Photography as a Means of Identification of Individual Eastern
Box Turtles, Terrapene carolina carolina
Donald E. Hoss1, Carolyn R. Hoss1 and Antoinette M. Gorgone2
1Citizen
Scientist, 118 Straits Haven Road, Beaufort, NC 28516. dhoss@ec.rr.com
2NMFS, SEFSC, NOAA Beaufort Lab, 101 Pivers Island Road, Beaufort, NC 28516. annie.gorgone@noaa.gov
Introduction
The ability to identify individuals over long time periods can be used for mark-recapture techniques providing information on movement, distribution and
population size. Although, the most common method of marking box turtles for identification has been to file notches in their marginal scutes, this method is
invasive with potential of damage to the individual turtle. Photographic techniques to identify individuals by their natural markings have been well established
for many species. The purpose of this study was to determine if the pattern on the carapace of the Eastern Box Turtle (Terrapene carolina carolina) can be
used to identify individuals over long periods of time.
Discussion
Methods
• Box turtles captured opportunistically over a 12-year
period on 3.4 ha mostly wooded site in eastern Carteret
County, North Carolina (Figure 1).
• Left side of each turtle was photographed.
• The plastron length was measured for all turtles.
• Two of the authors compared captured turtles to the
photographic catalog of all identified individuals.
• The third author confirmed turtles identified as
recaptures.
• Patterns on the shell were easily identified and varied
among individuals (Figure 2).
• Identifying marks were well-defined, with each of the 13
scutes displaying individual patterns, minimizing
chance of misidentification.
• Scars or deformities in several turtles allowed validation
of individual ID through shell markings (Figures 3-4).
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Study area
Figure 1. North Carolina
Results
Conclusion
• Forty turtles were captured and photographed (Table 1).
• Sizes ranged from 2.8 to 15.2 cm straight plastron length.
• Sixteen turtles were captured more than once both within year
and between years.
• Longest recapture interval was 9 years.
• Smallest turtle recaptured was 6.4 cm at time of original
capture.
• Turtles >7 cm or larger in plastron length showed no change in
shell patterns over time.
• Unique and stable shell patterns on eastern box turtles
≥7 cm allowed easy recognition of individuals over time
through comparison of photographs.
• Photography is inexpensive, reliable and less invasive
than commonly used marginal scutes notching, making
it a preferable approach.
Tc028
Tc028 the smallest turtle captured at 2.8 cm
plastron length illustrating the different pattern
in young individuals.
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
Figure 3. The shell pattern of Tc003
shown in June 2005 and six years later.
Arrows are pointing to underbite which
verifies the identification.
Sex
F
Unk
M
M
M
F
F
F
M
M
M
M
Unk
F
F
M
F
F
M
M
F
F
F
M
Unk
M
F
Unk
F
M
M
M
M?
M
F
M
M
F
F
F
2002
August 2011
Turtle #
Tc001
Tc002
Tc003
Tc004
Tc005
Tc006
Tc007
Tc008
Tc009
Tc010
Tc011
Tc012
Tc013
Tc014
Tc015
Tc016
Tc017
Tc018
Tc019
Tc020
Tc021
Tc022
Tc023
Tc024
Tc025
Tc026
Tc027
Tc028
Tc029
Tc030
Tc031
Tc032
Tc033
Tc034
Tc035
Tc036
Tc037
Tc038
Tc039
Tc040
2001
June 2005
2000
Table 1. Resight history.
3
3
1
1
0
0
0
2
3
4
1
0
0
1
1
2
2
4
1
0
0
1
0
3
0
0
2
0
2
1
1
1
1
0
0
1
0
0
0
0
1
0
0
0
0
0
0
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
2
0
0
1
3
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
0
0
1
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
2
1
1
1
1
1
0
0
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
0
0
2
1
1
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
3
0
0
1
1
1
1
1
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
1
2
1
1
Years
between Plastron
Total
first and Length at
Times
last
capture
Sighted capture
(cm)
8
4
12.7
1
0
Unk
9
8
12.0
10
9
14.6
9
8
13.9
2
0
13.9
2
0
11.4
7
2
11.4
1
0
15.2
3
4
13.9
1
0
15.2
1
0
12.7
1
0
6.3
1
0
12.7
3
1
12.7
1
0
11.5
4
4
12.7
1
0
8.2
1
0
13.3
2
4
12.7
1
0
9.0
1
died
11.4*
2
0
13.5
1
0
14.5
1
0
2.8
1
0
Unk
1
0
10
1
0
3.5
1
0
12
4
1
13.9
1
0
13.9
1
0
12.5
1
0
Unk
1
0
10.8
2
1
6.4
1
0
13.3
2
1
13.6
2
0
8.8
1
0
8.9
1
0
8.3
August 2004
July 2011
Figure 4. The shell pattern of Tc004
shown in August 2004 and seven years
later. Arrows are pointing to damage to
shell which verifies the identification.
Figure 2. Five individual turtles illustrating the variation in carapace patterns.
Tc015
Tc010
Tc011
Tc017
Tc008