Cape May Raptor Banding Project
40+ Years of Conservation through Banding
Cape May Raptor Banding Project, Inc.
Cape May, NJ, U.S.A.
CapeMayRaptors.org
September 24, 2010
1
Introduction
We have operated a raptor banding station every year
since 1967 near Cape May, New Jersey, U.S.A. In 1999 we
incorporated as the Cape May Raptor Banding Project,
Inc. (CMRBP), a 501c3 non-profit organization run entirely
by volunteers. As of 2009 the project had captured about
132,000 diurnal raptors of 16 species during fall migration
in the months of September, October and November.
This makes CMRBP the largest raptor banding project in
North America and one of the largest in the world.
2
Location of the
Cape May Raptor
Banding Project
3
Methods
From one to five banding stations have been operated
annually at CMRBP using a combination of bow traps,
mist nets and dho-gaza traps employing live rock pigeons,
starlings and house sparrows as lures. Trapping methods
have been described previously (Clark 1970, 1976, 1981).
Habitats at stations range from agricultural fields and
meadows to scrub-shrub to tidal and non-tidal wetlands.
Blinds and trap/net arrays are generally oriented towards
the north and/or east to take advantage of typical flight
lines at Cape May.
4
Overall Banding Results
Datasets maintained by the project include birds first
banded at Cape May (bandings), Cape May-banded birds
that return to Cape may in subsequent years (returns),
encounters elsewhere of birds originally banded at Cape
May (recoveries), and birds originally banded elsewhere
that are encountered at Cape May (foreign recoveries).
Most raptors captured at Cape May have been unbanded;
fewer than 300 of the total of 132,000 have been foreign
recoveries, and only about 45 captures have been
returns.
5
Slightly more than half of the birds captured at Cape May
have been Sharp-shinned Hawks (Accipiter striatus).
Cooper’s Hawk (A. cooperii) and American Kestrel (Falco
sparverius) together constitute another 30% of the total;
no other single species represents more than 7%.
6
Bandings by Species
Species
Percent of Total (n = 131,717)
Sharp-shinned Hawk
52.9 (n = 68,892)
Cooper’s Hawk
16.3 (n = 22,452)
American Kestrel
13.7 (n = 17,760)
Merlin
6.4 (n = 8,474)
Red-tailed Hawk
5.8 (n = 7,644)
Northern Harrier
2.8 (n = 3,644)
Peregrine Falcon
1.2 (n = 1,694)
Red-shouldered Hawk
0.3 (n = 390)
Northern Goshawk
0.3 (n = 375)
Broad-winged Hawk
0.2 (n = 316)
Golden Eagle
<0.1 (n = 21)
Swainson’s Hawk
<0.1 (n = 18)
Osprey
<0.1 (n = 17)
Rough-legged Hawk
<0.1 (n = 9)
Bald Eagle
<0.1 (n = 6)
Eurasian Kestrel
<0.1 (n = 1)
7
Annual totals for all species have topped 5,000 birds on
five occasions, the last time occurring in 1987. The
decline in annual totals since the 1970’s and 1980’s is due
to sharp decreases in numbers of Sharp-shinned Hawks
and American Kestrels.
8
All Bandings by Year
6000
5000
Number Banded
4000
3000
2000
R² = 0.8367
1000
0
9
Highlights include the second North American record of
Eurasian Kestrel (F. tinnunculus) (Clark 1974a), and
confirmation of the occurrence of Swainson’s Hawk
(Buteo swainsonii) in New Jersey (Clark 1974b).
10
Long Term Trends
Long term trends in banding numbers at Cape May show
a variety of patterns. These may indicate actual changes
in populations, but could also reflect shifts in migration
pathways. Such shifts could result from year-to-year
irregularities in weather, the influence of natural
succession or increased residential development on the
Cape May Peninsula, or other factors.
11
Banding numbers have been demonstrated to correlate
closely with similar trends in Cape May Hawk Watch
counts for Northern Harrier (Schultz 1996). Numbers of
birds banded appear to track Cape May count trends for
other species too, including declines in Sharp-shinned
Hawk and American Kestrel since the 1970’s and 1980’s,
and increases in Cooper’s Hawk and Peregrine Falcon
(Falco peregrinus) over the last 30-35 years (Bildstein, et
al 2008).
12
2500
2000
Number Banded
Sharp-shinned Hawk Bandings by Year
4500
4000
3500
3000
1500
1000
500
0
2009
2007
2005
2003
2001
1999
1997
1995
1993
1991
1989
1987
1985
1983
1981
1979
1977
1975
1973
1971
1969
1967
13
1500
1000
Number Banded
American Kestrel Bandings by Year
2500
2000
500
0
2009
2007
2005
2003
2001
1999
1997
1995
1993
1991
1989
1987
1985
1983
1981
1979
1977
1975
1973
1971
1969
1967
14
1000
800
600
Number Banded
Cooper's Hawk Bandings by Year
1600
1400
1200
400
200
0
2009
2007
2005
2003
2001
1999
1997
1995
1993
1991
1989
1987
1985
1983
1981
1979
1977
1975
1973
1971
1969
1967
15
80
60
Number Banded
Peregrine Falcon Bandings by Year
140
120
100
40
20
0
2009
2007
2005
2003
2001
1999
1997
1995
1993
1991
1989
1987
1985
1983
1981
1979
1977
1975
1973
1971
1969
1967
16
Age and sex ratios
Of those that could be aged, 94% of birds banded were
aged by plumage as juveniles (hatch year), while only
0.6% were definitively aged as full adults (after second
year). Sex ratios frequently deviate from 1:1, with some
species, such as Cooper’s Hawk, Northern Goshawk and
Northern Harrier, showing ratios of nearly 2:1. Sex ratios
of recoveries vary from those of bandings, with no
discernable relationship between the two.
17
Percent Female Bandings vs. Recoveries by Species
Species
Bandings
Recoveries
Northern Goshawk
27.3
46.2
Cooper’s Hawk
33.3
47.9
Northern Harrier
36.3
55.9
American Kestrel
52.2
46.9
Peregrine Falcon
56.2
70.4
Merlin
57.0
62.8
Sharp-shinned Hawk
59.8
74.1
18
Migration Timing
Generally, falcon captures peak in late September;
accipiters, with the exception of Northern Goshawk (A.
gentilis), in mid-October; and buteos, chiefly Red-tailed
Hawk (B. jamaicensis), in early November.
19
Migration Timing of Falcons, Accipiters and Buteos
3000
Falcons
Accipiters
Buteos
11 October
2500
Number Banded
2000
1500
30 September
3 November
1000
500
0
9-Dec
2-Dec
25-Nov
18-Nov
11-Nov
4-Nov
28-Oct
21-Oct
14-Oct
7-Oct
30-Sep
23-Sep
16-Sep
9-Sep
2-Sep
26-Aug
19-Aug
20
Within most species, seasonal timing of captures differs
noticeably by age class, with juveniles peaking before
adults. The statistical significance of this difference at
Cape May has been confirmed for Northern Harrier
(Circus cyaneus) (Bildstein et al 1984) and holds true for
other species as well.
21
Migration Timing of Northern Harrier by Age Class
90
HY
AHY+
12 October
80
70
Number Banded
60
31 October
50
40
30
20
10
0
4-Dec
25-Nov
18-Nov
11-Nov
4-Nov
28-Oct
21-Oct
14-Oct
7-Oct
30-Sep
23-Sep
16-Sep
9-Sep
2-Sep
22
Migration Timing of Sharp-shinned Hawk by Age Class
2500
HY
AHY+
11 October
Number Banded
2000
1500
1000
500
0
9-Dec
1-Dec
24-Nov
17-Nov
10-Nov
3-Nov
27-Oct
20-Oct
13-Oct
6-Oct
29-Sep
22-Sep
15-Sep
8-Sep
31-Aug
23
Migration Timing of Red-tailed Hawk by Age Class
350
HY
AHY+
300
3 November
Number Banded
250
200
150
10 November
100
50
0
12-Dec
4-Dec
27-Nov
20-Nov
13-Nov
6-Nov
30-Oct
23-Oct
16-Oct
9-Oct
2-Oct
25-Sep
18-Sep
11-Sep
4-Sep
27-Aug
24
Migration Timing of American Kestrel by Age Class
800
HY
AHY+
700
600
Number Banded
29 September
500
400
300
10 October
200
100
0
27-Nov
19-Nov
12-Nov
5-Nov
29-Oct
22-Oct
15-Oct
8-Oct
1-Oct
24-Sep
17-Sep
10-Sep
3-Sep
25-Aug
25
Differences in timing by sex are less consistent. Analysis
of Cape May data shows that females migrate earlier
than males for Merlin (Falco columbarius) (Clark 1985).
This is partially or completely true for Sharp-shinned
Hawk, Cooper’s Hawk and American Kestrel as well.
However, this tendency is reversed for Northern Harrier
(Bildstein et al 1984), where males migrate first.
26
Migration Timing of Merlin by Sex
300
F
28 September
M
29 September
250
Number Banded
200
150
100
50
0
19-Nov
11-Nov
4-Nov
28-Oct
21-Oct
14-Oct
7-Oct
30-Sep
23-Sep
16-Sep
9-Sep
1-Sep
27
Migration Timing of Sharp-shinned Hawk by Sex
1600
F
M
1400
11 October
Number Banded
1200
1000
800
600
400
200
0
9-Dec
1-Dec
24-Nov
17-Nov
10-Nov
3-Nov
27-Oct
20-Oct
13-Oct
6-Oct
29-Sep
22-Sep
15-Sep
8-Sep
31-Aug
28
Migration Timing of Cooper's Hawk by Sex
700
F
M
10 October
600
Number Banded
500
400
11 October
300
200
100
0
4-Dec
27-Nov
20-Nov
13-Nov
6-Nov
30-Oct
23-Oct
16-Oct
9-Oct
2-Oct
25-Sep
18-Sep
11-Sep
4-Sep
28-Aug
29
Migration Timing of American Kestrel by Sex
400
F
M
26 September
350
300
Number Banded
3 October
250
200
150
100
50
0
27-Nov
19-Nov
12-Nov
5-Nov
29-Oct
22-Oct
15-Oct
8-Oct
1-Oct
24-Sep
17-Sep
10-Sep
3-Sep
25-Aug
30
Migration Timing of Northern Harrier by Sex
70
F
M
60
13 October
Number Banded
50
40
30
20
10
19 October
0
4-Dec
25-Nov
18-Nov
11-Nov
4-Nov
28-Oct
21-Oct
14-Oct
7-Oct
30-Sep
23-Sep
16-Sep
9-Sep
2-Sep
31
Summary of Recoveries
About 2,500 Cape May-banded birds (2%) have been
encountered subsequently at other locations throughout
the Americas at all times of the year. Most recoveries are
from the Eastern U.S. and the Canadian Maritimes,
although there are some records from the West Indies
and Central and South America.
32
Recoveries of Cape
May-banded birds
33
Encounter frequencies differ from capture rates in most
species, with larger species encountered relatively more
often than smaller species. This is probably the result of
an increased probability of detection of larger birds.
34
Percent Bandings vs. Recoveries by Species
Species
Percent of Total Bandings
Percent of Bandings Recovered
Golden Eagle
<0.1
9.5
Osprey
<0.1
5.9
Red-tailed Hawk
5.8
4.6
Northern Goshawk
0.3
3.5
Swainson’s Hawk
<0.1
5.6
Peregrine Falcon
1.2
9.4
Red-shouldered Hawk
0.3
1.3
Northern Harrier
2.8
1.0
16.3
3.1
Broad-winged Hawk
0.2
2.5
Merlin
6.4
1.7
Sharp-shinned Hawk
52.9
1.4
American Kestrel
13.7
1.4
Cooper’s Hawk
35
Movements
Mapping of encounter locations shows that summer
ranges – and therefore, presumably, breeding areas – for
many species are primarily northeast of Cape May.
36
Summer recoveries of
Sharp-shinned Hawk
37
Summer recoveries
of Cooper’s Hawk
38
Summer recoveries
of Red-tailed Hawk
39
Summer recoveries
of Merlin
40
Summer recoveries of
American Kestrel
41
Mapping also demonstrates possible seasonal differences
in migration pathways, and possible differences between
sexes in breeding and wintering ranges, for some species.
For example, Sharp-shinned Hawks and Cooper’s Hawks
appear to migrate further inland in the spring than in the
autumn, and female Cooper’s Hawks winter further
south, on average, than males.
42
Spring and Autumn
recoveries of Sharpshinned Hawk
43
Spring and Autumn
recoveries of
Cooper’s Hawk
44
39.17°
37.98°
Winter
recoveries of
Cooper’s Hawk
45
Finally, about 6% of recoveries were made north or west
of Cape May within several weeks of the banding date,
indicating that fall migration does not always progress
steadily southward.
46
Same-season
recoveries north of
Cape May
47
Longevity
Longevity records for raptors banded at Cape May,
derived from recoveries, include 24 yrs for Red-tailed
Hawk, 15 yrs for Northern Harrier, Sharp-shinned Hawk
and Cooper’s Hawk, and nearly 14 yrs for Broad-winged
Hawk (B. platypterus).
48
Longevity Records by Species
Species
Red-tailed Hawk
Longevity
24 yrs
Sharp-shinned Hawk
15 yrs, 6 mos
Cooper’s Hawk
15 yrs, 3 mos
Northern Harrier
Broad-winged Hawk
Peregrine Falcon
15 yrs
13 yrs, 10 mos
11 yrs
Merlin
10 yrs, 9 mos
American Kestrel
7 yrs, 6 mos
Red-shouldered Hawk
5 yrs, 5 mos
Northern Goshawk
3 yrs, 11 mos
Golden Eagle
2 yrs, 2 mos
49
Mortality
Of encounters listing a specific cause of mortality,
collisions with moving vehicles account for about 30%
and collisions with stationary objects about 25%.
50
Causes of Mortality by Species
Cause
NOHA SSHA COHA NOGO RTHA RSHA SWHA BWHA GOEA PEFA MERL AMKE OSPR Total
Struck by moving
vehicle/ Dead on
2
33
61
0
50
1
0
3
0
3
7
23
0
183
highway
Struck stationary
1
98
35
1
5
0
0
0
0
0
7
5
0
152
object
Injury
1
15
24
0
8
0
0
0
0
2
10
6
1
67
Shot
4
18
0
1
10
0
0
0
0
3
21
5
0
62
Inside building
0
4
6
0
2
0
0
0
0
1
1
11
0
25
Caught by hand
0
6
2
0
4
0
0
0
0
0
2
2
0
16
Caught by cat
0
8
0
0
0
0
0
0
0
0
1
3
0
12
Struck wires
0
3
3
0
3
0
0
0
0
0
0
1
0
10
Caught by dog
1
3
2
0
1
0
0
0
0
0
1
0
0
8
Entanglement
0
3
1
0
1
0
0
0
0
0
1
0
0
6
Caught by raptor
0
2
1
0
1
0
0
0
0
1
0
1
0
6
Struck by train
0
0
2
0
3
0
0
0
0
0
0
0
0
5
Disease
0
1
0
0
0
0
0
0
0
1
0
3
0
5
Caught by other
1
0
2
0
2
0
0
0
0
0
0
0
0
5
animal
Caught by trap
0
0
1
0
0
0
0
1
0
0
1
2
0
5
All others known
1
4
0
0
2
0
0
0
0
0
0
4
0
11
Unknown
15
422 370
7
171
4
1
2
2
13
41
95
0
1143
Total
26
620 510
9
263
5
1
6
2
24
93
161
1
1721
51
Morphometrics
Morphometric data – primarily mass and wing chord –
have been collected for tens of thousands of individuals.
Comparison with measurements from other raptor
migration banding stations shows regional variations
within some species, with many western birds having
lower mass but longer wings and/or tails than eastern
conspecifics (Smith et al 1990).
52
Mass and Wing Chord Measurements for Selected Species
Species
Northern Harrier
Male
Female
Sharp-shinned Hawk
Male
Female
Cooper's Hawk
Male
Female
Northern Goshawk
Male
Female
Red-tailed Hawk
Red-shouldered Hawk
Broad-winged Hawk
Peregrine Falcon
Male
Female
Merlin
Male
Female
American Kestrel
Male
Female
Wing Chord
Mass
296 - 362 mm (avg. 331)
324 - 398 mm (avg. 372)
279 - 406 g (avg. 336)
400 - 651 g (avg. 488)
158 - 173mm (avg. 166)
185 - 215mm (avg. 198)
86 - 131g (avg. 101)
145 - 202g (avg. 167)
217 - 238mm (avg. 228)
251 - 272mm (avg. 263)
300 - 424g (avg. 343)
449 - 601g (avg. 525)
300 – 335mm (avg. 317)
332 – 361mm (avg. 346)
337 - 410mm (avg. 371)
302 - 344mm (avg. 322)
233 - 301mm (avg. 274)
677 - 1014g (avg. 774)
758 - 1214g (avg. 1000)
696 - 1649g (avg. 1045)
460 - 930g (avg. 653)
308 - 483g (avg. 396)
305 - 331mm (avg. 319)
342 - 376mm (avg. 362)
496 - 782g (avg. 578)
590 - 1042g (avg. 831)
178 - 197mm (avg. 189)
195 - 220mm (avg. 209)
132 - 183g (avg. 155)
176 - 254g (avg. 213)
165 - 194mm (avg. 183)
172 - 203mm (avg. 191)
97 -150g (avg. 122)
90 -144g (avg. 109)
53
Abnormalities
Although the vast majority of birds captured at Cape May appear
entirely normal, various abnormalities have been noted. These
include supernumerary flight feathers (Clark et al 1988), and
assorted injuries and deformities.
54
Merlin with 13 tail
feathers, one more
than the normal 12
55
Collaborative Research
CMRBP has long made captured birds available to other
researchers. Collaborators have studied local movements,
parasites, contaminants and taxonomy. Among their findings
are support for the counting methodology used by the Cape May
Hawk Watch (Holthuijzen and Oosterhuis 1985); the presence of
hematozoans in nearly 60% of birds examined (Kirkpatrick and
Lauer 1985); and genetic confirmation of subspecies
classification in Red-tailed Hawk (Pearlstine 2004). Current
research projects include levels of mercury contamination in
various species and population genetics of Merlin subspecies.
56
Education
Tens of thousands of people have attended educational
programs, featuring banded raptors, that emphasize natural
history and conservation. The audience is given an introduction
to the history and operation of the banding project, and to the
raptor migration phenomenon at Cape May. Key facts and
figures about project statistics and findings are also related.
Finally, the biology, ecology and conservation status of each
species present are discussed and the birds are then released in
front of the audience.
57
Golden Eagle at an
educational program
58
Acknowledgements
•Many raptor banders and helpers, especially Chris Schultz, Sam
Orr and Ray Miller
•Marlene Miller for data entry
•Cape May Bird Observatory/New Jersey Audubon, National
Wildlife Federation and U.S. Fish & Wildlife Service for support
during the initial stages of the project
59
References Cited and Other
Literature Utilizing CMRBP Data
Anderson, D., A.M.A. Holthuijzen, and L. Oosterhuis. 1980. A pilot telemetry study on
the migration movements of female Sharp-shinned Hawks at Cape May, New Jersey.
Technical Report, Department of Fisheries and Wildlife Sciences. Virginia Polytechnic
Institute and State University, Blacksburg.
Bildstein, K.L., W.S. Clark, D.L. Evans, M. Field, L. Soucy, and E. Henckel. 1984. Sex and
age differences in fall migration of Northern Harriers. J. Field Ornithology 55:143–150.
Bildstein, K.L., J.P. Smith, E. Ruelas I., and R.R. Veit (eds). 2008. State of North
America’s Birds of Prey. Nuttall Ornithological Club and American Ornithologists Union
Series in Ornithology No. 3. Cambridge, Massachusetts, and Washington, D.C. 466 pp.
Bolgiano, N.C. 2006. Was the rise and fall of eastern Sharp-shinned Hawk migration
counts linked to the 1970s spruce budworm infestation? Hawk Migration Studies 31:
9-14.
60
Clark, W.S. 1969. Migration trapping of hawks at Cape May, N.J. – second year. EBBA
News 32:69-76.
Clark, W.S. 1970. Migration trapping of hawks (and owls) at Cape May, N.J. - third
year. EBBA News 33: 181-190.
Clark, W.S. 1972. Migration trapping of hawks (and owls) at Cape May, N.J. - fifth year.
EBBA News 35: 121-131.
Clark, W.S. 1973. Cape May Point raptor banding station - 1972 results. EBBA News
36: 150-165.
Clark, W.S. 1974. Second record of the Kestrel (Falco tinnunculus) for North America.
Auk 91: 172.
Clark, W.S. 1974. Cape May Point raptor banding station - 1973 results. EBBA News
37: 51-64.
Clark, W.S. 1974. Occurrence of Swainson's Hawk substantiated in New Jersey.
Wilson Bulletin 86: 284-285.
61
Clark, W.S. 1976. Cape May Point Raptor Banding Station - 1974 Results. North
American Bird Bander 1:5-13.
Clark, W.S. 1981. A modified dho-gaza trap for use at a raptor banding station. J.
Wildlife Management 45: 1043-1044.
Clark, W.S. 1985. Migration of the Merlin along the coast of New Jersey. J. Raptor
Research 19:85–93.
Clark, W.S. 1985. The migrating Sharp-shinned Hawk at Cape May Point: banding and
recovery results. Pages 137-148 in M. Harwood, ed. Proceedings of hawk migration
conference IV. Hawk Migration Association of North America, Washington Depot, CT
U.S.A.
Clark,W.S., K. Duffy, E. Gorney, M. McGrady, and C. Schultz. 1988. Supernumerary
primaries and rectrices in some Eurasian and North American raptors. J. Raptor
Research 22: 53-58.
Clark, W.S., C. Schultz, and O. Allen. 2000. Conservation of migrating raptors through
banding; results of over 30 years of the Cape May Point Raptor Banding Project. In:
Raptors at Risk. World Working Group on Birds of Prey, London and Berlin.
62
Dunne, P.J. and W.S. Clark. 1977. Fall hawk movement at Cape May Point, New Jersey
- 1976. Occasional Paper No. 130, New Jersey Audubon 3: 114-124.
Henny, C. J., and W.S. Clark. 1982. Measurements of fall migrant Peregrine Falcons
from Texas and New Jersey. J. Field Ornithology 53: 326-332.
Holthuijzen, A.M.A . and L. Oosterhuis. 1981. Migration patterns of female Sharpshinned Hawks (Accipiter striatus) at Cape May Point, New Jersey. Technical Report,
Department of Fisheries and Wildlife Sciences. Virginia Polytechnic Institute and State
University, Blacksburg.
Holthuijzen, A.M.A., and L. Oosterhuis. 1985. Implications for migration counts from
telemetry studies of Sharp-shinned Hawks (Accipiter striatus) at Cape May Point, New
Jersey. Pages 305-312 in M. Harwood (ed.). Proc. Hawk Migration Conference IV,
Hawk Migration Association of North America, Lynchburg, VA.
Holthuijzen, A.M.A ., L. Oosterhuis, and M.R. Fuller. 1985. Habitat used by migrating
Sharp-shinned Hawks (Accipiter striatus) at Cape May Point, New Jersey, U.S.A. In I.
Newton and R.D. Chancellor, eds. Conservation Studies on Raptors. Based on the
Proceedings of the Second World Conference on Birds of Prey, held in Thessaloniki,
Greece, April 1982. International Council for Bird Preservation Technical Publication
No. 5.
63
Hull, J.M. and D.J. Girman. 2005. Effects of Holocene climate change on the historical
demography of migrating Sharp-shinned Hawks (Accipiter striatus velox) in North
America. Molecular Ecology 14:159-170.
Kirkpatrick, C.E. and D.M. Lauer. 1985. Hematozoa of raptors from southern New
Jersey and adjacent areas. J. Wildlife Disease 21: 1-6.
Kirkpatrick, C.E. and V.P. Trexler-Myren. 1986. A survey of free-living falconiform birds
for Salmonella. J. Amer. Veterinary Medical Assoc. 189:997-998.
Mueller, H.C., N.S. Mueller, D.D. Berger, G. Allez, W. Robichaud, and J.L. Kaspar. 2000.
Age and sex differences in the timing of fall migration of hawks and falcons. Wilson
Bull. 112:214–224.
Pearlstine, E.V. 2004. Variation in mitochondrial DNA of four species of migratory
raptors. J. Raptor Research 38:250-255.
Pearlstine, E.V., and D.B. Thompson. 2004. Geographic variation in morphology of
four species of migratory raptors. J. Raptor Research 38:34-342.
Schultz, C.W. 1994. Osprey captures tethered rock dove. North American Bird Bander
19:56-57.
64
Schultz, C.W. 1994. AFR: Cape May Raptor Banding Project - 1993 Yearly Report.
North American Bird Bander 19:34-35.
Schultz, C.W. 1996. Cape May Raptor Banding Project 1995 Yearly Report. North
American Bird Bander 21:35-37.
Schultz, C.W. 1996. Migration trend and morphometric characteristics of Northern
Harriers during autumn migration at Cape May Point, New Jersey. M.S. Thesis, Utah
State University, Logan, 90pp.
Schultz, C. and W.S. Clark. 2009. A Bander's Guide to Aging and Sexing Common
Eastern North American Raptors During Autumn Migration. Unpubl. Ms. Cape May
Raptor Banding Project in conjunction with Cape May Bird Observatory, New Jersey
Audubon Society. 20 pp.
Smith, J.P., S.W. Hoffman, and J.A. Gessaman. 1990. Regional size differences among
fall-migrant accipiters in North America. J. Field Ornithology 61:192-200.
Struve, S. and L. Goodrich. 1992. Distribution of band recoveries for sharp-shinned
hawks banded in the eastern Appalachian flyway. Unpubl. Rep. Hawk Mountain
Sanctuary, Kempton, PA, U.S.A.
65
Viverette, C., L. Goodrich, and M. Pokras. 1994. Levels of DDE in eastern flyway
populations of migrating Sharp-shinned Hawks and the question of recent declines in
numbers sighted. HMANA Hawk Migration Stud. 20(1):5-7.
Viverette, C.B., S. Struve, L.J. Goodrich, and K.L. Bildstein. 1996. Decreases in
migrating Sharp-shinned Hawks at traditional raptor-migration watchsites in eastern
North America. Auk 113: 32-40.
Wood, P.B., C. Viverette, L.J. Goodrich, M. Pokras and C. Tibbott. 1996. Environmental
contaminant levels in Sharp-shinned Hawks from the eastern United States. J. Raptor
Research 30: 136-144.
66