For over a century, conservation efforts have led to the establishment of hundreds of protected areas covering millions of hectares in the United States. These protected areas form the foundation for strategies to protect biological diversity and ecological processes upon which people and other species depend [1
]. Nevertheless, there is growing recognition that existing protected areas may be insufficient to sustain biodiversity as climate change and land development continue to impact natural ecosystems [2
]. In fact, referencing the Convention on Biological Diversity [3
], Aycrigg et al. (2016) [4
] recognized that “as significant as conservation areas are…they fall short of meeting recommended policy goals of each nation having established by 2020 an ecologically representative and well-connected system of protected areas.”
Recent calls have been made to add to the system of protected areas by establishing an ecologically connected network that is more inclusive of ecosystems and species currently under-represented in protected areas [3
]. In response to these calls, Belote et al. (2017) [5
] conducted a national assessment of wildland values and priorities for expanding the U.S. protected area system to include the most ecologically intact and wildest lands [6
], establish a national connected network [7
], and better represent ecosystem diversity [8
] and hotspots of range-limited species [9
]. Establishing a system of conservation reserves that is more resilient to climate change may require adding intact lands that connect existing protected areas and adding ecosystem and species representation to the existing system [1
At the same time, protecting what is left of the remaining wildlands (areas where human land use does not dominate ecological systems) has been recognized as a key conservation strategy [12
]. Watson et al. (2016) suggest that “protecting the world’s last wilderness areas is…our best prospect for ensuring that intact ecosystems and…evolutionary processes persist for the benefit of future generations.” Similarly, Ibisch et al. (2016) [14
] recently mapped Earth’s remaining roadless lands and described the global importance of these areas for additional conservation protection.
Marshall and Dobbins (1936) [15
] made similar calls for the protection of large tracts of wildlands after evaluating roadless areas over 80 years ago using paper maps to identify national conservation priorities. Today, national and global high resolution data on human impacts allow conservation scientists to better evaluate human land use changes [16
], identify roadless and wildland areas [12
], and map biodiversity [9
]. These datasets provide important opportunities for assessing the global or national importance of regions or local areas in conservation planning [2
]. Without such evaluations, local assessments and management recommendations may fail to consider the full conservation value of lands [2
In this paper, we used data compiled by Belote et al. (2017) [4
] to evaluate the national wildland conservation significance of the “Mountain Treasures” of western North Carolina for their value in completing a national network of conservation reserves. Ranging in size from 80 to 11,810 hectares, the Mountain Treasures are 53 units of land in the Southern Appalachian Mountains first identified in 1992 by citizens via spatial analysis of roadless areas and field verification [19
]. The citizen inventory and identification of Mountain Treasures was originally conducted in conjunction with the development of a management plan by the United States Forest Service. This inventory has been updated and refined in anticipation of the Forest Plan revision for the Nantahala and Pisgah National Forests that began in 2014 (see Appendix A
for the list of Mountain Treasures).
The Nantahala and Pisgah National Forests are primarily managed for multiple uses by the U.S. Forest Service, which administers over 78 million hectares throughout the United States [20
]. National Forests are managed under federal direction through the National Forest Management Act, which requires that management plans be updated on a regular basis (every 10–15 years). During management plan revisions, the Forest Service evaluates candidates of land units to be recommended to the U.S. Congress for additional conservation protections, including formal wilderness designation. Here, we use national data to assess the relative value of the Mountain Treasures, which are candidates for elevated levels of conservation protection, compared to other similar units on all other Forest Service lands of the contiguous U.S.
We evaluated the relative importance of adding the Mountain Treasures to the national system of conservation reserves by assessing their: (1) ecological integrity, (2) importance for connecting existing protected areas, (3) whether the composition of their ecosystems are national priorities for expanding representation, and (4) their importance as habitats for range-restricted and unprotected hotspots of biodiversity. These qualities derive from conservation principles to maintain biological diversity under the increasing pressures of climate change and land development. Protecting intact lands (areas of high ecological integrity) that connect protected areas and diversify the ecological representation of conservation reserves are among the highest conservation priorities. Here, we quantified these qualities and compared the Mountain Treasures to other similar candidates for elevated levels of protection occurring on Forest Service lands (Figure 1
). In so doing, we demonstrate a relatively straightforward method for evaluating the national significance of local areas during regional land use and conservation planning.
The Mountain Treasures represent some of the most important lands in the U.S. to establish a protected areas system that is intact, connected, and representative of ecological diversity and hotspots of range-limited species. Our assessment is based on a number of widely accepted principles from conservation science that provide guidance on how to construct a system of protected areas to maintain biodiversity and ecological processes in the face of habitat fragmentation and climate change [3
]. A conservation reserve system that is ecologically intact, connected in a network of protected areas, and representative of ecosystem and species diversity may provide the greatest degree of adaptive capacity in the face of a global change [10
]. Unprotected lands that possess these qualities may be considered high priorities for adding to the existing system of conservation reserves [5
]. The Mountain Treasures are not currently designated as highly protected lands.
In their valuable new paper, Aycrigg et al. (2016) state their intent to “start the conversation” about completing a national protected area system that is more representative of ecosystem and species diversity. Our objective here is to use a recent national assessment of wildland conservation values to assess the significance of North Carolina’s Mountain Treasures in helping to achieve a resilient protected area system of the future. The Mountain Treasures are among the most valuable roadless areas in the country for the qualities they currently maintain. It may be critical to consider their national significance in land management and conservation decisions. Without such broad-scale analyses, local decisions and actions may fail to appreciate important national [5
] or global [2
] conservation priorities.
The Mountain Treasures are less intact and wild compared to all roadless areas, many of which are in the western U.S. (Figure 2
A). This is not surprising given the higher density of human population, roads, and other disturbances experienced by ecosystems of the eastern U.S. Interestingly, at a global scale, biologically-rich areas tend to experience more intensive human modification [17
]. Thus, patterns of biodiversity and human modification of the Southern Appalachians represent an example of this global phenomenon [32
]. It is worth noting, however, that the Mountain Treasures represent some of the most intact and wildest places in the Southeastern U.S.
Despite the overall higher degree of human modification and lower degree of ecological integrity of the Mountain Treasures, on average their importance for establishing and maintaining a nationwide and regional connected network of protected areas is nearly identical to all other roadless areas in the U.S. [7
]. Many of the Mountain Treasures lie between existing protected areas and therefore represent important priorities for maintaining connections between existing conservation reserves including the Great Smoky Mountains National Park and wilderness areas in the Nantahala and Pisgah National Forests (Figure 4
). Creating a connected network of protected areas is among the highest recommended adaptation strategies to maintain biodiversity under a changing climate [7
The Mountain Treasures are also equally important compared to the other roadless areas with respect to expanding the representation of ecosystem diversity in protected areas (Figure 2
C). These roadless areas may be considered as reasonable candidates for future wilderness designation [25
], and protecting roadless areas composed of ecosystems poorly represented in wilderness and other highly protected areas should be considered high priorities for additional protections [24
]. Designating lands composed of poorly represented ecosystems will ensure that our protected areas system of the future includes all of nature’s diversity, and can be used as part of important climate adaptation planning [35
Compared to other roadless areas—the likely candidates for inclusion in an expanded conservation reserve system—the Mountain Treasures are some of the most biologically rich areas (Figure 2
D) and represent important conservation priorities [9
]. The richness of range-limited and endemic species in the Appalachians compared to other roadless lands is the result of paleo-ecological history [36
], the diverse climatic and edaphic gradients [37
], and the evolutionary history of the species in the region, e.g., [39
]. A number of species occur nowhere else on Earth or are geographically restricted, but remain without formal conservation protection [9
When combined, the four indices described above provide important insights into the national conservation significance of the Mountain Treasures. These roadless lands are among the nation’s most important if we are to construct a protected area system of the future that has the best chance of passing our natural heritage on to future generations. The Southern Appalachian Mountains have been identified as a critical region for historical [36
] and projected future [41
] climate change-driven species migrations. Minimizing or eliminated non-climate stressors to species and ecosystems through elevated levels of conservation protection may be regarded as a ‘no regrets’ climate adaptation conservation strategy [43
Our analysis is based on data representing the qualities of land important for constructing an ecologically representative and connected system of protected areas. Our goal was to provide a simple means of comparing local candidates for elevated levels of conservation protection to other candidates throughout the contiguous U.S. based on the recommendations of Aycrigg et al. (2016) [4
] and the assessment of Belote et al. (2017) [5
]. However, other ecosystem values or tools of conservation planning—not considered here—would enrich our evaluation. For instance, measuring ecosystem services [44
] and recreational or other economic values [45
] could provide additional insights into the relative value of the Mountain Treasures.
Other conservation optimization or prioritization tools may also provide important insights into the value and rank of the Mountain Treasures [27
]. Because Mountain Treasures are in the federal estate and are already publicly owned and managed, the cost of land will not need to be factored in, as in other conservation prioritizations [46
]. However, we recognize that our evaluation is but one resource used in a more complex approach to conservation planning [47
]. Our main goal was to provide insights into the potential national significance of the Mountain Treasures, because such insights might be easily overlooked by regional conservation planners.
In fact, other global or continental data could also be used to provide additional insights into conservation values of local areas, such as the Mountain Treasures. For instance, Pouzols et al.’s (2014) [2
] global evaluation of priorities for protected area expansion to meet international targets [3
] using over 24,000 terrestrial vertebrate species’ range maps reveals the Southern Appalachian Mountains to be in the top 20% of the highest priorities on Earth. In fact, several of the Mountain Treasures (Tellico Bald, Wesser Bald, Joyce Kilmer-Slickrock Extension #2-4, Dobson Knob, Linville Gorge Extension A, Sugar Knob, and Harper Creek) represent the top 10% of the highest global priorities for terrestrial protected area expansion on the planet (data available for download here: https://avaa.tdata.fi/web/cbig/gpan