The Effects of Relocation on 100000 Male and Female Home ...€¦ · Box Turtles are often brought...

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