CAPTAIN SAMS
After a nice streak of cool mornings the warm weather is back! It has continued to be relatively slow going at Captain Sams, but it ended up being slightly busier during the first half of the morning compared to the last few days. We banded 11 new birds and recaptured 6!
Although we just talked a little about cuckoos the other day, I want to take another look at a yellow-billed cuckoo we caught this morning and discuss another unique molt strategy we may occasionally see during fall migration. If the topic of molt interests you and you missed the last discussion regarding formative plumage and molt in songbirds, feel free to take a look back at August 20ths blog post titled "Eccentric Molt and Yellow-breasted Chats!" to get caught up to speed.
In most cases, when songbirds undergo a pre-formative molt it typically occurs and finishes on or near the breeding grounds before their fall migration begins. Oftentimes, this strategy is optimal as it allows those weak, juvenal flight feathers to be replaced with stronger, durable formative feathers before their long southbound migration begins. Some birds, like yellow-billed cuckoos, take a slightly different approach by performing what is referred to as a suspended molt. This strategy essentially breaks up the pre-formative molt into two parts; the first half will occur on the breeding grounds before migration begins and the second half will occur after their long journey once they've reached their wintering grounds. According to Pyle, "the pre-formative can begin on the breeding grounds with body feathers and sometimes includes replacement of at least p1 (the first primary flight feather) before suspension for migration".
In the case of our yellow-billed cuckoo, we observed just that! The first and second primary flight feather had been replaced, which was very cool to see! Once this bird reaches its wintering grounds it will likely completely finish molting its primary feathers and all will be new, formative feathers. Although we don't necessarily use this molt pattern to determine age in yellow-billed cuckoos and typically rely on shape and pattern of the tail feathers, this was very exciting to see.
Yellow-billed Cuckoo (hatch year, unknown sex)
Yellow-billed cuckoo undergoing pre-formative molt, but suspending the remaining juvenal primary flight feathers as discussed above; formative feathers in red and juvenal feathers in white
Thanks for hanging in there while we discuss some of these complex molt strategies! I hope you are enjoying reading them as much as I am writing them!
-Noah Nei
LITTLE BEAR
Today was a fun day out at Little Bear. We started out this morning normally but was interrupted by a little visitor, a small alligator stopped by for a visit since our water at the station is currently higher than normal. We didn't see it for the rest of the day and it might not show back up again. We ended our day with a total of 30 birds. Painted buntings still are currently our most popular captured birds at the station. We added 4 new species to the station for this season: green heron, common yellowthroat, traill's flycatcher and an early bird, gray catbird. It was nice to see these new species since this week seems like it will be warmer and will be slower for the station. There's always a chance of catching something amazing at least.
The green heron was a fun one to have in the hand since we don't typically catch many of them each year. Last year we ended with a total of 7, so maybe this year we might have more. In the image below you can see that this bird had a few different generations of feathers on the wing. Typically younger green herons will have a nice white edging on their greater coverts and on the inner primary and secondaries. This bird does not have any wedges left so this makes this bird an ASY (after second year bird). Check out our post from 2022 comparing a hatch year to an adult green heron. https://kiawahislandbanding.blogspot.com/2022/09/is-september-new-august.html
Here is the wonderful ASY Green Heron we captured today. Check out the wonderful generations in the wing.
 |
| Traill's Flycatcher (hatch year, unknown sex) |
-Kristin
Note: All banding, marking, and sampling is being conducted under a federally authorized Bird Banding Permit issued by the U.S. Geological Survey’s BBL
| Species | Captain Sams | Little Bear |
|---|
| New | Recaps | New | Recaps |
|---|
Green Heron | - | - | 1 | - |
Yellow-billed Cuckoo | 1 | - | - | - |
Downy Woodpecker | - | - | - | 1 |
Traill's Flycatcher | - | - | 1 | - |
Carolina Wren | - | - | 1 | 1 |
Gray Catbird | - | - | 1 | - |
Ovenbird | - | - | 1 | 1 |
Northern Waterthrush | - | - | - | 1 |
Black-and-white Warbler | - | 1 | - | - |
Swainson's Warbler | - | - | - | 1 |
Common Yellowthroat | 3 | - | 2 | - |
American Redstart | 1 | - | - | - |
Prairie Warbler | 1 | - | - | - |
Northern Cardinal | - | 2 | 2 | - |
Painted Bunting | 5 | 3 | 11 | 5 |
| Today's Banding Stats | Captain Sams | Little Bear | TOTAL |
|---|
| # Birds Banded | 11 | 20 | 31 |
| # of Recaptures | 6 | 10 | 16 |
| # of Species | 6 | 11 | 15 |
| Effort (net-hours) | 140.8 | 110 | 250.8 |
| Capture Rate (birds/100 net-hours) | 12.1 | 27.3 | 18.7 |
| # of Nets | 32 | 26 | 58 |
|
| 2024 Fall Cumulative Banding Stats | Captain Sams | Little Bear | TOTAL |
|---|
| # Birds Banded | 236 | 147 | 383 |
| # of Recaptures | 108 | 53 | 161 |
| # of Species | 27 | 23 | 34 |
| Effort (net-hours) | 1872.8 | 616.5 | 2489.3 |
| Capture Rate (birds/100 net-hours) | 18.4 | 31.4 | 21.85 |
| # of Days | 12 | 5 | - |
Banding Staff
Aaron Given (CS)Michael Gamble (CS)
Kristin Attinger (LB)
Natalie Miller (LB)
Lisa Viviano (CS)
Noah Nei (CS)
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