CAPTAIN SAM'S
The cold front brought in some cooler temperatures but unfortunately, not many birds. The front also brought with it - wind. We experienced gust up to 15 mph which is not conducive to mist netting. The wind blows the nets around making it easier for the birds to see and avoid them.
The wind wasn't all bad though as it helped us catch some more Tree Swallows. Certain weather conditions have to occur to catch Tree Swallows in mist nets: 1) cooler temperatures, 2) wind and 3) overcast skies. You don't necessarily need all three to occur to be successful though. Tree Swallows are mainly insectivores catching flying insects on the wing but when its cold, windy, and/or overcast those flying insects are not flying so much and the swallows need to find an alternative food source. Wax myrtles are a very common shrub that grows in the dunes and shrublands of Kiawah Island. Female plants produce small grayish-green fruits that are coated in a waxy substance. The Tree Swallow's ability to digest the waxy coating enables them to winter further north than any other species of swallow.
When Tree Swallows decide that it is time to feast on wax myrtle berries, they gather in huge groups sometimes numbering in the thousands. We estimated today's group was about 800. They seek out a single wax myrtle shrub or a clump of wax myrtles that is somewhat isolated and in the open. They begin to hover over the shrub and then start circling like a tornado, and then all at once ascend into the wax myrtles to feed on the berries. They may do this over and over again throughout the day until they've stripped the shrub of its fruit. To see a video of the "Swallow-nado" check out this post from 2014.
A couple weeks ago when the Tree Swallows arrived and started feeding on wax myrtles, we set up a net adjacent to an isolated wax myrtle that they were feeding on and caught 5 of them. The swallows have been back most days but haven't returned to the shrub with the net is until today. The wind prevented us from catching more but during one of their feeding frenzies, we were able to catch 10 Tree Swallows. In today's small sample from the flock of 800 strong, we had 4 adult females, 3 juvenile females, 2 juvenile males, and one adult that we weren't sure on.
Ageing Tree Swallows in the fall is difficult. Both juveniles and adults undergo a complete molt therefore plumage characteristics are not helpful and we must "skull" the bird to determine its age. To learn more about skulling, check out another post from 2014.
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| Tree Swallow (hatch-year female) Notice how brown she is overall. |
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| Tree Swallow (either adult female or hatch-year male) |
Tomorrow's weather isn't looking great as the winds are supposed to increase overnight. It appears that I will be greeted with 20 mph winds and a wind chill in the upper 30's in the morning.
-Aaron
| Species | Captain Sam's | Little Bear | ||
|---|---|---|---|---|
| New | Recaps | New | Recaps | |
Ruby-crowned Kinglet | 1 | 1 | - | - |
Gray Catbird | - | 3 | - | - |
Tree Swallow | 10 | - | - | - |
Song Sparrow | 1 | - | - | - |
White-throated Sparrow | - | 1 | - | - |
Yellow-rumped Warbler (Myrtle) | 17 | 3 | - | - |
| Today's Banding Stats | Captain Sam's | Little Bear | TOTAL |
|---|---|---|---|
| # Birds Banded | 29 | - | - |
| # of Recaptures | 8 | - | - |
| # of Species | 6 | - | - |
| Effort (net-hours) | 184.2 | - | - |
| Capture Rate (birds/100 net-hours) | 20.1 | - | - |
| # of Nets | 30 | - | - |
| 2021 Fall Cumulative Banding Stats | Captain Sam's | Little Bear | TOTAL |
|---|---|---|---|
| # Birds Banded | 4473 | 3103 | 7576 |
| # of Recaptures | 1149 | 589 | 1738 |
| # of Species | 91 | 79 | 104 |
| Effort (net-hours) | 13085.85 | 8332.6 | 21418.45 |
| Capture Rate (birds/100 net-hours) | 43.0 | 44.3 | 43.5 |
| # of Days | 91 | 78 | - |
Banding Staff
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