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Jaime Neill and Maggie Caswell. Protected lands do not correlate with amphibian habitats. Abstract. Assessing North Carolina’s Current Protection of Amphibian Habitat and Using Amphibian Umbrella Species to Highlight Areas of Concern.
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Jaime Neill and Maggie Caswell Protected lands do not correlate with amphibian habitats Abstract Assessing North Carolina’s Current Protection of Amphibian Habitat and Using Amphibian Umbrella Species to Highlight Areas of Concern 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. 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. Using GIS to determine areas of concern • Calculating Percent Protected Area by County and Common Amphibian Distribution • 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” • 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. North Carolina is a hot spot for amphibian biodiversity 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. 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 • 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. 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. • 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.