4/28 Shelburne Pond

Our bird walk began around 6:20 pm today at Shelburne Pond. It had been raining earlier in the day, so the skies were overcast and cloudy, and there was a slight drizzle when we first arrived. Shelburne Pond offered a variety of different habitats to find birds, but we spent most of our time hiking through the mixed deciduous and coniferous forest. We started out, however, at the pond and the nearby marshes.
As soon as we stepped out of the car, our senses were assaulted by a chorus of Spring Peepers. The noise was so loud, in fact, that we almost couldn't hear a Red-winged Blackbird male singing from his perch in the marshes, defending his territory. He was relentless, however, and we heard him throughout our hike any time we came close to the area his territory was located in. A Turkey Vulture flew overhead as we scanned the pond for any signs of waterfowl. Although we didn't spot any, we did manage to locate a pair of beavers swimming through the water near the marshes, most likely foraging for food.
We headed up the trail leading into the woods. After several minutes of walking and not seeing a single bird, we realized we'd probably have to rely on songs and calls for identification, rather than visual cues. With that in mind, we followed a long, warbling song that we heard up ahead. We didn't recognize the song, but when we managed to locate the individual perched at the top of a tree, it's yellow coloration and black forehead identified it as an American Goldfinch. We continued walking down the path, and managed to see a large, black bird fly across the path, but didn't get a good enough look to identify it. Periodically, we heard American Robins calling from throughout the forest, and Canadian Geese flying overhead and congregating near the water's edge.
We moved deeper into the woods, not hearing or seeing anything but squirrels foraging in the under-story. As we kept walking, I caught a glimpse of a large, gray bird swoop through the trees and land on an exposed branch. I rushed ahead to get a better look before it flew off. From the distance, it had a distinctly owl shape, and was perching in a manner typical of a few of the owl species. Once I looked through the binoculars, I could easily make out the circular facial disk and brown barred feathers characteristic of a Barred Owl. We decided to sneak closer to try and get better pictures. The owl turned to look at us every once in a while, but overall seemed relatively unconcerned with our presence. We stood there, watching it, until it suddenly took off to another patch of trees. Seeing its general direction we followed. We hadn't been able to spot where it landed, but a few minutes later the owl flew off again. We headed in that general direction and tried to spot the owl once more. We couldn't see it, but after a few minutes we heard two of the Barred Owl begging calls somewhere ahead of us. We stayed for a while, trying to spot the owl one more time, but eventually we moved on. As we kept walking, we heard a long, flute-like song coming from the tree tops. After a few minutes of listening to the song, we identified the individual as a Hermit Thrush. It sounded like there might have been two that were singing to each other, but there was at least one male who sang non-stop for 10-15 minutes. As we walked down the end of the trail, we heard a Northern Cardinal briefly sing.
It was only as we exited the woods and walked back along the road leading to the parking lot that we realized the Barred Owl had followed us. Up on the treeline, we saw the gray-colored owl glide through the tree branches before perching once more. We played a Barred Owl call on our phone to see if it would call back. Although we didn't hear a response, after the audio clip was silent for a time, the Barred Owl again swooped through the air and flew closer to where we stood, presumably wanting to investigate the sound it had heard.
The primary behavior we observed during our walk related to mating behaviors was singing: we heard Red-winged Blackbird, American Goldfinch, and Hermit Thrush males singing long songs, probably to defend their territory and attract potential mates. Habitat requirements differ greatly among these species. Red-winged Blackbirds prefer open marshes, whereas Hermit Thrushes prefer areas with more tree-cover and low lying vegetation. The Red-winged Blackbird appeared to be defending a prime territory, as the marsh was fairly large and directly adjacent to a large pond and woodlot, providing plenty of resources and shelter. Because the territory appeared to be of such high-quality, it is reasonable to assume that the Red-winged Blackbird male we saw had a fairly high level of fitness.

Publicado el abril 29, 2018 03:42 MAÑANA por asmolens