbirds are facultative migrants. The one I saw was probably coming from south of Vermont, maybe around Connecticut, and is probably heading to northern Vermont or Canada. Part of their diet includes insects, which are coming out now that it is getting warmer, especially snails because females need a lot of calcium due to the large number of eggs they lay. Eastern Phoebes also migrate, but they go farther into the south of the US and even Mexico. They are one of the first migrants to return, which could be advantageous because they get to pick out niches and overhangs for nesting before other species arrive. A drawback of arriving early could be that their main food source, flying insects, are still less abundant due to the cold. The migration of a Brown-headed Cowbird and an Eastern Phoebe together could total around 1,800 miles.
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