Arquivos de periódicos de abril 2020

08 de abril de 2020

Field Journal 5: Migration

Location: Green Mountain Audobon Center in Huntington, VT
Day: 4/7/20, 1:40-3:30pm
Partly cloudy, 53°F, subtle wind

• 1 Winter Wren
• 3 American Robins
• 12 Black-capped Chickadees
• 1 Blue Jay
• 1 Canada Goose (nesting!)
• 1 Red-winged Blackbird

I had never been to the Audobon Center before and yesterday’s beautiful weather seemed like a perfect opportunity to go. When I pulled into the parking lot, I was overwhelmed by the loud calls of Spring Peepers in Beaver Pond. Around the marsh I could hear the songs of Red-winged Blackbirds, one of Vermont’s famous facultative migrants. Red-winged Blackbirds are short-distance migrants who only travel about 800 miles south in the winter. Males arrive early in the spring and females join them later. The females then build their nests in marsh vegetation. The males will sing on high perches to attract females. The other day I saw a male desperately singing on top of a tree. I later saw a female sitting in a lower shrubby area by the water. I couldn’t tell whether she was impressed by his song.
Another facultative migrant species I saw was the American Robin. I started seeing these guys almost two months ago feeding on berries, but yesterday I saw a Robin tussling with a caterpillar—another sure sign of spring! These birds are year-round residents, but some of them are probably also arriving in VT from the southern United States. As the weather warms up in Vermont, American Robins are probably driven by the abundance of worms, caterpillars, and other invertebrates.

As usual, I saw a bunch of Black-capped Chickadees. Some were doing their mating calls in trees where I couldn’t see them, but most of them were hopping around the shrubs and feeding on berries. Staghorn Sumac seems to be a favorite, I just hope they develop the mental capacity to stay away from Common Buckthorn.

Unfortunately, I did not see any obligate migrants. I decided to do some research on the Scarlet Tanager, a bird that apparently dwells in the forest protected by the Audobon Society where I was doing my bird-walk. This bird that travels across the Gulf of Mexico to winter in South America. The individuals who migrate furthest arrive at their breeding grounds later than the ones who migrate further north on the continent. According to Google Earth, a Scarlet Tanager that travels in a straight line from northern Vermont to Ushuaia, Argentina, flies almost 7000 miles. The birds that go further south migrate north in synchronized bursts rather than all at once. They also migrate mostly at night. I wonder what their main orientation method is. They probably move at night to avoid predators because their bright, colorful feathers make them stick out. The American Bird Conservancy calls them “the guardians of the oaks” because they travel through the treetops of tall, deciduous trees (especially oaks).

Posted on 08 de abril de 2020, 06:36 PM by nlay4185 nlay4185 | 6 observações | 0 comentários | Deixar um comentário

15 de abril de 2020

Field Journal 6: Observations

April 15th, 2020
45 degrees Fahrenheit and partly cloudy
Wind direction: Northeast
Habitat: forest that passes near a river with many Eastern Cottonwoods, Boxelders, and different species of Maples. Shrubby dense habitat near the trail and marsh habitat closer to the floodplain areas.

1 Mourning Doves
1 Belted Kingfishers
4 Tufted Titmouses
1 Hairy Woodpeckers
2 Song Sparrows
12 Black-capped Chickadees

Posted on 15 de abril de 2020, 11:52 PM by nlay4185 nlay4185 | 6 observações | 0 comentários | Deixar um comentário

22 de abril de 2020

Field Journal 7: Reproductive Ecology and Evolution

April 20th, 2020
6:30am-8:15am
Derway Island Nature Trail
Sunny, 35°F

• 4 Mallards
• 5 Song Sparrows
• 10 Woodpeckers
• 1 Northern Cardinal
• 4 Canada Geese
• 1 Blue Jay
• 11 Black-capped Chickadees
• 1 Double-crested Cormorant
• 1 White-breasted Nuthatch
• 4 Tufted Titmice
• 1 American Goldfinch
• 3 American Robins

Some of the Robins I saw were sitting solo on a branch—usually of a tree with plenty of berries on it. When they were sitting alone, they made no sounds and just observed their surroundings vigilantly. It’s possible that these Robins were sitting on branches that were close to their nests. There were plenty of materials for nests covering the forest floor that they might have been looking around for. Later during my bird walk, I saw a Robin fly with amazing speed in a straight line across the Winooski River. Another Robin joined by its side. It’s possible that this was a pair flying off to their nest. They were flying too close to each other to not have some sort of relationship.

The Woodpeckers were everywhere. I saw a few, but was overwhelmed by the drumming that I heard in all directions. In contrast to the American Robin, Woodpeckers typically nest in cavities of snags. There were many snags throughout the area, but I didn’t see any evidence of nests. I did not want to be too nosy and scare anyone who was trying to set up a place for incubation. The woodpeckers I actually saw with my eyes were in close proximity to one another, but on separate trees. When one flew away, another one usually took its place, suggesting that they respect each other’s personal space but don’t mind sharing resources (at a distance). The frequent drumming I heard suggests that there were hundreds of Woodpeckers throughout the property trying to defend precious territory and/or attempting to find mates. In my opinion, the abundance of snags and diversity of the land suggests that there is a lot of prime territory. This might be why I saw Woodpeckers foraging relatively close to each other and not exhibiting aggressive behavior. It’s hard to say whether they had high fitness because of the plentiful resources. I wonder how they would do in a less ideal habitat.

The Mallards I saw were only in pairs. I didn’t get a great look at them because they flew away every time I got closer. They always landed together in the water after furiously quacking in the air. Their nest was probably on the ground on the other side of the river where there is less human activity. The other side of the river had a lot of marsh vegetation that would hide their nests well. It’s also probably a good place to easily pull pieces of shallow-root vegetation out of the ground without having he female having to leave her nest. I highly suggest this spot to anyone who wants to see a lot of birds and a diversity of great habitat!

Link to Mini Activity: https://docs.google.com/document/d/1qXdxtzLac7U49LNu6LZ-xLwENv_bm8dV0QoCDrUVzqY/edit

Posted on 22 de abril de 2020, 06:37 PM by nlay4185 nlay4185 | 12 observações | 0 comentários | Deixar um comentário

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