Monday, December 5, 2016

2016 Fall Migration Summary

The 2016 fall migration banding season at the Kiawah Island Banding Station (KIBS) ended on Wednesday. We banded at two sites on Kiawah Island again this fall:  Captain Sam's and Little Bear.  This was the 8th consecutive year of fall migration banding at the Captain Sam's site with banding occurring daily during the last 5 years.  This was the 2nd 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 Sam's 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 7,308 birds and had 2,240 recaptures of 96 different species at both sites.

CAPTAIN SAM'S (west end)

Nets were opened for a total of 98 days from 15 August - 30 November.  We were shut down for a total of 10 days due to weather:  31 August for rain, 2-3 September for Tropical Storm Hermine, and 5-11 October for Hurricane Matthew.  This is the first year that a hurricane has affected our banding and it couldn't have come at a worse time - right at the peak of migration.  We had to remove all of our equipment from the banding site, and because of a mandatory evacuation, there were several good days of banding pre and post storm that we missed out on.      

We banded 3,869 new birds and had 1,187 recaptures of 84 different species.  The most commonly banded species were Common Yellowthroats (985), Yellow-rumped Warblers (739), and Gray Catbirds (447).  Those three species combined made up 56% of all the birds banded this season!

We also had a lot of recaptures from birds that were banded in previous seasons.  It will take a while to sort through all those records to determine how many unique returns we actually had as some of those were undoubtedly captured more than once during the fall.

Due to the addition of one net, our effort increased from 12,115.8 to 12,582.5 net-hours.
However, we banded 901 fewer birds and the capture rate decreased by 8.6 birds/100 net-hours compared to 2015.  This decrease can mostly be attributed to Hurricane Matthew which shut down the banding station for 7 days from 5-11 October which can be one of the busiest time of the fall season.  During that same time period from 2012-2015, the mean number of birds banded per year was 746 with an average capture rate of 91.1 birds/100 net-hours.  This can give us a reasonable sense of how many birds we may have "missed" during the hurricane.

The capture rate of recaptures is usually fairly constant only varying by a few tenths each season.  This year the capture rate increased by 0.1 recaptures/100 net-hours.

There were 7 days when over 100 birds were banded with 2 of those with over 200 birds banded. The best day of the season was on 25 September when we banded 255 birds and had 16 recaptures.  That was closely followed by 23 October when 205 birds were banded along with 24 recaptures.    

We banded 4 species that have never been banded at KIBS during the fall:  Red-shouldered Hawk, Loggerhead Shrike, Mourning Warbler and Red-winged Blackbird.

After a 2-year absence, we banded two Bell's Vireos this fall.  Prior to the 2016 fall banding season, we have banded one Bell's Vireo each fall from 2011-2013.  Some other rare and notable species that were banded this fall include:  Red-breasted Nuthatch (2), Brown Creeper (6), Winter Wren (1), Blackburnian Warbler (2), Rose-breasted Grosbeak (1), and Field Sparrow (1).  Some notable species absent this year include:  Blue Jay, Tree Swallow, American Goldfinch, Tennessee Warbler, and Summer Tanager.

Top 10 Species Banded at Captain Sam's
1.  Common Yellowthroat (985)
2.  Yellow-rumped Warbler (739)
3.  Gray Catbird (447)
4.  American Redstart (175)
5.  Red-eyed Vireo (1148)
6.  Ruby-crowned Kinglet (147)
7.  Prairie Warbler (124)
8.  Painted Bunting (102)
9.  Palm Warbler (84)
10.White-eyed Vireo (76)  


LITTLE BEAR (east end)

 Nets were opened for a total of 75 days from 22 August - 17 November.  We had 13 days cancelled due to weather:  31 August for rain, 2 September for Tropical Storm Hermine, 14 September for rain, 5-13 October for Hurricane Matthew, and 13 November for wind.  Little Bear missed out on several days of good banding pre and post hurricane.  It took a little longer to get Little Bear up and running after the storm because the several banding assistants were still scattered across the country trying to make their way back to Kiawah.    

We banded 3,439 new birds and had 1,053 recaptures of 74 different species.  The most commonly banded species were Yellow-rumped Warblers (659), Gray Catbirds (622) and Common Yellowthroats (621).  Those three species combined made up 55% of all the birds banded this season!

We logged 6,011.8 net-hours out at Little Bear this fall - a large increase from the 3,552.4 net-hours in 2015.  We started the season much earlier this fall (22 August) compared to last season (7 September) which gave us 18 more days of banding.  We also increased the number of nets we had in 2015 from 16 to 20.  

Little Bear had a very good capture rate at 74.7 birds/100 net-hours.  This was much higher than at Captain Sam's but slightly lower than in 2015 when we had a capture rate of 78.2 birds/100 net-hours.  Little Bear experienced a large increase in recaptures this year compared to last year (410 in 2015 and 1,053 in 2016) resulting in an increase of the capture rate from 11.5 to 17.5 recaptures/100 net-hours.    

There were 9 days when over 100 birds were banded with 1 of those days with over 200 birds banded.  The best day was on 23 October when we banded 207 birds and had 28 recaptures.

We banded 3 species never before banded at KIBS during the fall at Little Bear:  Yellow-crowned Night-Heron, Warbling Vireo, and Yellow-green Vireo.

The Yellow-green Vireo (a species that breeds in Mexico and Central America and winters in South America) was a huge surprise this season!  This species rarely makes it into the United States and would represent the first record for this species in the state of South Carolina.  We also banded 6th Bell's Vireo since 2011 and the first two Warbling Vireos for KIBS out at Little Bear this fall.  Some other rare and notable species banded include:  Wood Thrush, Bay-breasted Warbler, Black-throated Green Warbler, Field Sparrow, and Bobolink.


Top 10 Species Banded at Little Bear
1.  Yellow-rumped Warbler (659)
2.  Gray Catbird (622)
3.  Common Yellowthroat (621)
4.  Painted Bunting (157)
5.  Palm Warbler (143)
6.  Prairie Warbler (128)
7.  Red-eyed Vireo (125)
8.  American Redstart (95)
9.  White-eyed Vireo (86)
10.Yellow Warbler (84)

The 2016 KIBS Banding Crew
From left to right:  Nancy Raginski, Ryan Donnelly, Michael Gamble, Michael Rodgers, Aaron Given, Alison Nevins, Col Lauzau, Mattie VandenBoom.  Not pictured:  Blaine Carnes



SPECIES
CAPTAIN SAM’S
LITTLE BEAR
New
Recapture
New
Recapture
Common Ground-Dove
6
1
10
7
Mourning Dove
1
-
1
-
Yellow-billed Cuckoo
21
4
11
-
Chuck-will's-widow
1
-
-
-
Yellow-crowned Night Heron
-
-
1
-
Sharp-shinned Hawk
4
1
5
1
Cooper's Hawk
5
1
-
-
Red-shouldered Hawk
1
-
-
-
Eastern Screech-owl
3
1
-
-
Yellow-bellied Sapsucker
9
-
1
-
Downy Woodpecker
4
14
3
8
Northern Flicker
2
-
2
-
Eastern Wood-Pewee
2
-
1
-
Yellow-bellied Flycatcher
1
1
-
-
Acadian Flycatcher
7
-
-
-
Alder Flycatcher
3
-
1
-
Willow Flycatcher
4
1
-
-
"Traill's" Flycatcher
12
1
20
2
Least Flycatcher
1
-
2
-
Eastern Phoebe
21
2
23
-
Great Crested Flycatcher
7
2
-
-
Eastern Kingbird
1
-
1
-
Loggerhead Shrike
1
-
-
-
White-eyed Vireo
76
48
86
33
Bell's Vireo
2
3
1
-
Blue-headed Vireo
12
1
3
-
Warbling Vireo
-
-
2
-
Red-eyed Vireo
148
23
125
12
Yellow-green Vireo
-
-
1
1
Blue Jay
-
-
1
-
Carolina Chickadee
15
52
14
35
Tufted Titmouse
-
-
4
8
Red-breasted Nuthatch
2
-
-
-
Brown Creeper
6
-
-
-
House Wren
33
19
37
6
Winter Wren
1
-
-
-
Marsh Wren
4
-
1
-
Carolina Wren
11
58
17
68
Blue-gray Gnatcatcher
5
-
9
-
Golden-crowned Kinglet
20
1
9
-
Ruby-crowned Kinglet
147
30
69
10
Veery
15
1
8
-
Gray-cheeked Thrush
1
-
1
-
Swainson's Thrush
25
-
18
1
Hermit Thrush
45
29
17
2
American Robin
9
-
3
-
Gray Catbird
447
309
622
425
Brown Thrasher
13
12
12
12
Northern Mockingbird
12
15
20
15
House Finch
2
-
-
-
Ovenbird
17
6
19
2
Worm-eating Warbler
2
-
2
-
Northern Waterthrush
76
9
72
25
Blue-winged Warbler
1
-
-
-
Black-and-white Warbler
17
2
11
-
Prothonotary Warbler
16
-
-
-
Tennessee Warbler
-
-
3
-
Orange-crowned Warbler
18
10
16
4
Nashville Warbler
4
-
2
-
Mourning Warbler
1
-
-
-
Common Yellowthroat
985
43
621
84
Hooded Warbler
6
-
3
-
American Redstart
175
7
95
7
Cape May Warbler
3
-
14
-
Northern Parula
13
2
10
1
Magnolia Warbler
8
-
8
-
Bay-breasted Warbler
3
-
1
-
Blackburnian Warbler
2
-
-
-
Yellow Warbler
25
-
84
7
Chestnut-sided Warbler
2
2
-
-
Blackpoll Warbler
2
-
2
-
Black-throated Blue Warbler
74
-
37
-
Palm Warbler
84
-
143
-
Pine Warbler
1
-
-
-
Yellow-rumped Warbler (Myrtle)
739
209
659
59
Yellow-throated Warbler
1
-
1
-
Prairie Warbler
124
14
128
6
Black-throated Green Warbler
-
-
1
-
Wilson's Warbler
3
1
-
-
Yellow-breasted Chat
9
4
7
2
Eastern Towhee
10
14
11
10
Field Sparrow
1
-
1
-
Savannah Sparrow
-
-
1
-
Song Sparrow
29
6
28
6
Swamp Sparrow
57
44
58
20
White-throated Sparrow
15
1
1
-
White-crowned Sparrow
-
-
1
1
Summer Tanager
-
-
2
-
Scarlet Tanager
2
-
-
-
Northern Cardinal
48
128
42
86
Rose-breasted Grosbeak
1
-
-
-
Blue Grosbeak
1
-
3
-
Indigo Bunting 
17
-
27
-
Painted Bunting
102
52
157
86
Bobolink
-
-
1
-
Red-winged Blackbird
2
-
-
-
Baltimore Oriole
5
3
4
1








BANDING STATISTICS
CAPTAIN SAM’S
LITTLE BEAR
TOTAL
# of Birds Banded
3,869
3,439
7,308
# of Recaptures
1,187
1,053
2,240
# of Species
84
74
96
Effort (net-hours)
12,582.5
6,011.8
18,594.3
Capture Rate (birds/100 net-hours
40.2
74.7
51.3
# of Nets
26
20
46
# of Days Operated
98
75
-
Dates of Operation
8/15-11/30
8/22-11/17
-
Please note that these number are still preliminary and may change after the data is thoroughly proofed.

I would like to thank all those that made this season such a great success: the banding assistants (Mattie VandenBoom, Blaine Carnes, Michael Gamble, Ryan Donnelly, Alison Nevins, Michael Rodgers, Col Lauzau and Nancy Raginski for a couple weeks of volunteering);  the Town of Kiawah Island for proving funding for equipment and banding assistant stipends, and for allowing me to take on an extremely time consuming project;  the Kiawah Island Conservancy for providing funding for the housing of the banding assistants; Kiawah Partners and the Bear Island Holding Trust for allowing access to their property; and finally to all the volunteers that donated their time to either come out and help or just to observe.

Marsh sparrow banding will be starting up in a couple weeks.  I will try to do a better job at keeping up the blog throughout the marsh sparrow banding season.  We have an exciting new component to the marsh sparrow research this year.  We will be attaching small GPS tags to MacGillivray's Seaside Sparrows with the objective to figure out where birds wintering on Kiawah go during the breeding season.  We will also be able to learn more detailed information about the movements of Seaside Sparrow during the winter.

-Aaron