Archivos de diario de abril 2020

07 de abril de 2020

Field Journal #4: Migration

On Saturday, April 3rd, I went into Rock Creek Woods in NW DC from 2:00-3:00 pm. It was 65º and sunny with no wind. These woods are dense forest made mostly of deciduous trees with a few coniferous trees scattered throughout. The woods have an area of about 2.7 miles so for a city forest, it’s a large swath of land. In these woods, I observed an American Robin, Northern Cardinal, Downy Woodpecker, and Pileated Woodpecker. On Monday, April 6th, I sat in my backyard from 2:50- 3:30 pm. My neighbors have a feeder that many city birds come to, and there is a large deciduous tree next door as well as many shrubs in surrounding area. The weather was 70º, and very sunny with no clouds in the sky. There was a light breeze. I observed House Sparrows and a Mourning Dove.
The year round species I observed were House Sparrows, Downy Woodpecker, Pileated Woodpecker, and Northern Cardinal. These birds could be non-migratory for a variety of reason including that DC does not get very cold in the winter, and I believe this winter it did not even snow. So, it could be energetically efficient not to migrate because it stays warm here and there is not a lack of food or resources. I think the sparrows rely on bird feeders and tourists for food in the winter because I have only observed them in the cityscape and not in the forests. The cardinals and woodpecker rely on insects and seeds to survive, and given the warmth there could be insect living in the trees still. The cardinal most likely relies on seeds from rodent droppings or twigs to survive and probably looses wait to compensate for the lack of food.
The only migrant I observed was the Mourning Dove, and it is a facultative migrant in DC. According the Cornel Bird Lab, Mourning Doves in more northern states will migrate to southern states, Mexico, or even South America. However, given that DC is a central district, the doves are facultative. A reason they could be migrating is that their foods are not available during the cold, or that the migration is not very intense, and there is more resources in the south. Their migration depends on if the expending the energy to go south is worth the resources or if staying for the winter is more efficient. A common wintering ground for them is Texas, so I calculated the distance from DC to Dallas TX, and it is a 1,328.2 mile trip one way, and a 2,656.4 mile round trip migration.

Publicado el abril 7, 2020 05:10 TARDE por iadeslaw iadeslaw | 6 observaciones | 0 comentarios | Deja un comentario

13 de abril de 2020

Field Journal #6: Field Observations

On Saturday, April 11th, I went bird watching from 3:30-5:00 pm on the National Mall. I sat in a grove of cherry trees, and a long patch of tall deciduous trees. It was around 70º F, sunny with a light breeze. There were fair amounts of people out walking around, but not a ton. I observed European Starlings, American Robins, Common Grackles, Mallards, American Crows, Brown-headed Cowbirds, Rock Pigeons, Blue Jays, Ring-billed Gulls, House Sparrows, and White-Breasted Nuthatches.

Publicado el abril 13, 2020 03:38 TARDE por iadeslaw iadeslaw | 11 observaciones | 0 comentarios | Deja un comentario

20 de abril de 2020

Field Journal #7: Reproduction

On Monday, April 20th I observed birds around my neighborhood from 11:30 AM- 1:00 PM. I live in DC on Capitol Hill, and spring has completely come here with all the trees bearing leafs and many flowering trees already blooming. The weather was around 55º F, cloudy, and a bit windy. It has been cold and dreary for the past few days which has been unfortunate for birding. I live in a city so obviously this is not a lush forest, but there are many trees and bushes on each block. All the trees are deciduous and are either flowering trees (Pear, Cherry, Apple, and Dogwood), Black Walnut, Oak, and Maple Trees. I observed Northern Cardinals, European Starlings, House Sparrows, Gray Catbirds, Carolina Wrens, Mourning Doves, House Finches, and American Robins.
The House Sparrows were displaying a lot of behavior signals related to nesting. The most songs and calls were from sparrows, and these birds mostly create nests in under AC units in windows, in little burrows on the tops of houses, and other locations on buildings. I could tell that a nest was near because of increased singing and when I would look up, I could see a single male in a tree with his chest puffed, and then I would look at the adjacent building and there would be nests there along with a female. I know it's early but I could see and hear baby sparrows in the nests which could be why there were so many calls because the parents were actively protecting their young, and the males were guarding their mates. I observed individual sparrows carrying bits of dried grass, small swigs, and leaves in their beaks, which I assumed was for nest building.
When I walked outside my house, the air was full of calls and songs, but they were predominantly sparrows. They were in the tree next to me, the building besides my house, the buildings across from me, the air over my head and the trees. Building the sound map was a bit difficult because there were calls coming from all over. As I talked about earlier, the House Sparrows were nesting on the outside of buildings, but not other species were. This could be because the sparrows are small enough to make it work, but the Carolina Wren and House Finch were similarly sized. These species could be less accustomed to city living, so they nest in the trees because that is what the species has always done. The Carolina wrens were on the top of a tree together, so they could be building a nest in the high branches of a tree for protection because it is high up and a small nest is hard to spot.
(Link to the mini activity)

Publicado el abril 20, 2020 08:18 TARDE por iadeslaw iadeslaw | 8 observaciones | 0 comentarios | Deja un comentario

27 de abril de 2020

Field Journal #8

On Saturday, April 25th, I went into a small stretch of woods (about a half mile long) in North West DC that was made of deciduous tree that all had their leaves. There was a small pond in the middle that stretched the length of the woods and turned into a marsh area at the end. The weather was around 65º F, partly sunny, and no breeze. It had been raining for the past 4 days so the air was humid and the ground was still swollen with rain. There were puddles in the marsh area presumably from the rain. The trees were tall and dense making identifying species very difficult because it was hard to locate where specific calls were coming from. That being said, I observed House Sparrows, American Robins, Northern Cardinals, Carolina Wrens, Blue Jays, and a Mallard.

Publicado el abril 27, 2020 07:34 TARDE por iadeslaw iadeslaw | 6 observaciones | 0 comentarios | Deja un comentario