Migration has continued at a steady if not overwhelming pace for the past week, with the notable exception of yesterday (see totals below). Classic October migrants have been increasing such as Common yellowthroats and Painted buntings. In fact we had our best single day ever for Painted buntings on 11 Oct, with 11 birds banded. About a quarter were adult males and the rest were ‘greenies’, a mix of young birds of both sexes and adult females. Below is an adult male with a hatching-year male; young birds can be hard to sex but this individual was very bright green-yellow with a suggestion of the adult plumage in the bluish cast to the head and yellow-green back.
Each day the species composition changed a little bit, but in general the diversity was high. Some interesting captures included a Gray catbird originally banded in 2011 and a Great crested flycatcher banded in 2012; both by us so these are likely birds returning to winter at Cape Florida.
We also banded these two Tennessee warblers. They can be identified by a sharp pointed bill, fairly small size and plain underparts, if one is looking up in the canopy of a tall tree (a likely place to see them). They most resemble the Orange-crowned warbler, which is a later short-distance migrant that winters in south Florida. Orange-crowneds are completely yellowish below while Tennessees become whitish on the undertail coverts. Another warbler species that shares the same plain face pattern and also is migrating at this time is the Bay-breasted warbler, but a good look will show distinct wing bars and tail spots on a much larger bird, by warbler standards at least.
Below is a Prairie warbler mixed in with the two Tennessee warblers. The Prairie is a good example of a shorter-distance migrant with structural differences between them and the long-distance traveling Tennessee warblers. These birds are all a similar size but the Tennessees are somehow more ‘solid’ in the hand, likely due to greater musculature and fat loads. Tennessee warblers share the long wings and short tails with other warbler species whose final destination is South America, such as the Blackpoll warbler.
Radar indicated heavy flights down Florida for the last few nights, but with little to no rainfall overnight to bring them down the banding totals were modest. However, yesterday for some reason hundreds of birds landed at Cape Florida and 106 were banded. We perhaps could have had another 180 bird day if all the nets had been open all day, but one of the most important considerations when banding is to control the volume of captures so that individual birds do not have to wait too long to be processed and released. It can be very easy to get backed up on a busy day, especially if they all come in at once!
TOTALS 13 Oct 2015: 106 birds of 19 species
- Black-throated blue warbler: 27
- Common yellowthroat: 18
- American redstart: 12
- Northern parula: 10
- Gray catbird: 7
- Black and white warbler: 7
- Ovenbird: 7
- Northern waterthrush: 3
- White-eyed vireo: 2
- Swainson’s thrush: 2
- Swainson’s warbler: 2
- Painted bunting: 2
- Great crested flycatcher: 1
- Gray-cheeked thrush: 1
- Northern mockingbird: 1
- Brown thrasher: 1
- Tennessee warbler: 1
- Cape May warbler: 1
- Northern cardinal: 1
