Thursday, December 22, 2022

2022 Fall Migration Summary

 

The 2022 fall migration banding season at the Kiawah Island Banding Station (KIBS) concluded on Tuesday, 30 November. Banding occurred at two sites on Kiawah Island:  Captain Sam's and Little Bear.  This was the 14th consecutive year of fall migration banding at the Captain Sam's site with banding occurring daily during the last 11 years.  It was the 8th season for the Little Bear site which we initiated during the fall of 2015.  The two sites are located at each end of island about 8 miles apart (Captain Sams on the west end, Little Bear on the east end).  Both sites are situated in coastal scrub/shrub and high marsh habitats, however, the Little Bear site is in an earlier stage of succession.

Collectively, we banded 8,664 birds and had 2,229 recaptures of 99 different species.  Captain Sams had a substantial increase in the number of birds banded compared to last fall, while Little Bear experience a slight decrease. Combined, that increase translated into 11% more birds banded than last year. 

Along with the typical hot and humid weather, August was a wet one dumping 8.8” rain during the last two weeks. The heat and humidity continued through September with a handful of cold fronts that brought us good numbers of migrants and was capped off by Hurricane Ian on September 29 and 30.   Great migration conditions existed through much of October bringing substantial numbers of birds to the coast.  As usual migration slowed down in November but stayed steady throughout the month as scores of Yellow-rumped Warblers migrated to the area.  A rare late season tropical storm also passed through on November 10. 

CAPTAIN SAMS

Nets were opened for a total of 101 days from 15 August - 30 November.  There were 7 days when banding did not occur because of rain or wind (8/29, 8/30, 9/9, 9/29, 9/30, 11/10, 11/11). Unlike at Little Bear, Captain Sams can operate during windy conditions as there are some nets that are sheltered enough to open.  It is rare that wind alone will cause Captain Sams to completely shut down.

We banded 5,709 new birds of 86 different species.  The most commonly banded species were Gray Catbird (1,111), Yellow-rumped Warber (1,047) and Common Yellowthroat (1,026).  Those three species combined made up 56% of all the birds banded this season.  Gray Catbirds increased 6.9% from last year, and 24.8% over the 10-year average.  The 1,111 Gray Catbirds banded this year was the highest total over the past 14 years. After several years (2014-2020) of steady declines in Yellow-rumped Warbler numbers, they rebounded nicely last year but made a huge jump this year with a 52% increase over last year and a 40% increase on the 10-year average.  Common Yellowthroats fell to the number three spot for the first time ever this fall after exhibiting a 4.8 % decrease from last fall and a 9.0% decrease compared to the 10-year average.   

Several species exhibited record high numbers this season:  Black-billed Cuckoo (3), Chuck-wills-widow (5), Red-shouldered Hawk (1*), Downy Woodpecker (10), Great Crested Flycatcher (11), Eastern Kingbird (7), Tree Swallow (112), Gray Catbird (1,111), White-throated Sparrow (17*), Yellow-breasted Chat (26), Cape May Warbler (21), Bay-breasted Warbler (3*), Palm Warbler (270), Summer Tanager (6*), and Scarlet Tanager (6*). Alternatively, we had a couple species that had record low numbers:  Carolina Chickadee (2) and Carolina Wren (7*).  The * indicates species that tied the record high or low.    

The overall effort increased from 15,023.9 net-hours in 2021 to 15,292.6 net-hours this year despite banding on four fewer days.  2022 was a record-breaking year with regards to birds banded.  We banded 1,005 more birds this year compared to last year, and 1,143 birds more than the average for the previous 10 years.  The next highest fall season occurred in 2014 when 5,086 birds were banded.  The overall capture rate was 47.3 birds/100 net-hours. The capture rate increased by 6.5 birds/100 net-hours compared to last year but was 2.2 birds/100 net-hours lower than the 10-year average of 49.5 birds/100 net-hours.  Our capture rate has decreased every year starting in 2012 with exception to 2017 and 2019 when we experienced small increases from the previous year. The capture rate of recaptures is very consistent from year to year; therefore, all decreases in the total capture rate can be attributed to new birds.  The capture rate of recaptures this fall was 10.0 birds/100 net-hours. 

 



We had 1,529 recaptures which is higher compared to the 1,429 recaptures from last year.  Recaptures can be divided into 3 categories:  repeats (birds recaptured in the same season in which they were banded), returns (birds recaptured in a different season in which they were banded), and foreign recaptures (birds recaptured that were banded elsewhere). We had 1,307 repeats, 219 returns, and 3 foreign recaptures.  Foreign recaptures are exciting as they are birds that were not banded at Kiawah Island.  They are as follows:  

1.  Tree Swallow that was recaptured on 11/22/2022 and was originally banded as a nestling in Lido Beach, New York on 6/26/2015.  

2.  Yellow-rumped Warbler that we captured on 11/7/2022 and was banded at Long Point Bird Observatory in Ontario, Canada on 10/6/2022.  

3.  American Redstart that we captured on 10/18/2022 and was banded at Pelee Island Bird Observatory in Ontario, Canada on 9/22/2022.  

In addition, two birds that we banded this fall were recovered in Florida.  A Gray Catbird that was banded on 9/28/22 was hit by a car on 10/21/22 near Palm Coast, and a Palm Warbler that was banded on 10/18/22 was found dead on 11/1/22.     

There were 16 days this fall when over 100 birds were banded including 5 days with over 200 birds banded.  Last year we had no days over 200 birds and only 11 days with over 100 birds.  The best day of the season was on 9 October when we banded 246 birds and had 36 recaptures.  Of those 246 birds, 199 of them were Gray Catbirds!  The next two busiest days occurred 27 September and 5 October when 238 and 221 birds were banded, respectively. Favorable winds associated with several low-pressure systems (“cold fronts”) created good migration conditions during the second half of September and the first half of October. 

We captured one species that has never been banded at the Captain Sams site during the fall:  a Warbling Vireo.  Little Bear has banded 3 Warbling Vireos over the years, but they have evaded Captain Sams until 2022.    

Some other rare and notable species that were banded this fall include:  Black-billed Cuckoo (3; 2 previous), Red-shouldered Hawk (1, 2 previous), Yellow-belled Flycatcher (1, 8 previous), Alder Flycatcher (3, 8 previous), Eastern Bluebird (1, 3 previous), Chipping Sparrow (1, 8 previous), Lincoln’s Sparrow (1, 3 previous), Louisiana Waterthrush (1, 5 previous), Golden-winged Warbler (1, 1 previous), and Canada Warbler (1, 5 previous).

Species notably absent this year included:  American Robin (55 total, average 4.6/year), Baltimore Oriole (32 total, average 2.5/year), and Blue Grosbeak (28 total, average 2.2/year).

We hosted several groups this year including the SC Master Naturalist Program, AmeriCorps, Seabrook Island Birders Group, field trip during Kiawah’s Native Plant Week, and the Kiawah Island Photography Club.  ABC News 4 also featured a story on KIBS on 30 November.  Click here for the story. 

Top 10 Species Banded at Captain Sams

1.  Gray Catibrd (1,111)

2.  Yellow-rumped Warbler (1,047)

3.  Common Yellowthroat (1,026)

4.  American Redstart (366)

5.  Palm Warbler (270)

6. Northern Waterthrush (174)

7.  Ruby-crowned Kinglet (138)

8.  Painted Bunting (136)

9.  Red-eyed Vireo (135)

10.  Prairie Warbler (115)

LITTLE BEAR

Nets were opened for a total of 76 days from 22 August - 14 November.  Little Bear opened one day later and closed one day earlier than last year.  There were 9 days cancelled due to bad weather (rain and/or wind).  Because the habitat at Little Bear is more open than at Captain Sams, wind has a much bigger effect on the operation of the nets there.  As a result, two days were cancelled due to wind alone (9/23, 11/9) with another 7 due to rain (8/29, 8/30, 9/9, 9/29, 9/30, 11/10, 11/11).  An additional day (10/1) was cancelled the day following Hurricane Ian because we had not had enough time to put the nets back up the day before.    

We banded 2,955 new birds of 83 different species.  The most commonly banded species were Gray Catbird (746), Common Yellowthroat (446), and Palm Warbler (210).    Those three species combined made up 47% of all the birds banded this season.  Gray Catbird numbers exhibited only a 0.8% decrease compared to last fall but a 15% increase over the last 7 years.  Common Yellowthroat decreased by 31% compared to last year and 25% compared to the average of the last 7 years.  After a good year in 2021, Palm Warblers number were down 15% from last fall however remained 9% above the average of the last 7 years. 

Several species exhibited record high numbers this season:  Green Heron (4), Belted Kingfisher (6),  Merlin (1*), Acadian Flycatcher (1*), Golden-crowned Kinglet (10), Blue-gray Gnatcatcher (11), Swainson’s Thrush (30*), Saltmarsh Sparrow (2), Baltimore Oriole (8), Louisiana Waterthrush (1*), Northern Waterthrush (200), Black-and-White Warbler (26), Swainson’s Warbler (4), Tennessee Warbler (7*), Connecticut Warbler (2), Pine Warbler (3*), Wilson’s Warbler (1*), Scarlet Tanager (3), and Painted Bunting (208).  Species that had record low numbers included:  Carolina Chickadee (3), Brown Thrasher (2*), Gray-cheeked Thrush (1*), Wood Thrush (1*), Song Sparrow (15), Orange-crowned Warbler (5), and Prairie Warbler (37). The * indicates species that tied the record high or low.   

We logged 6,985.1 net-hours at Little Bear this fall – a large decrease from the 8,332.6 net-hours in 2021.  Many more banding days were cut short due to excessive heat and/or wind compared to last year.  In addition, we banded three less days than last fall. 

We banded 148 less birds this year compared to last year but 70 birds more than the 7-year average.  Little Bear’s capture rate increased 18% from 44.3 birds/100 net-hours in 2021 to 52.3 in 2022.  However, the capture rate decreased 15.4% compared to the 7-year average.


A substantial decrease in the number of recaptures has occurred each year from 2016-2019.  However, the number of recaptures has been increasing each year since.  This year we had 700 recaptures - 111 more than in 2021.  Of the 700 recaptures, 608 were repeats, 91 were returns, and 1 foreign recapture.  The foreign recapture was a Gray Catbirds that we captured on 9/24/2022 but was banded on Sullivan's Island, SC on 9/27/2021.        

There were 8 days when over 100 birds were banded – 3 more than last year.  The best day of the season was on 19 October when we banded 162 birds and had 22 recaptures.  The next two busiest days occurred 18 October and 5 October when 151 and 149 birds were banded, respectively.

We captured 4 species never banded at Little Bear during the fall:  Wilson’s Snipe, Great Egret (2), Snowy Egret, and Canada Warbler.  Wilson’s Snipe, Great Egret, and Snowy Egret have never been banded at either site before.

Some other rare and notable species banded included:  Black-billed Cuckoo (1; 2 previous), Green Heron (4; 4 previous), Belted Kingfisher (6; 1 previous), Merlin (1; 1 previous), Saltmarsh Sparrow (2; 2 previous), Lincoln’s Sparrow (2; 7 previous), Louisiana Waterthrush (1, 2 previous), Swainson’s Warbler (4, 4 previous), Connecticut Warbler (2, 1 previous), and Wilson’s Warbler (1, 2 previous).  Another interesting bird that was banded this fall was hybrid warbler.  It looked mostly like a Magnolia Warbler but there were a few features that were different – 1) it was bigger than a normal Magnolia Warbler, 2) the white in the tail was limited to the tips of outer tail feathers rather than a band on white across the middle of the tail like in a Magnolia Warbler, and 3) the underparts are completely washed out and pale yellow compared to the bright yellow of a Magnolia Warbler.  Tail feathers of this individual were collected, and we are hoping to be able to perform DNA analysis on them to determine its parentage.  Based on plumage characteristics, we think the most likely scenario is a Magnolia Warbler/Yellow-rumped Warbler cross.  Photos of this bird can be seen here.    

Species notably absent include Eastern Screech-Owl (15 total; average 2.1/year), Marsh Wren (13 total; average 1.9/year), and Savannah Sparrow (11 total; average 1.6/year). 

Top 10 Species Banded at Little Bear

1.  Gray Catbird (746)

2.  Common Yellowthroat (446)

3.  Palm Warbler (210)

4.  Painted Bunting (207)

5. Northern Waterthrush (200)

5.  Yellow-rumped Warbler (154)

7.  American Redstart (130)

8.  Red-eyed Vireo (58)

9.  Black-throated Blue Warbler (56)

10. Ruby-crowned Kinglet (56)

ACKNOWLEDGEMENTS

Without the cooperation of many people and entities, this work would not be possible.  The success of this project relies on their commitment, and I am in a debt of gratitude to everyone involved. 

First, I'd like to thank my awesome team of banding assistants (Kristin Attinger, Nate Watkins, Brendan Wang, Maia Nguyen, Aidan Place, Katie Serba).  Their hard work over the course of this long season was outstanding.  It was a great season, and I would like to wish them all the very best of luck in the future. 


From left to right: Katie Serba, Aidan Place, Aaron Given, Maia Nguyen, Kristin Attinger, Nate Watkins, Brendan Wang


Next, I'd like to acknowledge the Town of Kiawah Island for providing funding for equipment and banding assistant stipends, the Kiawah Island Conservancy for providing funding for the housing of the banding assistants, and the Kiawah Partners and the Bear Island Holding Trust for allowing access to their property for banding.

David McLean, Jenna Charydczak, Aidan Given, Michael Gamble, Nancy Raginski, Adam Wolf, Chris Snook, Cathy Miller, Wes Floyd all donated a considerable amount of their time (more than 10 hours) to help.  We also had several others that came out for just the day. I’d like to thank all the volunteers that made it out this year. Because of their help, we can operate a more efficient banding station.

SPECIES

CAPTAIN SAMS

LITTLE BEAR

New

Recapture

New

 Recapture

Common Ground Dove

3

1

-

-

Mourning Dove

4

1

1

-

Yellow-billed Cuckoo

18

-

14

2

Black-billed Cuckoo

3

1

1

-

Wilson's Snipe

-

-

1

-

Great Egret

-

-

2

-

Snowy Egret

-

-

1

-

Green Heron

-

-

4

-

Chuck-will's-widow

5

-

1

-

Sharp-shinned Hawk

4

3

1

1

Cooper's Hawk

1

-

1

-

Red-shouldered Hawk

1

-

-

-

Eastern Screech-Owl

1

-

-

-

Belted Kingfisher

-

-

6

 

Yellow-bellied Sapsucker

7

-

4

-

Downy Woodpecker

10

28

7

3

Northern Flicker

1

-

1

-

Merlin

-

-

1

-

Eastern Wood-Pewee

6

-

2

-

Yellow-bellied Flycatcher

1

-

-

-

Acadian Flycatcher

1

-

1

-

Alder Flycatcher

3

1

-

-

Willow Flycatcher

3

-

-

-

"Traill's" Flycatcher

13

-

11

-

Least Flycatcher

1

-

-

-

Eastern Phoebe

52

2

36

1

Great Crested Flycatcher

11

6

-

-

Eastern Kingbird

7

-

2

-

White-eyed Vireo

53

60

43

14

Blue-headed vireo

6

2

2

-

Warbling Vireo

1

-

-

-

Red-eyed Vireo

135

12

58

-

Carolina Chickadee

2

12

3

3

Tufted Titmouse

-

-

1

1

Tree Swallow

112

1

-

-

Golden-crowned Kinglet

12

-

10

-

Ruby-crowned Kinget

138

63

56

2

Blue-gray Gnatcatcher

17

5

11

-

House Wren

67

29

52

6

Marsh Wren

1

-

-

-

Carolina Wren

7

33

18

48

Gray Catbird

1,111

581

746

240

Brown Thrasher

6

9

2

1

Northern Mockingbird

16

15

9

-

Eastern Bluebird

1

-

-

-

Veery

16

-

7

-

Gray-cheeked Thrush

6

-

1

-

Swainson's Thrush

70

2

30

2

Hermit Thrush

29

11

7

1

Wood Thrush

5

-

1

-

House Finch

16

-

1

-

Chipping Sparrow

1

-

2

-

Clay-colored Sparrow

1

-

-

-

Field Sparrow

4

-

-

-

White-crowned Sparrow

1

-

1

-

White-throated Sparrow

17

6

2

1

Saltmarsh Sparrow

4

-

2

-

Savannah Sparrow

2

1

-

-

Song Sparrow

53

19

15

8

Lincoln's Sparrow

1

-

1

-

Swamp Sparrow

38

15

33

7

Eastern Towhee

5

4

9

7

Yellow-breasted Chat

26

12

11

5

Baltimore Oriole

-

-

8

-

Ovenbird

45

32

26

2

Worm-eating Warbler

2

-

2

-

Louisiana Waterthrush

1

-

1

-

Northern Waterthrush

174

48

200

66

Golden-winged Warbler

1

-

-

-

Black-and-white Warbler

40

5

26

2

Prothonotary Warbler

9

-

6

-

Swainson's Warbler

-

-

4

9

Tennessee Warbler

4

-

7

-

Orange-crowned Warbler

16

6

5

3

Nashville Warbler

3

-

1

-

Connecticut Warbler

-

-

2

-

Common Yellowthroat

1,026

101

446

16

Hooded Warbler

4

-

2

-

American Redstart

366

64

130

11

Cape May Warbler

21

2

24

-

Northern Parula

40

-

20

-

Magnolia Warbler

12

1

7

-

Bay-breasted Warbler

3

-

3

-

Yellow Warbler

28

2

55

3

Chestnut-sided Warbler

2

-

2

-

Blackpoll Warbler

6

-

7

-

Black-throated Blue Warbler

108

4

56

-

Palm Warbler

270

-

210

1

Pine Warbler

1

-

3

-

Yellow-rumped Warbler (Myrtle)

1,047

180

154

11

Yellow-throated Warbler

2

2

1

-

Prairie Warbler

115

19

37

3

Canada Warbler

1

-

1

-

Wilson's Warbler

-

-

1

-

 "Hybrid" Warbler

-

 

1

 

Summer Tanager

6

-

-

-

Scarlet Tanager

6

-

3

-

Northern Cardinal

22

59

33

55

Blue Grosbeak

-

-

2

-

Indigo Bunting

56

5

29

1

Painted Bunting

136

64

207

165


BANDING STATISTICS

CAPTAIN SAMS

LITTLE BEAR

TOTAL

# of Birds Banded

5,709

2,955

8,664

# of Recaptures

1,529

700

2,229

# of Species

86

83

99

Effort (net-hours)

15,292.6

6,985.1

22,277.7

Capture Rate (birds/100 net-hours)

47.3

52.3

48.9

# of Nets

30

23

-

# of Days Operated

101

75

-

Dates of Operation

8/15-11/30

8/22-11/14

-

Please note that these numbers are preliminary and may change after the data has been thoroughly proofed.

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