Transcript Spatial Analysis of Endangered Amphibians Species and

Assessing North Carolina’s Current Protection of Amphibian Habitat
and Using Amphibian Umbrella Species to Highlight Areas of Concern
Jaime Neill and Maggie Caswell
Protected lands do not correlate
with amphibian habitats
Abstract
Works Cited:
Petranka, James W., Matthew E. Eldridge, and Katherine E. Haley. 1993.
Effects of Timber Harvesting on Southern Appalachian Salamanders.
Conservation Biology 7 (2), 363-370.
Wake, David B. 1991. Declining amphibian populations. Science 253,
860.
Willson J.D., and Dorcas M.E. 2003. Effects of habitat disturbance on
stream salamanders: Implications for buffer zones and watershed
management. Conservation Biology. 17(3): 763-771.
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0
0.01-3.00%
3.01-10.00% 10.01-18.00% 18.01-33.00% 33.01-74.00%
Percent Protected Area by County
Number of Common Amphibians Compared to Percent
Protected Area by County
Percent of Protected Area in
County
80.00
70.00
60.00
50.00
40.00
30.00
20.00
10.00
0.00
0
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Number of Common Amphibians Present in County
Calculating Percent Protected Area by County and Common Amphibian Distribution
North Carolina is a hot spot for amphibian species. 35 species of
salamanders alone are present in the Appalachian mountains of North
Carolina (Petranka et al. 364). Amphibians fill important niches in many
different ecosystems, often operating as both key predator and prey
(Wake).
Populations of amphibians in North Carolina as well as world wide
are rapidly declining. Human impacts are the major causes of this
decline in biodiversity. Habitat destruction, pollution, and species
displacement are the impacts that have had the most effect on amphibian
populations. Petranka, et al, found that clear-cutting forests resulted in a
75-80% loss in salamander populations that lived in the clear-cut area
(367). Trees are an integral part of the mountain ecosystem that many
amphibians make their home. Root systems stabilize the soil by retaining
its moisture content and by preventing erosion.
In their study on the effects of watershed management on
salamander populations, Willson and Dorcas found that small buffer
zones of protection around stream habitats offered insufficient protection
for salamander conservation. The implications of this study are that
larger areas need to be managed in order to conserve amphibian
biodiversity.
Protected lands in North Carolina need to be analyzed to determine
the inclusiveness of amphibian habitats and to determine which
unprotected lands should be protected to help prevent the decline of
North Carolina's amphibian populations. We believe that the current
expanse of protected lands in North Carolina provide insufficient
protection for amphibians because there is not an adequate cover of
protected lands and amphibian habitat.
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Using GIS to determine areas of concern
North Carolina is a hot spot for
amphibian biodiversity
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Number of Counties
North Carolina is a hot spot for amphibian species, but
population numbers of amphibians in North Carolina as well as
world wide have been rapidly declining. Protected lands in North
Carolina need to be analyzed to determine the inclusiveness of
amphibian habitats and to determine which unprotected lands
should be protected to help prevent the decline of North Carolina's
amphibian populations. We believe that the current expanse of
protected lands in North Carolina provide insufficient protection for
amphibians because there is not an adequate cover of protected
lands and amphibian habitat. By analyzing North Carolina's
protected lands and comparing the coverage to the habitats of
common amphibian species, the amount of protection to amphibian
species was determined. Because the protected areas did not
sufficiently cover the habitat ranges of the common amphibian
species, we tried to determine critical areas that would be the best
areas for amphibian conservation for all species. Seven
endangered amphibian species or amphibian species of concern
were used as umbrella species to highlight the most important
areas of concern. When comparing the distributions of the common
species and the umbrella species, different areas of concern were
highlighted. This indicates that while the conservation of the
umbrella species is the most imperative issue in the short term,
using the home ranges of these seven species is not sufficient for
protecting all amphibian species in the long term. Therefore, either
different or more species need to be analyzed in order to highlight
areas of concern that both protect the endangered species or
species of concern in the short term and all amphibian species in
the long term.
Percent of Protected Area by County
•Add North Carolina County Boundaries data layer (NCCB) and Amphibian Distribution data, which includes 10 common
amphibian species of North America (northern cricket frog, American toad, Cope’s gray treefrog, gray treefrog, eastern newt,
eastern red-backed salamander, northern two-lined salamander, mudpuppy, western lesser siren, and spring peeper)
•Clip Amphibian Distribution data to counties in North Carolina
•Join Amphibian Distribution data table to NCCB based on county names
•Using the field calculator, calculate total common species for each county in new field “amphib_tot”
•Add Lands Managed for Conservation and Open Space data layer (LMCOS)
•Create a Union data layer between NCCB and LMCOS
•In the Union layer, find the records that lie outside the conserved areas by using the select by attribute function
•Export data of selected records, named “Inverse_protected_area” (IPA)
•Calculate geometry of new field “inverse_area” of area in square kilometers in IPA data layer
•Calculate geometry of new field “total_area” of area in square kilometers in NCCB
•Join IPA attributes to the NCCB attributes table
•Using field calculator, subtract “inverse_area” from “total_area” in new field “pro_area” in NCCB
•Using the field calculator, divide “pro_area” by “total_area” and multiply by 100 in new field “percent” in NCCB
•Use graduated color symbology to create a chloropleth overlay of “percent”
•Use graduated symbols to create a proportional symbols overlay of “amphib_tot”
Mapping the percent of land protected in each
county and the number of amphibian species
present out of ten common amphibian species,
shows a correlation between the presence of
protected areas and the presence of
amphibians. The mountain, coastal and central
piedmont regions have the highest percentage
of protected lands, with the highest percentage
falling in the most western counties of North
Carolina. The largest occurrence of
amphibians is in the eastern mountain region
and the north eastern piedmont region. While
the counties with the highest number of
species in the mountain region do not correlate
with the highest percentage of protected area,
they all have at least 3% of land protected.
However, in the north eastern regions with high
numbers of amphibian species, the majority of
the counties have less than 3% of land
protected. This indicates that the current range
of protected lands is not very adequate for the
average amphibian species in the north
eastern piedmont region of North Carolina.
In order to determine areas to protect that would be beneficial for all amphibian species, seven endangered species or species of concern were
used as umbrella species. Areas where there are more than one umbrella species should be areas where there is more land protection. By
comparing the current protected areas with the habitat of the umbrella species, it is apparent that much of the critical habitat is not located within
protected areas. This is especially true in the south eastern piedmont region, where there is little land protection and large habitat regions for
endangered species or species of concern.
Critical areas must be protected
Spatial Analysis of Endangered Amphibians Species and Amphibian Species of Concern
•Add layer of NC county layer, protected area layer, and the layers for the seven different endangered species or species of
concern (Dwarf Salamander, Four-Toed Salamander, Gopher Frog, Mole Salamander, Neuse River Waterdog, Tiger
Salamander, and Wehrle’s Salamander)
•Add values for the amphibian data using raster calculator to find where more than one species overlap in habitat
Sources
•Boundaries – County [computer file]. North Carolina: NCCGIA, 2003.
•Current Distributions of Selected Amphibians in the United States [online database]. Reston, VA: National Atlas of the United
States, 2002.
•NCCGIA. Lands Managed for Conservation and Open Space [computer file]. North Carolina: NCCGIA, 2002.
•Biological Resources Division of the United States Geological Survey. Ambystoma tigrinum [computer file]. Raleigh, NC: NC
Gap Analysis Project, 2007.
•Biological Resources Division of the United States Geological Survey. Ambystoma talpoideum [computer file]. Raleigh, NC: NC
Gap Analysis Project, 2007.
•Biological Resources Division of the United States Geological Survey. Eurycea quadridigitata [computer file]. Raleigh, NC: NC
Gap Analysis Project, 2007.
•Biological Resources Division of the United States Geological Survey. Hemidactlium scutatum [computer file]. Raleigh, NC: NC
Gap Analysis Project, 2007.
•Biological Resources Division of the United States Geological Survey. Plethodon wehrlei [computer file]. Raleigh, NC: NC Gap
Analysis Project, 2007.
•Biological Resources Division of the United States Geological Survey. Necturus lewisi [computer file]. Raleigh, NC: NC Gap
Analysis Project, 2007.
•Biological Resources Division of the United States Geological Survey. Rana capito [computer file]. Raleigh, NC: NC Gap
Analysis Project, 2007.
•Using ten common amphibian species of North
Carolina shows that the current protected areas vary
in suitability depending on the region.
•In the mountains the protected areas are doing
a sufficient job but in the north eastern piedmont
there is little land protection and a high number
of amphibian species.
•This indicates that there should be more
protection in the north eastern piedmont region.
•Comparing the current protected areas with the
habitat distribution of the umbrella species indicates
that there are several suitable areas for future
protection.
•Many of these areas are in the south eastern
and north western piedmont regions where there
is little current land protection.
•The sandhill area shown in the figure is
important to preserve in the future since it is the
only region in North Carolina with four umbrella
species.
•The two different analyses indicate that different
areas need more protection.
•While endangered species and species of
concern need to be protected, the differences in
these two maps show that using these seven
umbrella species is not entirely adequate for
determining critical protection areas for all
amphibian species.
•For a more accurate representation of which areas should be protected to ensure protection of all North Carolina amphibian species further
analysis is needed.
•Either different or more umbrella species should be used so that their habitat range is a better representation of all North Carolina
amphibians.
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