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The Effects of Relocation on Home Ranges in Eastern Box Turtles
Megan C. Henriquez,1 Erin Baker,2 Michael Rubbo, Ph.D.,2 and J. Alan Clark, Ph.D., J.D.1
Background
Methods
Results • Hypothesis 1: Rejected. No difference between
resident and relocated home ranges
o Possibly due to small sample size; trend in
predicted direction
• Hypothesis 2: Supported. Home ranges for males and
females were similar
o Results are consistent with an earlier study of
relocated Eastern Box Turtles (Hester et al. 2008)
• Hypothesis 3: Rejected. Resident and relocated turtles
traveled similar distances
o Resident turtles traveled more in a smaller area,
perhaps because of familiarity with territory
o Relocated turtles traveled more in a wider area,
perhaps to find suitable habitat
Discussion
1Fordham University, Bronx, NY, 2Teatown Lake Reservation, Ossining, NY
• Eastern Box Turtles are 1 of 5 subspecies of U.S. Box
Turtles. This long-lived (100+ years), slowly
reproducing, terrestrial turtle has a hinged plastron that
allows it to completely close its shell against predators. (Dodd 2002)
• Habitat loss and fragmentation caused by urbanization
and collisions with vehicles negatively affect Box
Turtles, which are classified as vulnerable by IUCN. (van
Dijk 2011)
• Box Turtles are often brought to Teatown Lake
Reservation in Ossining, NY where they are
rehabilitated, released, and tracked as part of a multi-
year study.
• An earlier study of non-hibernating, relocated Eastern
Box Turtles in North Carolina found relocated turtles
had larger home ranges, traveled further, and had
higher mortality than resident turtles. (Hester et al. 2008)
• Turtles tracked for 6 weeks post
nesting using radio telemetry
• ArcGIS used to plot GPS points
• Calculated
oHome range using minimum convex
polygon method
o Total distance traveled
• Compared resident and relocated
turtles
• Compared males and females
.
Hypotheses:
1. Relocated turtles will have larger home ranges than
residents
2. Relocated turtles will travel further than residents
3. Both sexes will have similar home range sizes
Next Steps
• Track current turtles for rest of season and future years
• Continue to release turtles to increase sample size
• Collect and pool data from previous years
• Evaluate data on hibernacula location
Acknowledgements Special thanks to Suzanne Macey, Calder Summer
Undergraduate Research Program, and all the staff at
Teatown Lake Reservation n = 3 n = 3 n = 3
http://www.nps.gov/grsm/photosmultimedia/Wildlife.htm http://upload.wikimedia.org/wikipedia/en/4/45/EasternBoxTurtleMale.jpg
0
20000
40000
60000
80000
100000
Resident Male Resident Female
Relocated Male
Relocated Female
Ho
me
Ran
ge (
m2 )
Male and Female Home Range Comparison
0
400
800
1200
1600
Resident Relocated
Dis
tan
ce T
rave
led
(m)
Total Distance Traveled Comparison
n = 6 n = 6 0
20000
40000
60000
80000
Resident Relocated
Ho
me
Ra
ng
e (
m2)
Home Range Comparison
n = 6 n = 6
n = 3 n = 3 n = 3 n = 3
P = 0.19 P = 0.69
References Hester, J.M., Price, S.J., and Dorcas, M.E. 2008. Effects of relocation on
movements and home ranges of Eastern Box Turtles. Journal of Wildlife
Management 72:772–777.
van Dijk, P.P. 2011. Terrapene carolina. In: IUCN 2012. IUCN Red List of
Threatened Species. Version 2012.1. <www.iucnredlist.org>. Downloaded on
11 October 2012.
Dodd Jr., K.C. 2002. North American Box Turtles: A Natural History.
Norman: University of Oklahoma Press.
Home Range Comparison
Resident
Resident
Resident
Relocated