UVM Ornithology Field Journal 7
Date - 4/25/21
Start time - 9am
End time - 10:30am
Location - clearing around a cabin in Weld, Maine.
Weather (temperature, wind speed/direction, precipitation) - 48 degrees Fahrenheit, 0 mph wind, 60% cloud cover, 15% precipitation.
Habitat(s) - clearing surrounded by mixed deciduous/hardwood forest that has been regrowing from having been cleared for sheep pasture up until the 1930s. Remote location ~1 mile trail hike from a road.
Some of the behaviors related to the breeding season that I observed were singing, increased aggression, and gathering nest materials. I watched one Red-breasted Nuthatch carry a large piece of chicken down it found on the ground into a nearby maple tree, where it stashed the down in the crux of two branches, subsequently abandoning it (the down blew away in the wind). This individual seemed to be performing behaviors related to nesting but hadn't yet found a suitable nest cavity. I assume other birds' feathers and animal hair may play an important part then in nuthatches' (as well as other birds') nests; I later saw the remains of a Ruffed Grouse that had been plucked nearby (presumably by an owl), and thought those feathers might be a good source of nesting material.
Many birds were also singing, including Eastern Phoebes. Eastern Phoebes nest in the eaves of our home each year, and this pair had been seen the prior day scoping out several potential nest sites on the building. Eastern Phoebes are not cavity nesters like nuthatches, which allows them more flexibility in finding suitable nesting habitats. Eastern Phoebes nest in somewhat more open habitats than some of the other species I observed, which show a preference for denser, more coniferous forests--e.g. the Yellow-rumped Warbler, Evening Grosbeak, and Purple Finch. There was a marked difference between the birds I saw at the feeder and heard singing (i.e., staking out territorial claims) in the clearing vs. when I walked out into the woods--chickadees, jays, nuthatches, juncos, phoebes, and sparrows (Chipping and Song) dominated in the clearing, and in the denser woods I also heard Hermit Thrush, a Winter Wren, a Blue-headed Vireo, and I flushed a Ruffed Grouse. This likely reflects different nesting habitat preferences for open vs. dense habitats and deciduous vs. coniferous.
Some of these birds were just arriving and staking out territory claims. Given how early they are, I would presume that the Winter Wren, Hermit Thrush, and Blue-headed Vireo that I already heard singing this early in the season were able to stake out high-quality territories before others got to them first. These birds may be more fit, e.g. if individuals that are in better physical condition are more likely to arrive on the breeding grounds early. Maybe they were able to fly faster during migration or leave earlier due to building up sufficient fat stores more quickly.
I found the mini-activity extremely hard! Surely there must be some standard way of notating bird songs by hand... Mine was a mess, but I'd like to learn because there have been times I heard a song in the field and didn't have my phone to record it but wanted to look it up later.
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