Harabin - York College of Pennsylvania

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Transcript Harabin - York College of Pennsylvania

A study of the Red-Bellied Turtle Population,
Pseudemys rubriventris, at Codorus State Park
Rick Harabin
Department of Biological Sciences, York College of Pennsylvania
Three trap site locations were picked near already
placed basking platforms.
The traps were designed to minimized stress and
danger placed on the captured turtles but to
capitalize their natural behavior of basking.
Each trap was checked for captives daily, for a
time period spanning 7-15 days per month.
The captured turtles’ measurements (mass,
carapace height, length and width) and # of
parasites were recorded, and their carapace was
marked for future identification (Ernst 1974).
Population Estimation & 95% Confidence Intervals
(Schnabel Method)
LITERATURE CITED
Red-bellied
Painted
Red-eared slider
Yellow-belly slider
Bernstein, N.P., Rightsmeier, R.J. and Black, R.W. 2007. Home Range and
Philopatry in the Ornate Box Turtle, Terrapene ornata ornata, In Iowa. The American Midland Naturalist. 157:162-174.
Ernst, C.H., Lovich, J.E. and Barbour, R.W. 1994. Turtles of the United States and
Canada. Smithsonian Institution Press, Washington, D.C.
Polo-Cavia, N., Lopez, P. and Martin, J. 2008. Interspecific Differences in
Responses to Predation Risk May Confer Competitive Advantages to Invasive Freshwater Turtle Species. Ethology 114:115-123.
Swarth, C.W. 1999. Natural History and Reproductive Biology of the Red-Bellied
Turtle (Pseudemys rubriventris). P73-83 In: Swarth, C.W., Roosenburg,
W.M. and Kiviat, E. (eds.). Conservation and Ecology of Turtles of the Mid-Atlantic Region: A Symposium. Bibliomania! Publishing Co., Salt
Lake City, Ut.
Urban, C. 2006. Common Wealth of Pennsylvania, Pennsylvania Invasive Species
Council Aquatic Invasive Species Management Plan. Available From
http://www.agriculture.state.pa.us/agriculture/lib/agriculture/gisfiles/PA_AISMP.pdf. Accessed 09 September 09.
Tran, S.L., Moorhead, D.L. and McKenna, K.C. 2007Habitat Selection
by Native Turtles in a Lake Erie Wetland, USA. The American Midland Naturalist. 158:16-28.
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Special Thanks,
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Dr. Jessica Nolan Assistant Professor
Biology York College of PA
Country Club Road
York, PA 17405
(717)815-6449
[email protected]
Time (Month)
Andy St. John-Park Manager Bureau of State Parks
Figure 1. The mean (+/- SEM) # of turtles/per day that were captured over a period
of 7-15 days per month. The mean with a * shows an significant difference (ANOVA test)
between # painted captured to all other species with a P values  0.01.
Resource Management Section
8th. Fl. Rachel Carson State Office Building
400 Market Street - P.O. Box 8551
Harrisburg, PA 17105-8551
direct line - (717) 772-0242
[email protected]
Sally Ray Zoologist Pennsylvania Natural Heritage Program
Red-Bellied
40
Painted
Red-Eared Slider
30
Yellow-Bellied Slider
20
10
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Ct = total number of individuals captured in sample t
Rt = number of individuals already marked in sample t
Mt = total number of individuals marked in population at sample t
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To help determine placement of multiple protected
reproductive sites
How?
• To begin to estimate population sizes for the four
different turtles species (red-bellied, painted, redeared slider and yellow-bellied)
• To determine where the red-bellied turtles are and
how they move between sample areas within Lake
Marburg in order to help identify home range size and
potential nesting locations.
CONCLUSIONS
• My estimate of the red-bellied turtle population is a
very low estimate making my work crucial for further
and more elaborate work to protect the species
(Table1.)
• The red-bellied turtles’ mean masses (Data not
shown) were consistent with previous known masses
(Swarth 1999, Ernst 1985 and Ernst et al. 1994)
• The red-eared slider’s population estimation could
not be determined with no recaptures but this could
be due to their excessively large population (Krebs
1999)
• The greater number of painted turtles captured in
July’s (Figure 1.), may be due to their higher tolerance
of warmer water (Ernst 1994 and Polo-Cavia et al.
2008)
• The red-bellied turtle exhibits a possible nesting and
feeding area shown by the recapture at a different
location (Table 2.)
• There were lots of turtles located at Chapel Cove,
making this a candidate for possible nesting locations
at nearby fields (Figure 4.)
C
OBJECTIVES
RESULTS
# Of Turtles Captured
To better understand the population size and habitat
use of red-bellied turtles, I conducted a markrecapture study at Lake Marburg in Codorus State
Park, PA.
•The red-bellied turtle is located in the coastal plain of
the mid-Atlantic region (Ernst et al. 1994)
•The red-bellied turtle is a state (PA) threatened
species due to habitat degradation and pollution
(Swarth 1999)
• Habitat diversity is crucial and consists of deep and
shallow foraging areas, numerous basking sites and
meadows or fields for reproduction (Swarth 1999)
• Red-bellied turtle may be outcompeted by other
native and invasive turtle species, in particular the redeared slider (Trachemys scripta) (Polo-Cavia et al.
2008, Urban 2006 and Tran et al. 2007)
• Habitat use may be partitioned seasonally, annually,
or by the sexes etc.; The understanding of these
different patterns, along with philopatry and home
ranges are all important to the management and
design of conservation techniques (Berstein et al.
2006 and Tran et al. 2007)
METHODS
# of Turtles
INTRODUCTION
Captured Location
Figure 4. Four species of turtles captured on Lake Marburg
(Codurus State Park) at 3 different locations.
Western Pennsylvania Conservancy
208 Airport Drive Middletown, PA 17057
[email protected]
Home office: (717) 292-4881