Another Slow Day

Captain Sam's:

Today was quite a slow day. I did enjoy that the wind was calmer today than it has been the past 2 days. We had a total of 23 birds captured today, with only 5 of the birds being recaptured. Our new first of the season are the Baltimore Oriole and Swainson's Thrush! Both of these birds were a treat to have on a slow day. Below, I am going to explain some intensified molt on a Red-eyed Vireo.

Most birds have a molt strategy were they replace old feathers with new ones before or after migration. Most adult passerines will replace their feathers right after they are done breeding or before they start their migration. There are exceptions to some individuals and species where they will suspend, meaning they will stop their molt, so they can migrate. Looking at the images below you can see I have highlighted a group of feathers called "greater coverts" in light blue. When comparing the two differences you can see the top photo has a similar growth, color, shape and wear to the feathers. When looking at the picture on the bottom, you can see how there is a difference in the wear and color on the feathers. Most people, at first glance, would think that this is a molt limit for a younger bird. When looking deeper into the feathers you can see how the wear on the feathers can help indicate a better age class for this bird. Generally a young bird born this year would have no wear to their feathers. An adult that has suspended their molt (new feather growth) would have worn and torn up feathers. Reading this article from Robert S. Mulvihill and Christopher C. Rimmer on "Timing and extent of the molts of adult Red-Eyed Vireos on their breeding and wintering grounds" it gives off a better explanation of what and why they do this kind of strategy.  

Photo: Hatch year Red-eyed Vireo

This photo you can see that all the feather wear is the same. The feathers look fresh and have a clean look to them. The molt limit would be in the alula (which my thumb is covering up "sorry") 

Photo: After hatch year Red-eyed Vireo

This photo you can see how the wear on the feathers is a little rough compared to the hatch year. Does not have a fresh clean look. The dark blue arrow and highlighted block, is where this individual started to replace some feathers but never completed the molt.

Hopefully this was very helpful and that you check out the link above to understand some molt strategies that birds do.

The radar is looking to be great tomorrow for migration, so keep your fingers crossed for some new first of the season!

-Kristin

Little Bear

After several low volume days due to a combination of unfavorable weather and minimal migration on Kiawah Island, we were graced with excellent conditions and met with a diversity of species—11 total. The captures from our first net run required five different band sizes. We also recaptured one of the Chuck-will's-widow banded on an earlier date at Little Bear. Each net run seemed to bring a new species for the day. A first of the season Baltimore Oriole was a particularly interesting catch. Little Bear usually only catches one a season. It is also notable that the Captain Sam’s crew caught one today as well. Josh tried his hardest to wish it into a Bullock’s Oriole, but birds simply don’t work that way. 

Migration is definitely picking up the pace. The Mississippi Flyway is certainly busy at the moment. Due to the path of hurricane Sally, however, the southeast Atlantic Coast has had a lull. That storm system acted like a brick wall preventing birds from coming eastward. Wind is a very important factor when you consider that the majority of the birds we band only weigh between 5 to 30 grams. When the wind blows from the west or north we usually catch more. The forecast is predicting a north wind tonight, so tomorrow may bring a cornucopia of new birds. 

-Vincent 

Species	Captain Sam's		Little Bear
	New	Recaps	New	Recaps
Chuck-will's-Widow	-	-	-	1
Traill's Flycatcher	2	-	-	-
White-eyed Vireo	1	1	-	-
Red-eyed Vireo	2	1	1	-
Carolina Chickadee	-	1	-	-
Carolina Wren	-	-	1	-
Gray Catbird	1	-	-	-
Veery	1	-	-	-
Swainson's Thrush	1	-	-	-
Baltimore Oriole	2	-	1	-
Ovenbird	-	1	2	-
Black-and-white Warbler	1	1	-	-
Common Yellowthroat	4	-	11	1
American Redstart	-	-	3	-
Yellow Warbler	1	-	3	-
Black-throated Blue Warbler	-	-	1	-
Prairie Warbler	1	-	-	-
Northern Cardinal	-	-	-	2
Painted Bunting	1	-	-	1

Today's Banding Stats	Captain Sam's	Little Bear	TOTAL
# Birds Banded	18	23	41
# of Recaptures	5	5	10
# of Species	14	11	19
Effort (net-hours)	150	105.6	255.6
Capture Rate (birds/100 net-hours)	15.3	26.5	19.9
# of Nets	30	22	-

2020 Fall Cumulative Banding Stats	Captain Sam's	Little Bear	TOTAL
# Birds Banded	885	483	1,368
# of Recaptures	265	94	359
# of Species	38	34	46
Effort (net-hours)	3,910	2050.8	5,960.8
Capture Rate (birds/100 net-hours)	29.4	28.1	29
# of Days	33	24	-

Banding Staff

Aaron Given (CS)
Sarah Mueller (CS)
Sarah Stewart (CS)
Vincent Weber (LB)
Dan Errichetti 
Kristin Attinger (CS)
Josh Lefever (LB)