Spring Migration Bird Banding 2015
Mass Audubon’s
Wellfleet Bay Wildlife Sanctuary
Prepared by James Junda
July 2015
About Wellfleet Banding Station
Wellfleet Bay Wildlife Sanctuary (41.883 N, 69.996 W) is located in South Wellfleet, MA and is owned
and managed by Mass Audubon. The banding station is managed by James Junda with the cooperation
and assistance of sanctuary staff. Two experienced and licensed banders operate the station daily from
April 15 – May 31 and September 1 – November 15. Volunteer assistance is used when available and
appropriate.
It is a valuable addition to a growing collection of banding stations on Cape Cod, being the only station
located on the Outer Cape. Two constant effort-banding stations are already in operation on or near Cape
Cod: Wing Island Banding Station in Brewster (20 km to the WSW) and Manomet Center for
Conservation Science (50 km to the E).
Operations are based upon the protocols of other constant effort banding stations in the United States and
Canada with an emphasis on standardized research protocols. In addition to collecting and analyzing
scientific data to assist in management decisions, Wellfleet Banding Station serves to increase public
interest on the sanctuary, Cape Cod and around the world.
History of Banding at Wellfleet Bay
The bird banding pedigree of this property runs deep. The first bird banding station on the property was
established in 1929 when well-known ornithologist Dr. Oliver Austin Jr. founded the Austin
Ornithological Research Station with his father, Dr. Oliver Austin Sr. The Austins initially caught and
banded waterfowl, shorebirds, terns, sparrows and blackbirds using a variety of traps, and likely began
mist netting songbirds in the 1940s and 50s, when Oliver Jr. introduced the first Japanese mist nest to the
United States. Mass Audubon took over the property in 1958 and continued the ornithological research
begun by the Austins. Some amount of bird banding has occurred on the property in 60 out of the last 85
years. Erma “Jonnie” Fisk banded at the sanctuary regularly between 1972 and 1989, mainly for the
purpose of public education. 1989 marked the last year of regular banding on the property until 2014.
The abundance of certain birds in the banding data from the Austin years reflects both the methods used
by the Austins (duck, sparrow, and tern trapping), as well as the vastly different landscape of Cape Cod
during the first half of the 20th century. Open country species like Vesper Sparrow and Grasshopper
Sparrow, all but extirpated from the now heavily wooded Outer Cape, were common on the treeless postagricultural landscape of the Austin era. For example, they reported 183 Vesper and 51 Grasshopper
Sparrows banded in 1931 alone (Austin 1932). Incomplete banding data were obtained from the Bird
Banding Lab from the Austin years, but based on Austin’s publications it is clear that much of it is
missing. Digitization of the full Austin banding records housed here at Wellfleet Bay sanctuary would be
a massive undertaking, but would allow for more complete comparison with contemporary data.
Spring Migration Banding
Spring migration banding is a standardized study undertaken annually. It provides the basis for long-term
trend analysis of migrating birds using the sanctuary. It is designed to be comparable with the
methodology of other spring migration banding stations. The protocol involves regular standardized
banding operations with mist-netting effort remaining constant daily, seasonally and annually. The spring
migration season extends from April 15 - May 31 with nets open every day at dawn and remaining open
for 5 hours (weather permitting). This period encompasses the majority of spring passerine migration,
giving a thorough view of the majority of the process while allowing us to operate the station without
conflicting with the popular summer events and classes at the sanctuary.
Outreach and Public Programs
One of our primary goals is to increase knowledge and expose the public to the avian life on the
sanctuary. To this end, we attempted to schedule banding demonstrations twice a week in the spring and
made ourselves available to any special visitors to the sanctuary. While the paid banding demonstrations
were not as well attended as we would have liked, we are hopeful that continued exposure and better
weather in the fall will improve attendance. We recorded a total of 20 organized visits from different
groups in Spring 2015. There were six school visits, when students from kindergarten to college-age came
to the station, learned about operations and helped release birds. We also had four donor groups, when we
allowed intensive hands-on interaction and encouraged them to understand the value of the research and
the importance of the sanctuary to the birds. Three camp groups came to visit the station and spent an
hour or two seeing birds in hand, adding to the other interesting activities the kids experience in these
programs. Volunteer day was a big hit; we were very happy to provide these important people a chance to
experience birds in a unique way, and even see a Sharp-shinned Hawk in the hand! Finally, Wings Over
Wellfleet was on a windy day, and we did not catch as many birds as we would have hoped. Let us hope
for better weather in upcoming seasons so we can feature more birds during this well-attended event. All
told, we had 20 visits from various groups in the 47 days of the season, representing a strong outreach
effort in Spring 2015.
2015 Season Coverage
In 2015, the banding season started on April 15 and ended on May 31. An additional short banding demo
was performed on June 2, with three nets open for 1.66 hours each. We operated up to a maximum of 16
nets on 44 days for a total of 2698.64 hours. Coverage of Wellfleet Banding Station in 2014 was good,
reflecting the pleasant spring weather, and we banded on 44 of 47 days. We encountered several bouts of
high wind and, in general, wind was a large factor in net effort, but as spring progressed and leaves began
to emerge, the effect of the wind was diminished.
The standard setup included 16 nets along two loops, but the mesh size, age and make varied among nets
used. Nets 17 and 61 (a 6m net) were added on April 30th and used through the rest of the season. Wind
direction and speed had a huge impact of net effort. On most days, some nets could not be open or had to
be closed due to wind. Small variations in direction could change which nets were affected, but in general
nets along the Bayview loop were more exposed and closed more often than those along Silver Spring.
Wind is a near constant presence on the Outer Cape and should affect operations in a similar fashion in
future seasons.
Banding
During Spring 2015 operations, we had 1073 captures of 65 species (Appendix A): 596 newly banded
birds, 439 local recaptures and 38 unbanded. Below, we look at the number of birds banded by date (Fig
1), next we standardize for effort by looking at the number of birds banded/100 net hours (Fig 2).
Figure 1- Number of birds banded by date at Wellfleet Bay Wildlife Sanctuary during Spring 2015 operations.
Blue line is daily captures, while the red line is a 3-day running average. Captures rates peaked around May 6th, then
slowly declined until the end of the season.
The second day of banding (16-Apr) was the busiest, with 34 banded individuals, mostly of two early
migrant species: Tree Swallow (17) and Red-winged Blackbird (15). After this, things slowed down,
hovering around 10 species until May 5-7 when we had our next three busiest days: 33, 28, and 30
individuals banded respectively. This second peak of abundance was driven by the arrival of Gray
Catbirds (28 over 3 days), Eastern Towhee (8) and Baltimore Orioles (6), with these three species
representing 46% of bandings over that period. Banding rate fluctuated around 15 per day until May 17,
then slowly dropped until May 24, when we averaged less than 10 per day until the end of the season.
When we correct for effort and look at birds banded per 100 net hours, we see a very similar pattern:
abundance peaking on Apr-16, then again in early May before plateauing until late May, then declining.
Figure 2- Number of birds banded per 100 net hours at Wellfleet Bay Wildlife Sanctuary during Spring 2015 operations.
Blue line is daily captures, while the red line is a 3-day running average. Captures rates peaked around May 6th, then
slowly declined until the end of the season.
Species Makeup
With 65 species captured in Wellfleet in Spring 2015, the station showed a good level of diversity for
spring on Cape Cod. Species richness peaked on May 5 with 17 species, May 14 with 14 and May 6 with
12. We banded about 5 species a day for the rest of the season. This jumped to 5-10 species a day, with a
couple peaks in the teens generally corresponding with peaks in abundance. During the least week of the
season, the diversity dropped back down to ~5 species per day.
Figure 3- Number of species banded daily at Wellfleet Bay Wildlife Sanctuary during Spring 2015 operations.
Blue line represents daily species total, while the red line represents a running 3-day average.
Species richness peaked on May 5 with 17 species and decreased to ~5 species per day around by May 20.
When we correct for effort by looking at species banded per 100 net hours, we see a very similar pattern,
with richness peaking on May 23 at just under 34 species per 100 net hours (Fig. 4). At about 12 species
per 100 net hours, diversity was higher in the second half of the season than in the first half of the season,
when we averaged 10 per 100 net hours.
Figure 4- Number of species banded per 100 net hours at Wellfleet Bay Wildlife Sanctuary during Spring 2015
operations. Blue line represents daily species total, while the red line represents a running 3-day average.
Species richness peaked on May 5 and May 23 and was slightly higher for the second half of the season, before dropping
for the final 5 days.
Next, we will look at some of the more common
species encountered to further examine how the
sanctuary is used by different passerines. Table 1 lists
the top 20 most common species banded in Spring
2015. Diversity varied throughout the season, with
capture rates of individual species changing as the
season progressed. Some of the most common
species were year-round residents, with American
Goldfinch (63 captures), Black-capped Chickadee
(33) and Northern Cardinal (20) falling in the top 10,
and Blue Jay (10), Brown-headed Cowbird (5) and
House Finch (5) in the top 20. The rest of the Top 20
is dominated by summer breeders, starting with rank
#1 Gray Catbird (155) and 2 Tree Swallow (71) and
other breeding season-only species taking 13
additional slots in the Top 20. The only true migrants
(migrating through, but not breeding on the
Sanctuary) in the top 20 fall at the bottom of the list:
Magnolia Warbler (5) and Black-and-White Warbler
(4).
Table 1- Top 20 species banded at Wellfleet Bay
Wildlife Sanctuary in Spring 2015.
Species
1. Gray Catbird
2. Tree Swallow
3. American Goldfinch
4. Red-winged Blackbird
5. Black-capped Chickadee
6. Common Grackle
7. Baltimore Oriole
8. Northern Cardinal
9. Common Yellowthroat
10. Eastern Towhee
11. Pine Warbler
12. Chipping Sparrow
13. Blue Jay
14. American Robin
15. Orchard Oriole
15. Song Sparrow
17. Brown-headed Cowbird
17. House Finch
17. Magnolia Warbler
20. Black-and-white Warbler
20. Great-crested Flycatcher
Banded
155
71
63
38
33
24
21
20
18
17
12
11
10
9
6
6
5
5
5
4
4
When we look at the variation in common species
week by week, we see some patterns in the data. The
most common species banded (Gray Catbird) does
not appear until the third week, but is far and away
the most common capture once they arrive in Week 3
until the end of the season (Table 2). We see a similar
pattern with Chipping Sparrow, in smaller numbers,
as they are absent in week 1 but present on the list 4 out of the final 5 weeks. Same goes for Common
Yellowthroats, absent the first three weeks but in the top 10 the last three. American Goldfinches are
present every week, but peak in week 2 and 3 averaging 18.5 capture, at least double their totals for other
weeks. Black-capped Chickadees are also present in every period, but decline as some individuals leave
the Sanctuary to breed and others now banded only appear in the recapture data. Red-winged Blackbird
and Tree Swallows peak in the first two weeks, then decline as migration ends and residents settle onto
breeding territories, completely disappearing from the top captures list for the final two weeks. This
pattern is repeated with Pine Warblers in weeks 2 and 3, and Baltimore Orioles in weeks 3 and 4, as they
arrive in larger numbers, then settle on territories and begin avoiding the nets. Common Grackles, an
early migrant, were captured each week in small numbers, reflecting their abundance along Silver Spring.
Week 5 was our best week for migrant warbler diversity, with American Redstart, Magnolia Warbler and
Northern Waterthrush all appearing on the top 10, albeit in smaller numbers.
On the other end of the spectrum are the rarer birds, often captured only once per season. These birds may
not pass through the Sanctuary in large numbers or may be present but not captured often, but they still
shed light on habitat use. Species only banded once this year are: Black-throated Green Warbler, Cedar
Waxwing, Chestnut-sided Warbler, Eastern Kingbird, Indigo Bunting, Least Flycatcher, Louisiana
Waterthrush, Myrtle Warbler, Northern Mockingbird, Northern Parula, Purple Finch, Red-breasted
Nuthatch, Ruby-crowned Kinglet, Scarlet Tanager, Sharp-shinned Hawk, Tennessee Warbler, Veery,
White-crowned Sparrow, Yellow-bellied Flycatcher and Yellow-shafted Flicker.
There are a few captures that were especially interesting in terms of their rarity on the site or unlikeliness
in mist nets. We captured a single Louisiana Waterthrush on April 22. This species breeds in Western
Massachusetts and is a rare spring migrant on the Cape with only a handful of records in the last 10 years.
Tennessee Warblers, while not rare, usually migrate inland and are an uncommon species to encounter on
the coast. Recent outbreaks of spruce budworm in Eastern Canada have lead to a boom in this species and
probably contributed to our capture. Purple Finch is another fine capture, as this species is declining due
to habitat changes and being replaced locally and regionally by House Finches. The Wellfleet Bay
Sanctuary receives as much birdwatching attention as just about any other location on Cape Cod, but
without banding operations, these rare birds would most likely not have been documented in 2015.
Table 2- Most common species banded weekly at Wellfleet Bay Wildlife Sanctuary in Spring 2014.
Some species like Black-capped Chickadee and American Goldfinch are present throughout the
spring. Others are absent early but dominate numbers once they arrive: Gray Catbird, Eastern
Towhee, Common Yellowthroat. Some only appear briefly during a single week as their migration
through the station peaks: Northern Waterthrush, American Redstart, Magnolia Warbler (all in
week 5, May 17-24).
Week 1
15-22/Apr
1
2
3
4
5
6
7
8
9
10
11
12
TRES1
RWBL2
BCCH3
AMGO4
NOCA5
COGR6
AMRO7
SOSP8
36
15
14
9
6
5
2
2
Week 2
Week 3
23-30/Apr
AMGO
TRES
BCCH
PIWA9
RWBL
NOCA
COGR
BHCO10
BLJA11
CHSP12
WBNU13
17
16
7
5
5
4
3
2
2
2
2
1-8/May
GRCA14
AMGO
RWBL
EATO15
TRES
BAOR16
COGR
BCCH
BLJA
CHSP
NOCA
PIWA
37
20
14
13
13
8
6
5
4
4
4
4
Week 4
Week 5
9-16/May
GRCA
BAOR
COYE17
AMGO
BCCH
COGR
TRES
CHSP
RWBL
59
11
9
7
4
4
4
3
3
Week 6
17-24/May
25-31/May
GRCA
AMGO
MAWA18
BCCH
COYE
AMRE19
AMRO
COGR
NOCA
NOWA20
OROR21
TRES
GRCA
COYE
COGR
GCFL22
NOCA
AMGO
BLJA
CHSP
EATO
SOSP
37
8
4
3
3
2
2
2
2
2
2
2
22
5
4
3
3
2
2
2
2
2
Legend
1.
2.
3.
4.
5.
6.
7.
8.
9.
Tree Swallow
Red-winged Blackbird
Black-capped Chickadee
American Goldfinch
Northern Cardinal
Common Grackle
American Robin
Song Sparrow
Pine Warbler
10.
11.
12.
13.
14.
15.
16.
17.
18.
Brown-headed Cowbird
Blue Jay
Chipping Sparrow
White-breasted Nuthatch
Gray Catbird
Eastern Towhee
Baltimore Oriole
Common Yellowthroat
Magnolia Warbler
19.
20.
21.
22.
American Redstart
Northern Waterthrush
Orchard Oriole
Great-crested Flycatcher
Recaptures
There were 438 recaptures (birds captured while already fitted with a band), representing 234 unique
individuals of 30 species in Spring 2015. The volume of recaptures (438) compared to individuals banded
(596) represents a recap-to-banded ratio of ~3:4. This rate implies that individuals captured on site often
remain on site, leading to high recapture rates. This was of course influenced by the 142 Black-capped
Chickadee recaptures, representing 13% of total captures and a whopping 33% of recaptures! Recaptures
averaged 10 a day from April 15 through May 4, when the rate increased to more than 15 a day. The rate
dropped sharply after May 18 and then held steady around six a day until the end of the season. The two
highest recapture days were May 8 (23 recaptures) and May 17 (22), corresponding with the peaks of
abundance. Diversity of recaps follows a similar pattern, starting low at about 3 species per day, then
increasing as capture rate and diversity increased around May 8, plateauing around 7 species a day. The
rate then drops to 2-4 species daily starting May 18 and continues at this rate until the end of the season.
Figure 5- Individuals recaptured daily during Spring 2015 banding operations. The blue line represents the number of
recaptures daily and the red line represents the 3-day running average. Recaptures started around 10 per day, and
volume peaked in mid-May at 15-20 per day. Recapture rates began declining around May 20, settling around ~6 per day
until the end of the season.
Figure 6- Species recaptured daily during Spring 2015 banding operations. The blue line represents the number of species
recaptured daily and the red line represents the 3-day running average. Recapture diversity follows abundance closely,
starting low, then peaking from May 6th-29th before declining until the end of the season.
The majority of the recaptures were either year-round or breeding species (Table 3), with Black-capped
Chickadees (a year-round resident) alone representing 33% of recaptures. Gray Catbirds and Baltimore
Orioles are common summer breeders, and upon their arrival became very common recaptures. Eastern
Towhee, Orchard Oriole, Tree Swallow and Common Yellowthroat are common summer breeders. The
rest of the list is filled with year-round residents, however actual population make-up may change or
swell from summer to winter.
To get a full picture of recapture
rates, we need to look at how many
times each individual was
recaptured. The 142 Chickadees do
not represent 142 individuals, but
only 67 individuals recaptured a mean
of 2.12 times. Baltimore Orioles were
far and away the species most likely to
be recaptured multiple times, an
average of 3.5 times each, with the 42
recaptures only representing 12
individuals. These repeats are mostly
aggressive males that got caught
multiple times, often while chasing
other males. All other species rates
were between 1.14 and 2.33, indicating
the birds were captured a few times,
but generally avoided nets after the
initial capture.
Table 3- Top 15 species recaptured at Wellfleet banding station in Spring
2015 including their resident status. A recapture is each time a banded bird is
caught, so may represent multiple captures of the same individuals. This rate
of recapture is represented by the mean number of times an individual is
captured in the third column.
Species
1. Black-capped Chickadee
2. Gray Catbird
3. Baltimore Oriole
4. American Goldfinch
5. Eastern Towhee
6. Song Sparrow
7. Pine Warbler
8. American Robin
9. Northern Cardinal
10. Orchard Oriole
11. Tree Swallow
12. Downy Woodpecker
13. Tufted Titmouse
14. Field Sparrow
15. Common Yellowthroat
Recaps
Individuals
Mean
Recaps
Resident
Status
142
93
42
25
22
16
11
9
8
8
8
7
7
7
6
67
54
12
18
9
9
9
5
7
4
7
4
5
3
3
2.12
1.72
3.50
1.39
2.44
1.78
1.22
1.80
1.14
2.00
1.14
1.75
1.40
2.33
2.12
Year Round
Summer
Summer
Year Round
Summer
Year Round*
Summer
Year Round*
Year Round
Summer
Summer
Year Round
Year Round
Year Round*
Summer
In Spring 2015, we had 201 returns
(recaptures banded on site prior to
2015) of 96 individuals totaling 15 species. One of these returns was a single overwintering Whitethroated Sparrow; all other returns were species that breed on site. Black-capped Chickadee was our most
common return with 54 individuals captured 114 times. These were followed by six Gray Catbirds
captured 17 times, six Song Sparrows captured 10 times, five Tufted Timouses captured seven times and
four Downy Woodpeckers and four Eastern Towhees captured seven and 15 times respectively. Other
species with returns in 2015 were: American Robin (3), Chipping Sparrow (3), Field Sparrow (3), House
Finch (2), Northern Cardinal (2) Red-bellied Woodpecker (1), White-breasted Nuthatch and Blue Jay (1).
This high return rate is reflective of our high recapture rate at Wellfleet and reflects the quality of this
habitat for resident birds. As this project continues, we look forward to encountering more returns and
seeing some of these birds year after year.
* separate summer and winter populations may be present
We captured one truly exciting foreign recap in Spring 2015: a seventh year female Merlin. This bird was
captured in Net 3 (dormitory fields) on May 29. She had an old lock-on band and a pretty good bite.
Looking up her band number on the Bird Banding Lab page informed us that she was banded as a hatchyear bird at Kiptopeke Beach, State Park on the Eastern Shore of Virginia in Fall 2009. This was a great
first foreign recap. It will be hard to beat, but we look forward to even more exciting avian visitors in
future season, and maybe some of our birds showing up at other banding stations far afield.
Net Productivity
We assessed the productivity and usage of all nets (see map Appendix B) and summarized the data in
Table 4. Nets are placed along two loops, the Silver Spring Loop 1-5,7 and 16, and the Bay View Loop 915,17 and 61 (a 6m net). Nets fell into four broad habitats: semi-open field - Upland Fields (1,3,9,11,61),
freshwater mature forest/thicket along Silver Spring (2,4,5,7,16), dense Black Locust forest - the Maze
(10,12,15,17) and Saltmarsh Edge (13,14). Several nets were adjusted or closed before the start of Spring
2015 banding operations. Net 11 was rotated 90 degrees to better target birds moving through the field
and Net 2 lane was cut further into the woods and out of the field. Net 8 was closed as it was too close to
a bird feeder that was likely influencing its captures. It will not be reused in future seasons. Net 6 was
closed due to flooding and hopefully will be reopened with lower water levels in the fall.
Nets were a mix of new and used mist nets. All nets were 12x2.4m. Nets 14 and 6 were 30mm mesh, the
remaining nets were 36mm mesh. Nets 1, 15, 16 were used in good condition, the remainder of the nets
were unused but had spent a minimum of 10 years in storage. The quality and mesh size of the nets
appeared to impact capture rates as laid out in Heimerdinger and Leberman (1966). Larger passerines
such as Eastern Towhee and Gray Catbird as well as Cooper’s Hawk and Sharp-shinned Hawk were
captured more often, while smaller species like warblers, chickadees and sparrows were captured in
smaller numbers. Additionally, when the larger nets do capture small birds, they are more likely to
become entangled among the larger mesh. This effect is magnified in species (like Black-capped
Chickadees) that “fight” in the net, leading to an increased number of challenging and time consuming
extractions.
Table 4- Net effort and capture rates for newly banded and recaptures during Spring
2015 operations at Wellfleet Bay Wildlife Sanctuary.
Total
Banded
Recaptures
Captures /100 Net Hours /100 Net Hours
Net
Net hours
Banded
Recaps
1
208.23
19
25
50
9.10
11.98
2
189.39
46
40
90
24.29
21.12
3
154.74
59
44
107
36.94
27.54
4
203.23
50
42
95
24.55
20.62
5
215.72
50
32
86
23.08
14.77
7
203.39
95
36
133
46.91
17.78
9
177.06
106
22
132
58.08
12.05
10
204.90
43
36
81
20.94
17.53
11
114.63
6
13
19
4.78
10.37
12
170.90
22
22
45
12.48
12.48
13
124.22
13
21
35
9.66
15.61
14
139.87
9
32
42
6.20
22.04
15
205.87
12
15
28
5.83
7.29
16
207.89
43
43
90
20.12
20.12
17
129.56
7
6
13
5.40
4.63
61*
49.04
2698.64
13
596
5
438
19
1073
26.51
21.58
10.20
15.79*
Total
*6m net
The net hours (effort) varied greatly among nets from 130 hours at Net 17 to 208 hours at Net 1. Several
factors contributed to these differences. First, nets were added after the start of the season to increase our
effort and refine our targeting of particular habitats: Net 17 in The Maze on April 30 and Net 61 a 6m net
in the Upland Fields on April 29. Net 61 was shut down on May 19 when a Northern Cardinal nest was
found in the tree adjacent and was not reopened before the season ended.
Nets could also be closed piecemeal in reaction to weather conditions, generally wind, but also
occasionally rain or cold. The Upland Field (1,3,9,11) and Saltmarsh Edge nets (13,14) were the most
exposed and therefore most affected by wind and rain. Finally, nets were to be closed if the volume of
birds captured became too much to handle, which did not occur in Spring 2015.
Nets by Habitat
The banding station is composed of a mix of habitats attracting a diverse collection of bird species. Some
common captures like Gray Catbird, American Goldfinch, Eastern Towhee, Baltimore Oriole, Northern
Cardinal and Black-capped Chickadee were present in all habitats, with chickadees occupying a Top 3
position in each habitat (Table 5). Other species like Common Grackle and Red-winged Blackbirds
primarily occur in a single habitat, with 59 out of 63 (94%) of captures in Silver Spring.
Table 5- Four major habitats represented at Wellfleet Bay Wildlife Sanctuary, including the most common species
captured in nets in each habitat during Spring 2015 operations:
a) Upland Fields- dry brushy open fields
b) Silver Spring- mature mixed fresh water riparian forest
c) Maze- dense secondary growth dry black locust forest d) Saltmarsh Edge- brushy saltmarsh edge
a) Upland Fields: Nets 1,9,11,61
Species
1. Tree Swallow
2. B. C. Chickadee
3. Gray Catbird
4. Am. Goldfinch
5. Baltimore Oriole
6. Pine Warbler
7. Eastern Towhee
8. Chipping Sparrow
9. Orchard Oriole
10. Northern Cardinal
11. R.T. Hummingbird
Banded
76
62
50
36
11
10
8
6
6
5
5
c) The Maze: Nets 10,12,15,17
Species
1. Gray Catbird
2. B. C. Chickadee
3. Am. Goldfinch
4. Eastern Towhee
5. Chipping Sparrow
6. Field Sparrow
7. Northern Cardinal
8. Baltimore Oriole
9. Com. Yellowthroat
10. Pine Warbler
11. Gr-crested Flycat.
Banded
45
20
18
17
9
7
7
5
5
5
4
b) Silver Spring: Nets 2,4,5,7,16
Species
1. Gray Catbird
2. B. C. Chickadee
3. Baltimore Oriole
4. R. W. Blackbird
5. Common Grackle
6. Am. Goldfinch
7. American Robin
8. Eastern Towhee
9. Northern Cardinal
10. Com. Yellowthroat
11. Song Sparrow
Banded
151
63
48
37
25
22
15
13
13
11
11
d) Saltmarsh Edge: Nets 14,15
Species
1. B. C. Chickadee
2. Am. Goldfinch
3. Com. Yellowthroat
4. Song Sparrow
5. Pine Warbler
6. Gray Catbird
7. Blue Jay
8. Chipping Sparrow
9. Eastern Towhee
10. Northern Cardinal
Banded
32
12
7
6
5
4
2
2
2
2
Common Yellowthroats were well represented in all habitats except the Upland Field, while Chipping
Sparrows and Pine Warblers were common in all habitats except Silver Springs. Ruby-throated
Hummingbirds and Orchard Oriole were only represented in Upland Fields, Great-crested Flycatcher only
in The Maze, and Blue Jays only in the Saltmarsh edge (although in the case of Orchard Oriole and Blue
Jay, this is probably a result of sampling error). In upcoming seasons, as sample sizes increases, we will
gain a better picture of spring habitat use.
Habitat Selection by Migrants
The resident status of songbirds at Wellfleet Bay can be broadly separated into 4 categories: 1) Yearround Resident - present on Cape Cod 12 months of the year (individuals present seasonally may be from
different populations), 2) Summer Breeder - present as summer breeder only and absent in winter 3)
Winter Resident - present only in nonbreeding season and overwintering on Cape Cod, 4) Migrant present only in spring or fall migration, neither breeding nor wintering on Cape Cod. Our biggest interest
is how the birds in the migrant category are using habitats on the Sanctuary. In Spring 2015, we caught 16
migrants a total of 17 times.
Table 6- Number of migrant captures per habitat
and net loop during Spring 2015 banding operations
at Wellfleet Bay Wildlife Sanctuary. Migrants are
defined as birds ONLY present during migration,
not breeding or overwintering on Cape Cod.
Migrants appeared to favor the Silver Spring habitat
during spring migration, with 2/3 of captures occurring
in this habitat (Table 6). We captured four migrants in
the Upland Field nets, two along Silver Spring Trail and
two along Bay View Trail. The last two migrant
Habitat
Migrant Captures
Net Loop
captures were in The Maze, with no migrants captured
Upland Fields
4
B. View/S. Sp.
in the Saltmarsh Edge nets. 14 out of 18 migrants were
The Maze
2
Bay View
captured along the Silver Spring, showing a great
Saltmarsh Edge
0
Bay View
preference for this area. With net effort being
Silver Spring
12
Silver Spring
essentially equal between the two loops, this appears to
be a legitimate preference among migrants for the more inland Silver Springs Loop. This is in direct
contradiction to our findings in Fall 2014, when Bay View Trail was preferred, accounting for 80% of
migrant captures while only accounting for 20% of net effort. Silver Spring Trail’s more protected and
warmer inland location is probably more conducive to insect activity in the spring, while the abundance
of edge habitat along the Bay View trail is preferred in the fall. It will be interesting to see if this pattern
continues in future seasons.
Summary
The 2015 season was a great start to the reopening of spring banding at Wellfleet Bay Wildlife Sanctuary.
Good weather allowed for a strong effort, as we only had three days in which we could not open nets.
However, the wind associated with the Outer Cape did have a large impact early in the season, as there
were no leaves to cut the wind. Most of our captures were limited to local breeders or migrants breeding
in habitats similar to the station, with a sprinkling of more migrants to keep things interesting.
Overlapping with the start of breeding also provides some good data on the timing of species breeding
locally. While we are already gathering interesting findings on habitat use by land birds on the Sanctuary,
it will only become more useful as we collect more data and consistent patterns begin to emerge. Our
outreach efforts reached new heights this spring with many organized visits by paid groups, students of all
ages and donors alike. These visits went very well and our outreach efforts are paying dividends for all
parties involved, educating the public and giving them the unique experience of seeing songbirds up
close. This research belongs in a much wider scientific effort at the Sanctuary and by Mass Audubon, and
we are very pleased to contribute to these endeavors, content in the knowledge that our research will be
combined with other findings to help influence conservation action and policy.
Moving Forward
We had a wonderful first spring banding season in 2015, as we had a nice collection of captures and many
wonderful opportunities for public outreach. All of our group visits went well and we introduced a lot of
folks to bird banding in the hope of increasing their understanding and empathy for these animals. We
look forward to building on our successes in Fall 2015 and beyond, improving both the quality of our data
collection and the volume and impact of our outreach efforts.
The first and most important improvement for Fall 2015 is to purchase an entire new collection of 18 (16
active, two replacements) mist nets, all 32mm mesh size. This will reduce the number of tangled birds and
challenging extractions, making the station safer for birds and more efficient to run while putting our
effort more in line with other banding stations, most of which use 32mm nets for constant effort banding.
Further refinement of our net placement can improve our data collection on habitat use and raise the
capture rate of the station in general. To accomplish this, I suggest placing a two tier net at the Net 6
location, allowing us to operate safely over the water. Also adding 6m net to the pier between Nets 4 and
16 will result in the capture of birds moving along the edge of the vegetation, over the water of Silver
Spring and beyond the reach of our current nets.
We must also work to increase the volume and quality of our outreach activities. We were disappointed
by the number of paid banding demonstration groups at the station this spring and hope to improve on this
in future seasons. Organizing visits twice a week may work better in the fall than in the spring, with better
weather and more visitors on the Cape. Also, the longer the station is established, the more it will be
known among the Mass Audubon audience. Increased visibility should help drive attendance. One way to
further target our audience is to start a banding Twitter feed on Mass Audubon’s account. By listing the
interesting captures mid-morning each day, we can keep our station in people’s mind and hopefully
encourage visits to the Sanctuary. Organized school and donor groups were a huge hit this spring.
Feedback from educators and fundraisers is universally positive and we hope to expand and refine these
visits in upcoming seasons.
Acknowledgements
First and foremost, we thank our skilled and dedicated banders for their hard work and perseverance
through the spring. Thank you Aya Rothwell, Jennifer Froehly, Kaitlin Pizzi and Mary-Lou Heintz for
making daily operation of the station possible and enjoyable. Thanks to everyone at the sanctuary, but
especially Mark Faherty and Bob Prescott for helping to keep the station funded and operational, to
Jenette Kerr for spreading our pictures across the internet and to Annie Hooper, Jessica MacManus and
Spring Buckhorn for leading all the excited groups out to see the birds. Of course, we appreciate all the
help from the Sanctuary volunteers and staff, too many to name, but thanks to you all the same. Thanks to
Valerie Bourdeau and the Junda family for all the support on Cape Cod and beyond. And finally, to all the
classes and visitors who came to the station, we are always happy to see you and share our love of these
birds.
References
Austin, Oliver L., M.D., 1932. “The Austin Ornithological Research Station,” Bird Banding, Volume 3,
No. 2 Page 51 – 62.
Clench, Mary H. and J. William Hardy, 1989. “In Memoriam: Oliver L. Austin Jr.” The Auk, Number
106, page 706 – 723.
Heimerdinger, M. A. & Leberman, R. C. 1966. The comparative efficiency of 30 and 36 mm. mesh in
mist nets. Bird-banding, 280-285.
Appendix A- Map of Wellfleet Wildlife Sanctuary Banding Station
Figure 7- Map of Wellfleet Banding Station in Spring 2014, including all net locations and central banding station.
Bay View
Loop
Silver Spring
Loop