Field Journal 5: Migration
29 March 2023
Start: 8:30am
End: 10:00am
Location: Waterfront Bike Path & Oakledge Park, Burlington, VT
Weather: Sunny, 38 Degrees Fahrenheit.
Habitat: Lakeside. Urban park.
Species count:
- Common Goldeneye: 2
- House Sparrow: 1
- Red-winged Blackbird: 2
- Northern Cardinal: 1
- American Robin: 8
- Mourning Dove: 2
- Common Raven: 5
- Common Grackle: 1
- Canada Goose: 17
- Ring-billed Gull: 4
The bikepath proves again to be a great place to spot birds in the morning. It could just be that I’m out looking at a time where more species are active, but I’ve also found that edge habitats generally produce easier-to-spot birds. On my walk towards oakledge I was lucky to spot a few red-winged blackbirds and a sparrow. The blackbirds were making their “conk-ra-dee” call, a sure sign of warm weather soon to come. A few Canada geese cross the bridge beneath me, and I think about the soon-to-be flocks of couples with their goslings grazing on the lakeside. Spring is finally here.
Red-winged Blackbirds represent a species that only appears in Vermont to breed. While they may be spotted year-round just south and west of the state, the species is rarely found here in the winter. For species that experiences a short-range migration, my best guess for this behavior is that the blackbirds can’t compete with the species that overwinter in Vermont, whereas the may be more habitat in other parts of the country where they compete well in the cold months of the year. Another classic migrating species I spot on my walk to the park is the Canada Goose. The V-formation flocks make when migrating a stable if the fall, though not all individuals choose to migrate. I’ve seen Canada Goose nesting on the frozen Lake Champlain, and throughout the winter I would see individual to groups of three intermingling with mallards in the Winooski River. A large waterfowl like a Canada Goose would prove effective at surviving a Vermont winter. From a biological standpoint, the carrying capacity for large flocks of primarily grass-feeding geese decreases. A smaller number of geese may be supported, which is evident by the rement few who choose to stay. A benefit for this behavior could include having first choosing on territory to raise young. As the weather warms, forage will become more abundant. Older individuals may have a tried-and-true spot for raising young and go to lengths to claim it season-after-season.
Only a few of the species I observed, only four were not year-round residents. Canada Goose and Common Goldeneye may not overwinter in central Vermont, but their year-round range extends to the northern segments of Lake Champlain. Red-winged Blackbirds and Common Grackles are seasonal residents to Burlington, but may be found in southern Vermont. The only species I found that is not nearby year-round is the Ring-billed gull, who only stops in Vermont during migration. My estimate of the total distance these birds traveled to come here would 670 miles, and that is assuming the Ring-billed gulls found here migrated from the southern United States rather than Cape Cod.
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