Identifying and Mitigating the Effects of Outdoor Rock Climbing on Surrounding Ecosystems in Colorado

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The Climb Towards Conservation: Identifying and Mitigating the Effects of Outdoor Rock Climbing on Surrounding Ecosystems in Colorado

By Chloe Sommer University of Colorado Boulder

A thesis submitted to the University of Colorado Boulder in partial fulfillment of the requirements to receive Honors designation in Environmental Studies May 2019

Thesis Advisors:

Dale Miller, Environmental Studies, Committee Chair Philip White, University Libraries Lon Abbott, Geological Sciences

Abstract

Since the 1960s, rock climbing has become an increasingly important player in America’s recreation landscape. Today, rock climbing is a growing contributor to the nation’s $800+ billion-dollar outdoor recreation industry, and indoor and outdoor climbing are more popular than ever. Historically, rock climbers and other outdoor recreationalists have claimed a correlation between recreation and conservation of public lands. Ample evidence suggests, however, that rock climbing still causes an array of negative impacts to ecosystems. This is the first known study to analyze potential impacts of recreational outdoor rock climbing on a large scale with GIS techniques, overlaying geographic data of outdoor climbing areas in Colorado with government landcover data for the state from 1970 and 2011 as well as public land ownership and designation data. Based on this analysis, around two-thirds of outdoor rock climbs in Colorado are located in evergreen forests or shrub / scrub land as defined by the US Geological Survey. Many historically forested areas frequented by climbers have experienced changes in landcover, converted into developed areas and shrub / scrub land since 1970. Additionally, 89% of climbing areas in Colorado are located on land with preexisting environmental protections: 68% federally regulated, 6% state regulated, and 15% city or county regulated. Using landcover and land use change data, I then propose specific management strategies to be implemented by small-scale local climbing organizations working collaboratively with larger governments to address environmental concerns identified through GIS analysis.

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Preface

For as long as I can remember, I have felt the inclination to climb. From ascending bookshelves in my childhood home as a toddler, to hiking up mountains hauling gear to climb steep rock faces as a young adult, the sport has always held a special place in my heart. When I moved to Boulder, Colorado and enrolled in university, my view of rock climbing shifted. As an Environmental Studies major, I was constantly looking at the world around me as an interconnected system of interactions between humans and their environment. Anthropogenic disturbance has arguably become the most dominating influence on Earth’s natural environments, and in studying the scope of human influence, I became passionate about conserving the delicately balanced biodiversity around me. Like most outdoor enthusiasts, I assigned a high value to nature as I continued to hike, climb, and explore new terrain. There was a certain thrill in finding sites virtually undisturbed by human influence, in stepping into unknown territory. But after a few years of studying human- environment interactions, I realized that my presence in wilderness reaped negative effects on the very landscapes I loved so much. Moreover, when I mentioned the concept of environmental management in regard to rock climbing, many of my peers responded skeptically and even hostilely. We discussed issues such as seasonal rock closures for raptor nesting, habitat restoration, and cultural events. This led me to discover that some climbers carry a sense of entitlement to access any outdoor locations they may desire, regardless of environmental or social effects. In my 12+ years climbing outdoors, I have observed a preconception among the community that rock climbing has little to no impact on its surrounding environment. This is the idea that I decided to investigate, and the idea that eventually developed into this thesis project. Rock climbing is not particularly well-studied in the world of academia, providing ample opportunity for future research. My hope is that this project becomes a drop in the bucket of scholarly research on outdoor rock climbing, and as the community continues to develop and grow, it does so in a self-aware, environmentally conscious way. Outdoor enthusiasts have gotten to play the role of environmentalists in the past, calling for land to be preserved as public parks rather than opened for resource extraction. But given the rapid growth of outdoor recreation and tourism over the past several decades, even non-extractive activities must be examined and controlled to ensure an ecologically stable future.

Acknowledgements

This project would not have been possible without the ideas and support of many important people in my life. Immense thanks to Ted Sommer: my dad, my first climbing partner, and the source of the idea behind this thesis; and to Jennifer Sommer, for always picking up the phone, and for learning to belay despite the fact that she does not climb. The encouragement of countless friends and family members kept me going throughout the entire research and writing process. Special thanks to Gwen and Tim Kittel, Dani Gurevitch, Miakoda Plude, Katie Mac Slabach, Liam Fisher, and my Environmental Studies honors thesis peers for all of their advice and support. I cannot thank you enough for listening to me talk through my project time and time again. I am indebted to my committee of advisors: Dale Miller, Philip White, and Lon Abbot, whose patience and expertise made the impossible possible. Dale, thank you for believing in my idea, for stepping up as Committee Chair, and for debating grammar with a clearly unqualified undergrad. Phil, you were indispensable to the completion of this project. Thank you for letting me clog your calendar with meetings, and for forgiving every missed deadline. To Nick Wilder of The Mountain Project, thank you for creating an invaluable resource for the climbing community, and thank you for trusting a random undergrad with your metadata. This project stands on the shoulders of the many climbers who have worked, generally unpaid, to balance climbing with conservation in the past. Your efforts inspire responsibility in us future generations.

“Most climbers are individuals who love freedom—they climb because it makes them feel free. We may expect then, that having others suggest how they ought to climb will rub wrong. There used to be so few climbers that it didn't matter where one drove a piton, there wasn't a worry about demolishing the rock. Now things are different. There are so many of us, and there will be more. A simple equation exists between freedom and numbers: the more people the less freedom. If we are to retain the beauties of the sport, the fine edge, the challenge, we must consider our style of climbing."

— Royal Robbins, Basic Rockcraft, 1977.

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Table of Contents

Abstract...... iii

Preface ...... v

Acknowledgements...... vi

Epigraph...... vii

Introduction...... 1

Background...... 5

Recreation Ecology and Rock Climbing...... 7

Vegetation...... 10

Soil...... 13

Wildlife...... 14

GIS: A Novel Approach to Recreation Ecology...... 15

Methods...... 18

Results...... 22

Discussion...... 33

Limitations of Study...... 38

Suggestions for Future Study...... 40

Application...... 42

Conclusion...... 48

References...... 50

Introduction

Scaling sheer cliff faces for fun has never been more socially accepted. Since the 1960s, rock climbing has become an increasingly important part of America’s recreation landscape.

Today, rock climbing is a growing contributor to the nation’s $800+ billion-dollar outdoor recreation industry, and indoor and outdoor climbing are more popular than ever (Outdoor

Industry Association 2017). Outdoor recreation retailers boast more political prowess than they have historically, as well; companies such as Patagonia, The North Face, and REI have funded research studies on the industry’s contribution to the American economy as they lobby for the protection of accessible public land. Historically, rock climbers and other outdoor recreationalists have claimed a correlation between recreation and conservation of public lands.

Ample evidence suggests, however, that rock climbing still causes an array of negative impacts to ecosystems, not unlike most outdoor activities. The outdoor industry can be harmful to the very landscapes it claims to protect. As rock climbing is one of the most rapidly growing outdoor sports in the nation, identifying and understanding its ecological consequences will be critical for mitigating them. In the age of outdoor recreationalists calling for conservation, we must question if and how to manage outdoor activities in order to align with conservationist values for a sustainable future.

Nearly all research identifying the environmental concerns associated with rock climbing suggest altered or increased management of outdoor recreation on publicly owned lands. Many further specified that local conditions and research had to be considered, and that varied ecosystems would require different, unique strategies for land management because different ecosystems require different protocols. A detailed understanding of these location-specific conditions is a necessity for moving toward sustainable policy that ensures conservation of

natural areas frequented by climbers. Currently, no large-scale academic studies have been conducted that attempt to identify potential “problem” areas frequented by rock climbers that may require management reform.

The state of Colorado, USA is home to some of the oldest and largest communities of outdoor rock climbers. Its popularity is largely due to Colorado’s complex geologic history and plentiful rock formations. Outdoor rock climbers travel all over the state, from the towering alpine granite of Rocky Mountain National Park, to the soft pink sandstone of Garden of the

Gods. Descendants of early European settlers pioneered into Colorado’s wilderness in the late

19th Century, exploring the Rocky Mountains for natural beauty and physical challenge (Achey,

Chelton, & Godfrey 2002). The city of Boulder became home base for the first-ever Rocky

Mountain Climbers Club founded in 1896, many decades before the sport gained significant recognition or popularity (Achey et al 2002). Through the years, travelers, immigrants, and academics made their way through Boulder and beyond, sharing and developing new climbing techniques. Technological advances during World War II brought army-supply nylon ropes to replace old, static hemp ropes, allowing for safer falls and propelling early climbers onto steeper, more challenging terrain (Achey et al 2002). By 1967, Boulder’s first outdoor climbing guidebook was published, providing even the novice with information on how to locate and safely climb local rocks (Achey et al 2002). These first steps were followed by decades of adventurers moving to and vacationing in Colorado, exploring new rocks and establishing more outdoor climbing areas. In 2019, Colorado remains one of the most important geographic and cultural destinations for rock climbers worldwide (Adventure Projects, Inc. 2019).

This study gains a broad overview of recreational rock climbing’s potential ecological impact in the state of Colorado by analyzing what types of ecological systems are visited by

climbers, determining any potential threats to those ecological systems, and assessing what legal protections are currently in place for those ecosystems. By understanding the abundance and nature of these potential impacts, specific and sustainable management strategies for climbing communities are then proposed for the future. As the sport grows, and more climbers with less experience head outside, customized novel management strategies are necessary to maintain the stability of the ecosystems climbers so often visit.

Background

Recreational rock climbing has been a pastime of bold adventurers since the mid-18th

Century. In the United States, organized communities of climbers existed as early as the 1910s, and the sport gained considerable attention and popularity in the 1980s as it was picked up by seasoned outdoorsmen and adrenaline-seeking, counter-culture youth alike (Attarian & Pyke

2000, Achey et al 2002, Taylor 2006). As outdoor climbing gained popularity, indoor climbing gyms popped up across the nation. More people than ever before had access to entry-level climbing, complete with paid instructors. The turn of the century saw a continuation of this trend; by 2000, an estimated 400,000 Americans identified as active climbers (Attarian & Pyke

2000). Self-made climbing legend Alex Honnold was featured on the cover of National

Geographic in 2011 and was the subject of Oscar-winning documentary “Free Solo” in 2018, further launching outdoor rock climbing into the public eye. In 2017, over 6 million Americans reported that they rock climbed at least once, indoors or outdoors, each year according to the

Outdoor Industry Association (OIA 2017).

Climbing has evolved with the times, representing more than just an adrenaline-inducing pastime. Rock climbing, like most other outdoor recreation industries in the United States, has progressively contributed to the national economy each year. In 2017, outdoor recreation of all kinds directly resulted in $887 billion in consumer spending, supporting 7.6 million American jobs (OIA 2017). Furthermore, this sector of the American economy contributes over $65 billion in federal tax revenue and more than $59 billion in local and state tax revenue annually (OIA

2017). Population modeling and United States Forest Service statistics project a continued increase in the number of outdoor activity participants through 2060; the entire industry is expected to maintain its trend of growth (Cordell 2012). Outdoor recreation retailers and industry

professionals have been gathering these statistics in recent years to build a voice in Washington, leveraging their collective political power into lobbying for protection and preservation of public lands (Outdoor Industry Association 2017, Access Fund 2018). This draw toward outdoor recreation is not an exclusively American trend, either; globally, nature-based tourism has been rising in popularity over the past decade, and outdoor recreation is becoming an increasingly large sector of such tourism (Balmford et. al 2009).

Historically, rock climbers and other outdoor enthusiasts have associated their outdoor recreation with conservation of public lands. After all, recreation retailers like The North Face,

Patagonia, and REI lobby to preserve national monument land designations so their customers may have publicly accessible rivers to ride on their kayaks, campsites to pitch their tents, and rocks to climb with their specialized harnesses, shoes, and helmets. Support for public lands, on a surface level, appears to be supporting environmentalist, conservation-oriented values

(Balmford et. al 2009, Reed & Merenlender 2008, Schild 2016). One study even correlates frequency of outdoor recreation with higher likelihood of contributing private land to conservation efforts (Farmer et. al 2016). Opening government-owned land to unbridled recreation, however, can negatively affect natural ecosystems. The effects of outdoor recreation on the environment pale in comparison to subsurface fossil fuel extraction or mountaintop removal for mining precious metals, but many of its activities result in ecological consequences.

Nonetheless, rock climbing may not display such obvious ecological effects as “consumptive” recreation, like fishing and hunting, but is still grouped among “nonconsumptive” activities that result in harmful impacts despite their non-extractive nature (Reed & Merenlender 2008). These impacts are of particular importance because nearly 60% of American climbing areas are located on federally managed public lands (Access Fund 2018). As the rock climbing community is a

significant and rising player in the world of outdoor recreation, it must establish sustainable environmental practices with well-designed management to garner public and political support.

Understanding and managing environmental impacts of rock climbing will be critical to accomplishing these goals—especially for an industry looking to leverage more political power.

Recreation Ecology and Rock Climbing

Rock climbing has been integrated into American culture for over half a century, but scholarly literature on rock climbing’s ecological effects did not pick up steam until the late

1990s. This is likely because it was a process of several decades for scientists to begin studying how outdoor recreation of any kind impacts the environment, let alone to hone in on rock climbing specifically. Research related to the ecological effect of rock climbing is a modern-day subsection of recreation ecology, defined as “the study of the environmental consequences or outdoor recreation/nature-based tourism activities and their effective management” (Monz,

Pickering, & Hadwen 2013). This field of research predates its own terminology; decades before the term “recreation ecology” was commonplace, conservation biologist Emilio Meinecke surveyed the impacts of tourism on vegetation in California redwood parks. He discovered that human disturbance on and off-trail was responsible for trampling young plants, exposing and damaging the roots of well-established plants, and threatening the survival of native vegetation

(Meinecke 1929). These anthropogenic disturbances deeply concerned Meinecke; he even asserted that “the main objective of the parks is likely to fail” without better management of sensitive ecosystems (Meinecke 1929).

Meinecke paved the way for later recreation ecologists. By the 1960s, biologist J. Alan

Wagar defined the problem of recreation-related disturbance in earnest. He suggested the

concept of “carrying capacity” be applied to wilderness areas in order to limit recreation-related disturbance to a non-critical level. Based off of observed degradation, he argued that the quality of recreation would decrease if the quality of environment decreased, inciting the need for conservation measures in land management (Wagar 1964). Wagar’s work inspired peers, and recreation ecology research increased in abundance around the 1970s, paralleling the growing traction of the American environmental movement (Pickering et. al 2009).

Recreation ecologists began comparing the relative ecological impacts of different recreational activities by the beginning of the 21st Century. Pickering et. al (2009) observed trail damage, soil erosion, and vegetation degradation of three different activities in Australia and the

United States: hiking, mountain biking, and horseback riding. They discovered that the different activities reaped different types and severity of environmental impacts, concluding that horseback riding displayed the greatest damage to ecosystems (Pickering et. al 2009). These activities are easily comparable as they share the same trails and site of impact. This convenience of study could be one reason why few to no studies exist comparing the relative impacts of rock climbing to other outdoor sports.

Collectively, recreation ecologists have established a theoretical model graphing frequency of use and severity of impact of natural resources. Most recreation ecologists agree that, starting with no use or impact, the curve steeply increases until it reaches an “inflection point” where the curve hits an asymptote, and any additional use only minimally increases environmental impact at that point (see Figure 1a) (Wagar 1964, Monz, Pickering, & Hadwen

2013). This “inflection point” theory has convinced land managers that after a certain point of disturbance, a site will not significantly change regardless of increases in use. The idea has spurred decades of “confinement strategy” management, the near-sacrificial technique of

limiting human recreation to specific, confined areas while saving greater portions of land from disturbance (Monz et al 2013). Literature shows, however, that even contained disturbance can result in significant ecological impacts (Reed & Merenlender 2008).

Monz et. al also describe an alternative relationship between frequency of use and severity of impact on an environmental resource. Their second model shows that environmental impact increases slowly and minimally with increased recreational use until it reaches a “primary threshold,” at which point the environmental impact dramatically increases with subsequent use, then eventually levels off in a similar asymptote to that of the curvilinear model (See Figure 1b)

(Monz et. al 2013). Given this alternative model, the authors recommend allowing more regions of wilderness be made available for low-frequency recreational use, as long as that use does not surpass the primary threshold. This management strategy could be the “golden ticket” for adventurous climbers seeking remote, less popular destinations for outdoor climbing.

Figure 1: Ecological impact as compared to increasing use of natural resources: two proposed models. Source: Monz, Pickering & Hadwen (2013). “Recent advances in recreation ecology and the implications of different relationships between recreation use and ecological impacts”

Climbing is a unique sport in that it encompasses a variety of activities, including hiking to the base of remote rocks, technical climbing itself, setting protection on rock faces, rappelling, and full-blown mountaineering. Due to its broad scope, literature on its impacts covers three main ecological elements: vegetation, soil, and wildlife. All three of these categories are relevant to some facet of climbing, and they all experience distinct ecological impacts with their own sets of implications.

Vegetation

Recreational outdoor rock climbing affects several different types of flora which grow in a variety of habitats affected by climbers. The majority of climbing-related literature on vegetation ecology studies cliff-face plant communities. Cliff-face flora are microbiomes that are nearly always pristine prior to rock climbing disturbances because of their remote nature (Vogler

& Reisch 2011). Different outdoor recreation activities exhibit unique ecological impacts, and rock climbing is the only sport which significantly affects ecological factors of cliff-face flora

(Attarian & Pyke 2000, Lorite et al 2017).

Several research studies have used similar methods: selecting several climbed cliff-faces and several pristine, unclimbed cliff-faces in comparable or nearby environments, and analyzing the ecological composition of the cliff-face flora of each. Across the board, climbing was found to negatively affect abundance, percent cover, organism size, and species richness of cliff-face plants with significant shifts in species composition as well (Lorite et. al 2017, Vogler & Reisch

2011, McMillan & Larson 2002, Attarian & Pyke 2000). Clark & Hessl (2015) conducted an even more detailed study comparing climbed to unclimbed cliff faces. Their results indicated that there was slightly lower abundance of vascular plants and lichens on climbed faces as compared

to unclimbed, but abundance of bryophytes remained unchanged. Cliff angle was reported to be the strongest indicator of species richness and abundance across all taxonomic groups, with more influence than disturbance from climbing (Clark & Hessl 2015). Lorite et. al (2017) went beyond the binary of comparing climbed and unclimbed faces, designing tiered scale from low to high climbing frequency. Their data supported that increasing severity of cliff flora disturbance was correlated with increasing frequency of use from climbers (Lorite et. al 2017). Finally, Vogler &

Reisch (2011) further examined disturbed cliff faces, noting that lichen and vascular plants were more abundant closer to the ground on climbed cliffs. The authors suggest that climbers may accidentally displace plants by knocking them downward, which could contribute to this spatial pattern (Vogler & Reisch 2011).

Cliff faces are not the only vegetated surfaces impacted by rock climbing. Anthropogenic trampling of ground vegetation and soil degradation are some of the most commonly studied topics in the field of recreation ecology (Monz et. al 2013). Vascular plant communities that inhabit cliff bases decrease in species abundance, density, and percent cover with increased frequency of rock climbing in a given area (McMillan & Larson 2002, Carr 2007, Rusterhok,

Verhoustracten, & Barr 2011). Carr’s 2007 study developed a unique procedure to determine ecological impact of climbing on vegetation in two popular climbing areas of Kentucky, even distinguishing between styles of climbing (sport, with permanent metal bolts in cliff walls; and traditional, with removable gear inserted for protection). Carr found that the negative impact of climbing on vegetation was three times more severe at sport climbing sites as compared to traditional climbing sites (Carr 2007). Both McMillan & Larson (2002) and Rusterhok et al

(2011) expressed concern for endangered, rare, or sensitive vegetation inhabiting frequently

climbed areas. Both articles recommended a ban on establishing any new routes in their given study areas in order to maintain pristine cliff habitat for remaining, living vegetation.

Hiking trails that lead to outdoor climbing routes pose even more threats to native vegetation. The patterns that Meinecke (1929) and Wagar (1964) observed decades ago are still prevalent today. Recreation-related anthropogenic disturbances to vegetation surrounding trails still includes reduced height and abundance of flora (Pickering et. al 2009, Cole 2004). Cole

(2004) observed that plant stem length and leaf area also decreased with proximity to frequently recreated areas, resulting in a subsequent loss of photosynthetic potential, which made plants less competitive in their environments. Reproductive cycles of many vascular plants displayed unusual patterns in areas closer to hiking trails as well (Cole 2004).

Presence of trails also causes an increased risk of foreign pathogens and seeds of non- native species (Cushman & Meentemeyer 2008, Davidson et. al 2005, Mount & Pickering 2009).

Hiking boots, socks, and shoelaces have all been identified as active vectors for seed dispersal, with associated risk of increased weeds and non-native plant abundance (Mount & Pickering

2009). In Northern California, where forests managers are scrambling to limit the spread of pathogenic Phytophthora ramorum (Sudden Oak Death), both Cushman & Meentemeyer (2008) and Davidson et. al (2005) found that the disease was more abundant in areas frequented by outdoor recreationalists. Trails easily become thoroughfares for dangerous pathogens with humans as vectors. Trail establishment increases likelihood of non-native species invasions and disease outbreaks by creating areas of exposed soil, an easy target for non-native pathogens, as well as providing mobile vectors for those pathogens. Rainy weather increases amount of soil stuck to boot soles, thus increasing occurrences of anthropogenic pathogen distribution

(Davidson et. al 2005). Disturbances resulting in prolonged effects, such as the spread of

contagious pathogens, are known as self-propagating impacts, and can have more severe consequences than other types of single-use disturbances (Pickering & Hill 2007).

It should be noted that, although trail impact studies are not sport-specific, rock climbers everywhere use trails to access outdoor climbing areas (Access Fund 2018). Past research on the ecological impacts of rock climbing has failed to recognize the significant role of hiking trails related to climbing areas, quick to divide different recreational activities into separate categories.

Yet, many outdoor recreationalists (including climbers) self-identify as enthusiasts of more than one activity, frequently combining several outdoor activities in single outings (Outdoor

Foundation 2018).

Soil

The impacts of rock climbing on soil are significantly less complex, or at least less researched, than its impacts on vegetation. In 1929, Meinecke detailed changes in soil due to frequency of hiking tourism in the California Redwoods. He noted that soil on trails experienced increased light exposure as well as greater variability of temperature and moisture (Meinecke

1929). Most recent studies agree that recreational rock climbing and hiking compacted soil and decreased its water storage capacity, leading to increased occurrences of runoff and erosion in disturbed areas (Attarian & Pyke 2000, Cole 2004, Pickering et. al 2009). Pickering et. al (2009) also noted increased exposure of rocks and bedrock in soil affected by hiking. Lastly, Rusterhok et. al (2011) sampled and compared soil from climbed and unclimbed sites. They discovered that climbing tourism decreased the density and altered the species composition of soil seed banks among Mediterranean cliff communities (Rusterhok et. al 2011).

Wildlife

Unfortunately for outdoor recreationalists, the impacts of ecotourism on wildlife are considered some of the most concerning effects of nature tourism (Wilkinson 2015). In the age of what some label the “Sixth Mass Extinction” (Briggs 2017), a global pattern of decrease in biodiversity has occurred for the past 20+ years (Buchart et. al 2010). Mammals, birds, and amphibians have displayed particularly concerning decline (Buchart et. al 2010). Climate change, recent increase in zoonotic diseases, nutrient pollution, and anthropogenic land use changes are among the factors threatening species worldwide (Buchart et. al 2010). Endangered species are threatened by numerous anthropogenic and environmental factors, motivating wilderness managers to prioritize their survival. Rock climbing and hiking alike have been found to cause declines in density of large predatory mammals (Reed & Merenlender 2008, Attarian &

Pyke 2000). A study in Northern California found similar results; even in regions with exclusively “benign” activities like hiking and birdwatching, researchers found that large mammals were only one fifth as abundant in areas with recreational trails than undisturbed areas.

Indeed, the real issue for some threatened species is not extinction, but rather “population decline to the point where many species only exist as remnants of their former abundance,” according to

Briggs (2017). This is of particular concern, as decline in large carnivores is long-observed to result in such consequences as trophic cascades and mesopredator release, further upsetting the balance of ecosystems (Crooks & Soulé 1999). Recreational rock climbing and hiking, though seemingly harmless activities, are both evidenced to displace and even occasionally extirpate sensitive native mammal and bird populations (Wilkinson 2015).

Bird populations in particular are already evidenced to benefit from management of outdoor recreation (Attarian & Pyke 2000). Although one study correlates outdoor recreation

with the displacement of threatened birds from their native habitat (Klein, Humphrey, & Percival

1995), management of outdoor activities has improved in recent years to better suit avian species. Rock climbing, an activity that generally occurs on cliff faces, poses specific threats to cliff-nesting raptor communities including Peregrine Falcons and Bald Eagles (Attarian & Pyke

2000). Climbers have identified and amended these threats; there are several success stories of ecological management to facilitate raptor nesting including Boulder County’s local program of seasonal climbing closures in Colorado (Attarian & Pyke). The impact of outdoor recreation on avian communities, however, may be highly variable based on local conditions and species composition (Klein, Humphrey, & Percival 1995).

GIS: A Novel Approach to Recreation Ecology

Recreation ecology has seen new strategies and significantly larger-scale studies in recent years thanks to the emergence of Geographic Information System (GIS) technology. Since its invention, GIS has become an increasingly popular tool to assist in identifying, modeling, and predicting human impacts on natural ecosystems (Davis & Quinn 2004, Merem et. al 2011).

Broad-scale ecosystem studies are particularly valuable in the field of conservation biology, which has historically focused on species, subspecies, and population ecology (Franklin 1993).

Large, ecosystem-scale studies are able to consider the many species that coexist within interconnected habitats—terrestrial, aquatic, subterranean, tree canopy—and prioritize biodiversity at the ecosystem level (Franklin 1993, Lathrop & Bognar 1998).

Lathrop & Bognar utilized GIS in a 1998 study assessing recent land use change and its threat to the Sterling Forest on the border of New York and New Jersey. Their assessment

included land area change, gauged anthropogenic threats in the area, and was ultimately used to propose a conservation-development plan with the developer in the area.

Butt et al (2015) conducted a similar GIS analysis of land use change in the Simly

Watershed of Vietnam, using landcover data over time to determine that historic areas of vegetation and water had been developed into settlements and agricultural land. GIS was also used to assess land use and suggest future management for a study in Poland, which used 5m spatial resolution to compare vegetation and soil erosion to determine best locations for potential trails (Tomczyk 2010). Merem et al (2011) used similar methodology for a GIS study of human health and land use change in southern Texas watersheds. The study argues that geospatial analyses of anthropogenic impact can be valuable for management suggestions (Merem et al

2011).

Outdoor rock climbing is a large-scale occurrence, and as such could benefit from large- scale GIS analysis. Colorado alone is home to over 25,000 documented outdoor climbing routes in regions all over the state, with particular abundance in the Rocky Mountains (Adventure

Projects Inc., 2018). This study examines the state of Colorado due to its abundance of rock climbers, array of diverse ecosystems, and historic significance to the sport. Colorado is also representative of the greater demographic changes in the “New West” (Hansen et. al 2002).

Colorado, Wyoming, Utah, and Colorado have all seen an increase in population, especially around their communities near natural amenities (e.g. Boulder’s flatirons). This influx of new residents can be accredited to accessibility of outdoor recreation and has consequently increased stresses on native ecosystems (Hansen et. al 2002) Biodiversity, species abundance, and ecosystem processes have all suffered in newly populated regions (Hansen et. al 2002).

Although past studies have identified acute effects of rock climbing on specific, individual locations, few to no large-scale studies on the subject exist. This study utilizes large- scale GIS analysis to determine outdoor rock climbing’s potential ecological impacts, and how public land designations may influence such impacts. It analyzes locations of climbing areas in

Colorado to determine what type of terrestrial landcover and corresponding ecosystems are most visited by recreational climbers and determines how many climbing areas are located in protected land areas on local, state, and federal levels. Additionally, this data should identify any regions or species in the state potentially threatened by outdoor recreational rock climbing. By identifying which ecosystems and species display the most potential for suffering negative impacts of rock climbing, this study suggests customized management strategies for some of the state’s most-visited climbing hotspots.

Methods

A GIS database was created combining point data of outdoor climbing locations in

Colorado with landcover and land ownership raster data for the state. This study utilizes landcover data from both 1970 and 2011 to compare how Colorado’s climbing landscape has changed over 40 years, identify which climbing areas have undergone recent development, and determine if there are any climbing areas that present serious threats to native ecosystems. A land ownership / designation data layer is also implemented to understand how many climbing areas are located in public lands with preexisting protections, regulated by different governing bodies on local, state, federal, and nongovernmental levels. Geographic data for climbing locations in

Colorado was acquired by request from The Mountain Project, a crowd-sourced online map and guidebook for outdoor climbing areas worldwide. The Mountain Project provided metadata for

2,686 points which each represent one of the state’s outdoor climbing areas, including rock wall name and geographic coordinates. The Mountain Project defines a “climbing area” as distinct rock face, boulder, or mountain with at least one established climbing route.

Landcover data from the 1970s was sourced from the United States Geological Survey’s historical Land Use and Land Cover (LULC). This dataset was created using historic in situ government surveys from 1970, refined with population density data from 2000, and published in 2005. GIS computer applications were not invented until the 1960s and did not gain popularity in academia until the late 1970s, so digitalized historic data is sparse, with lower levels of accuracy than modern data (Clarke 1986). This 1970s dataset claims a resolution of 30m, but functionally only displays blocks of 100m resolution. Its landcover categories are somewhat broad and were defined based on land use and most dominant vegetation (or lack of) at the time of survey. Colorado’s climbing areas spanned 15 landcover types in 1970.

Modern landcover data was acquired from two different sources: 2011 National Land

Cover Data (NLCD) from the Multi-Resolution Land Characteristics Consortium, 2011

GAP/LANDFIRE National Terrestrial Ecosystems (NTE) data from the United States Geological

Survey, and 1970 USGS Land Use and Land Cover data. Two sources of landcover data from

2011 have been utilized because each dataset was created for a different purpose, and the two possess value though comparison to one another. The NLCD’s objective is to gather basic information on landcover and its change over time and defines each cell with one of just 16 landcover classes. NTE data focuses on precise classification of land in order to monitor and preserve biodiversity. For its complete United States data, NTE cells are classified as one among hundreds of specific ecosystem types. For the purposes of this study, climbing areas in Colorado totaled 49 different ecosystem types. Both the NLCD and NTE data have grid cell resolution of

30 m, meaning that all of Colorado’s territory was divided into 30m2 plots and assigned landcover values. The majority of landcover data for both 2011 sources was produced with satellite imagery (Homer et al 2015, USGS 2016). Finally, land ownership / designation data was acquired from the United States Geological Survey’s Gap Analysis Program. Their map outlining federal, state, local, and tribal land designation boundaries published in 2016 provides insight as to the legal owners of Colorado’s land as well as preexisting protections of that land.

All four landcover and ownership datasets were imported and overlaid with Mountain

Project climbing area data on QGIS 2.18 (See Figures 2, 3, 4 & 5). The QGIS Point Sampling

Tool plugin was used to extract LULC, NLCD, NTE, and land ownership designation values for each geographic point of Mountain Project data (outdoor climbing locations). The landcover values were added to the Mountain Project data’s attribute table, which was then exported to

Microsoft Excel for data analysis. At this point, landcover values for LULC, NLCD, and NTE

were numerically coded, and ultimately were converted back to the landcover classifications they signified via each respective dataset’s legend. For example, the numerical code “41” equates to

“Evergreen Forest” landcover designation in the 2011 NLCD dataset.

Figure 2: Mountain Project Climbing Location Points Overlaid on 1970s LULC map of Colorado Image exported from QGIS 2.18

Figure 3: Mountain Project Climbing Location Points Overlaid on 2011 NLCD map of Colorado Image exported from QGIS 2.18

Figure 4: Mountain Project Climbing Location Points Overlaid on 2011 NTE map of Colorado Image exported from QGIS 2.18

Figure 5: Mountain Project Climbing Location Points Overlaid on USDA Land Ownership / Designation Territories in Colorado Image exported from QGIS 2.18

Results

The GIS analysis produced a comprehensive ranking of how many climbing areas in

Colorado were located in each 1970s landcover type (classified by LULC), 2011 ecosystem type

(classified by NTE) and 2011 landcover type (classified by NLCD). In the 1970s, Colorado climbing areas were located in 15 different LULC types, with a select few landcover types accounting for the majority of climbing areas (see Figure 6). 2011 data indicates that Colorado climbing areas span throughout the state over 12 different NLCD landcover types and 49 different NTE ecological system types. NLCD landcover types, which have broader definitions and thus fewer categories than NTE classifications, classify much larger portions of Colorado’s outdoor climbs than any individual NTE ecological system type. The division of 2011 NLCD vegetation zones and NTE ecosystem types in Colorado are illustrated in Figures 7 & 8 below.

Figure 6: Percent of Colorado Climbing Areas per 1970s Land Use / Land Cover Type Note that resolution of 170s data is only 1/3 as high as both datasets from 2011. Sourced from the United States Department of the Interior via data.gov.

Figure 7: Percent of Colorado Climbing Areas per National Land Cover Data Vegetation Zone. NLCD vegetation zones are defined by the U.S. Geological Survey. Evergreen Forest (39% climbing areas), Shrub/Scrub (33%), and Developed, Open Space (8%) were the three most-visited landcover types for climbers.

Figure 8: Percent of Colorado Climbing Areas per National Terrestrial Ecosystem Type (2011) National Terrestrial Ecosystem Types are determined by the dominant vegetation composition in any given area. Descriptions of each individual ecosystem type are sourced from the United States Geological Survey in association with NatureServe.

According to LULC data (see Figure 6), in 1970 67% of Colorado climbing areas were located in Evergreen Forest Land, 10% in Shrub and Brush Rangeland, 9% in Mixed Rangeland,

3% in Mixed Forest Land, and 3% in Bare Ground (Tundra), and 3% in Bare Exposed Rock. The remaining 5% of climbs were located in a variety of landcover types accounting for 2% or less of all climbs. This data has lower accuracy than modern data due to its lower resolution and nonspecific categories, but is the best available landcover data for its time.

Under 2011 NLCD classifications (see Figure 7), 39% of Colorado climbs are located in

Evergreen Forest, 32% in Shrub/Scrub, 8% in Developed Open Space, 7% in Barren Land, 5% in

Developed Low Intensity land, and 4% in Grassland/Herbaceous territory. The remaining 5% of climbing areas are located in landcover areas that account for 2% or less of all climbs in the state. It is notable that together, Evergreen Forest and Shrub/Scrub land are home to over two thirds of all outdoor climbing areas in Colorado.

As previously mentioned, GAP/LANFIRE National Terrestrial Ecosystem data has more landcover categories with more specific definitions than the other two datasets. NTE’s specific ecosystem types provide details that NLCD’s broad categories do not. The most common 2011

NTE ecological systems rock climbers visit (see Figure 8) are Colorado Plateau Pinyon-Juniper

Woodland (15.6% climbing areas), Southern Rocky Mountain Ponderosa Pine Woodland

(15.3%), Rocky Mountain Lower Montane-Foothill Shrubland (9.1%), Developed, Open Space

(7.7%) and Colorado Plateau Pinyon-Juniper Shrubland (6.1%), Colorado Plateau Mixed

Bedrock Canyon and Tableland (4%), and Developed, Low Intensity land (4%). The other 37% of climbing areas are located in ecosystem types that account for 2% or less of all ecosystems in the state. The “Other” category includes 42 different ecosystem types. Within that list, seven different ecosystem types are home to more than 50 climbing areas: Southern Rocky Mountain

Mesic Montane Mixed Conifer Forest and Woodland, Rocky Mountain Gambel Oak-Mixed

Montane Shrubland, Southern Rocky Mountain Dry-Mesic Montane Mixed Conifer Forest and

Woodland, Inter-Mountain Basins Montane Sagebrush Steppe, Rocky Mountain-Sierran Alpine

Bedrock & Scree, Rocky Mountain Lodgepole Pine Forest, and Inter-Mountain Basins Big

Sagebrush Shrubland. Many of these ecosystems are found nearby large patches of Colorado

Plateau Pinyon-Juniper Woodland (15.6% areas) and Colorado Plateau Pinyon-Juniper

Shrubland (6.1%), so have a high potential for similar ecological concerns as the top 5 most common ecosystems. There are not many large areas of land with exclusively “fringe” ecosystems (containing <100 but >50 climbing areas in the state). The remaining 35 ecosystem types contain less than 50 known climbing areas throughout the state. While these climbing areas are likely ecologically significant to local ecosystems, this study seeks to gain a broad overview of Colorado’s potential ecological concerns determined based on total percentage of climbs in the state, and these ecosystems all account for <1% of the state’s total outdoor climbs.

In comparing 1970s LULC data (see Figure 6) with 2011 NLCD and NTE data (see

Figures 7 & 8), it is difficult to discuss differences between the graphs without reiterating that the datasets were not necessarily designed to be compared; LULC is much lower resolution and is defined by slightly different landcover categories as the other datasets used in this study.

However, 2011 NLCD data provides the closest resource with comparable landcover types (e.g.

1970 “Evergreen Forest Land” will be considered equivalent to 2011 “Evergreen Forest”). The

United States Geological Survey’s National Land Cover Database of 2011 was also developed from historic land cover and land use surveys including the 1970 data examined in this study; it is reasonable to compare the two, as they are closely related in methodology of data collection.

Figure 9 (below) shows how the amount of Colorado climbing areas located in four different comparable landcover types changed between 1970 and 2011.

Figure 9: Number of Colorado Climbing Areas per NLCD Landcover Type, 1970 vs. 2011. NLCD vegetation zones are defined by the U.S. Geological Survey. Landcover classes from 1970 and 2011 that share similar names and definitions are compared as the best possible representation of landcover data for each year.

The number of climbs located in Evergreen Forest land, as defined by the NLCD, have dramatically decreased from 1970 to 2011. This is likely because within that time, some of

Colorado’s historic evergreen forest land has been converted to Developed Land of varying stages, ranging from building development to open space development. The number of climbs located on Shrub / Scrub land has increased, indicating that historically different landcover types have become dominated by shrub / scrub since 1970. Finally, there have been slight increases in

Barren Land / Rock and Developed Land territory in 2011 as compared to 1970. These land cover and land use changes may be representational of how Colorado’s land has changed statewide across the past four decades. This study observes how outdoor rock climbing affects the land, but for these broad-scale changes, other factors including land privatization, development, and urban sprawl also likely contribute to land use and land cover change.

2011 landcover data is the most recent data available to determine the biggest ecological concerns for each landcover type heading into the future. This study utilizes 2011 statistics to draw conclusions about the condition of Colorado’s natural environments in 2019. Due to the large amount of ecosystem types that only account for small fractions of the state’s total climbing routes, the top five most common land types of each 2011 dataset have been ranked and described below (See Figures 10 & 11), as they are the most abundant and relevant in understanding potential large-scale impacts of recreational outdoor rock climbing.

Figure 10 (see page 29) lists the most prominent NLCD classifications for outdoor climbing areas in Colorado, as of 2011. For each classification, potential concerns are drawn based on common impacts of outdoor climbing as observed by past researchers, as discussed in the Background. Figure 8 presents the top 5 NTE ecosystem types for 2011 in a similar manner, but with the addition of specific at-risk species reported for each ecosystem rather than hypothetical concerns sourced from background knowledge. Lists of at-risk species for each

NTE ecosystem type were acquired through NatureServe Explorer’s Ecological System

Comprehensive Reports.

Historically and currently, most climbing areas in Colorado are located in Evergreen

Forest or Shrub / Scrub land, as classified by the NLCD. Overall, NTE landcover data suggests that Colorado climbers pose threat to the habitat of a select few birds (Pinyon Jay, Gunnison

Sage-Grouse, Greater Sage-Grouse) and low-lying shrubs (various Milkvetch species, Huber’s

Pepperwort). According to both NLCD and NTE data for 2011, developed land (including

Developed, Open Space and Developed, Low Intensity of NLCD and Developed, Open Space of

NTE) accounts for a greater amount of climbing areas than it did in the 1970s.

Percentage of NLCD CO Climbing Potential Rank Classification Areas Located Description of Landcover Type Concerns for Within NLCD Ecosystem (USGS 2016) Classification (USGS 2016) 1 Evergreen Forest 39% Areas dominated by trees generally Preexisting threats greater than 5 meters tall, and greater to evergreen than 20% of total vegetation cover. forests, especially More than 75% of the tree species bark beetles & maintain their leaves all year. Canopy wildfires1 is never without green foliage. 2 Shrub/Scrub 33% Areas dominated by shrubs; less than Potential 5 meters tall with shrub canopy biodiversity loss, typically greater than 20% of total loss of habitat for vegetation. This class includes true animals and plants shrubs, young trees in an early native to regions2 successional stage or trees stunted from environmental conditions. 3 Developed, Open 8% Areas with a mixture of some Balancing impact Space constructed materials, but mostly from climbing with vegetation in the form of lawn grasses. other nearby Impervious surfaces account for less anthropogenic than 20% of total cover. These areas impacts3 most commonly include large-lot single-family housing units, parks, golf courses, and vegetation planted in developed settings for recreation, erosion control, or aesthetic purposes. 4 Barren Land 7% Areas of bedrock, desert pavement, Exacerbated (Rock/Sand/Clay) scarps, talus, slides, volcanic material, erosion, increased glacial debris, sand dunes, strip mines, runoff, potential to gravel pits and other accumulations of decrease nearby earthen material. Generally, water quality4 vegetation accounts for less than 15% of total cover. 5 Developed, Low 5% Areas with a mixture of constructed Balancing impact Intensity materials and vegetation. Impervious from climbing with surfaces account for 20% to 49% other nearby percent of total cover. These areas anthropogenic most commonly include single-family impacts5 housing units. Figure 10 (above): Top 5 Most Common NLCD Landcover Types Frequented by Climbers ‘Descriptions of Landcover Type’ sourced from NLCD on the United States Geologic Survey website. Citations for ‘Potential Concerns for Ecosystem’ located in footnotes, with complete citations in Works Cited. Figure 11 (page 30): Top 5 Most Common NTE Ecological System Types Frequented by Climbers At-Risk Species Reported for Ecological System sourced from NatureServe’s online encyclopedia. Descriptions of ecological systems summarized from NatureServe Explorer’s Ecological System Comprehensive Reports. “At-Risk Species” are assessed and determined by independent researchers at NatureServe. Rarity, threats, and recent population trends are all considered to conclude if a species is at risk of decline or extirpation.

1 Kulakowski & Veblen 2007, Bentz et al 2010 2 Attarian & Pyke 2000, Cole 2004, Reed & Merenlender 2008, Pickering et al 2009 3 Buchart et al 2010 4 Attarian & Pyke 2000, Davidson et al 2006, Pickering et al 2009 5 Buchart et al 2010

Percentage of Ecological System Colorado Description of At-Risk Species Rank Classification Climbing Areas Ecological System Reported for Ecological Located Within System (USGS 2016) Ecological (NatureServe 2018) System (NatureServe 2018) 1 Colorado Plateau Pinyon- 15.6% Found in dry 1. Astragalus cronquistii Juniper Woodland mountains and (Cronquist's Milkvetch) foothills on warm, dry 2. Astragalus debequaeus land. Soils may vary in (DeBeque Milkvetch) texture from stony, 3. Gymnorhinus course sand to clay. cyanocephalus Tree canopy (Pinyon Jay) dominated by Pinus edulis and/or Juniperus osteosperma. 2 Southern Rocky Mountain 15.3% Found at lower None Ponderosa Pine Woodland treeline between grass/shrubland and coniferous forests. Typically inhabit warm, dry, exposed sites, most common on steep slopes to ridgetops. Generally coarse, rocky soil. Dominated by Pinus ponderosa. 3 Rocky Mountain Lower 9.1% Found in foothills, 1. Astragalus anisus Montane-Foothill canyon slopes and (Gunnison's Milkvetch) Shrubland lower mountains of the 2. Astragalus ripleyi Rocky Mountains. (Ripley's Milkvetch) Typically exposed, 3. Centrocercus minimus* rocky, and dry with (Gunnison Sage-Grouse) limited tree growth. 4. Centrocercus Cercocarpus urophasianus montanus and other (Greater Sage-Grouse) grasses and shrubs 5. Lepidium huberi dominate. (Huber's Pepperwort) Disturbances (e.g. fires) necessary to maintain ecosystem. 4 Developed, Open Space 7.7% N/A N/A 5 Colorado Plateau Pinyon- 6.1% Found on rocky 1. Gymnorhinus Juniper Shrubland mesatops and slopes of cyanocephalus Western Colorado. (Pinyon Jay) Typically dry, with shallow/rocky soils and stunted trees. Dominated by short Pinus edulis and/or Juniperus osteosperma and shrubs. * = Federally Threatened under the Endangered Species Act

Finally, analysis of Mountain Project data overlaid with land ownership / designation data revealed that 89% of all climbing areas in Colorado are located on land with preexisting legal protections (see Figure 12). Approximately 68% of climbs in Colorado are federally owned; this includes Bureau of Land Management land (32% climbing areas) or National Forest land (31% climbing areas), and National Park land (5% climbing areas). The State of Colorado oversees 11% of all climbing areas studied, with state parks accounting for 10% (including

Eldorado Canyon, Castlewood Canyon, Lory, and Staunton State Parks) and other state-owned areas constituting 1% of all areas (see “Other” in Figure 12). City park land accounts for nearly as many climbing areas as state-owned land, home to 10% of Colorado’s outdoor climbing areas.

The cities with legal ownership to Colorado’s climbing areas include the City of Boulder

(majority), City of Colorado Springs, City of Rifle, and City of Denver. County-owned land is also a significant regulator, home to 5% of the state’s climbing areas. 11% of climbing areas in the state have no known land designations / legal protections as determined by GIS analysis.

Details on protections for each land designation are described in Figure 13.

Figure 12: Percent of Colorado Climbing Areas per Legal Land Designation (2011) Land Designations are determined by governments in the United States on local, state, and federal levels. Land designation data sourced from the United States Department of Agriculture.

Figure 13 (below): Land Designations and Legal Protections of Colorado Outdoor Climbing Areas Legal Land Designations sourced from the United States Geological Survey’s 2016 report on land ownership and protections. Percentage of Colorado climbing areas determined through GIS analysis. Descriptions of Land Protections acquired from various sources, listed in footnotes. Figure continued on page 31.

Legal Land Percentage of CO Designation Climbing Areas Description of Land Protections Rank Located Within (USGS GAP 2016a) Land Designation 1 Bureau of Land 32% Land must accommodate “opportunities for Management commercial, recreational, and conservation activities.” Little regulation of climbing, land overseen by BLM field offices. Stricter regulation within Penitente Canyon, a BLM Special Recreation Management Area. Paid, registered guides must file for commercial permits.6 2 National Forest Land 31% Most climbing areas located within Arapaho and Roosevelt National Forests, or in Pike and San Isabel National Forests. Managed under “multiple use concept,” balancing resource extraction, grazing, and recreation. Generally no restrictions on outdoor climbing, except in specially designated areas (e.g. Wilderness Areas)7 3 None 11% No known legal protections 4 City Park 10% Varies based on city. City of Boulder, City of Colorado Springs, and City of Rifle contain the most city park climbing areas in the state. Include seasonal closures for wildlife nesting, registration and certification for commercial guides, restrictions on bolt placement and replacement8 5 National Park 5% National Parks “protect a variety of resources, including natural and historic features” and “strive to keep landscapes unimpaired for future generations while offering recreation opportunities.” Include Rocky Mountain, Black Canyon of the Gunnison, Rio Grande, and Colorado National Monument. Regulations vary depending on specific park. Generally, prohibit new route establishment, implement seasonal wildlife closures, & require permits for multi-day climbs. Collaborate with LCOs.9 6 County Land 5% Varies depending on county. Counties with the most outdoor climbing areas are: Jefferson County (includes Clear Creek Canyon

6 Bureau of Land Management. (2018, October 17). A landscape approach: How we manage. Retrieved from https://www.blm.gov/about/how-we-manage 7 U.S. Department of the Interior. (2018, December 18). America's public lands explained. Retrieved from https://www.doi.gov/blog/americas-public-lands-explained 8 Colorado Springs Department of Parks, Recreation, and Cultural Services. (2019, January 18). 2019 Rock Climbing Permit. Retrieved from https://coloradosprings.gov/parks/webform/2019-rock-climbing-permit 9 U.S. Department of the Interior. (2018, December 18). America's Public Lands Explained. Retrieved from https://www.doi.gov/blog/americas-public-lands-explained

and North Table Mountain), Eldorado County, Boulder County (includes Boulder Canyon), Larimer County (Horsetooth Reservoir), & Douglas County 7 State Park 5% Includes Eldorado Canyon, Castlewood Canyon, Lory, and Staunton. Permit required to place or remove any fixed climbing protection (bolts and pitons). Commercial climbing guides must be certified or employed by an accredited organization & obtain permits. Additional regulations vary depending on park.10 8 Other 1% Protections vary based on owner. Includes 8 areas owned by the State Land Bureau, 5 areas located in a State Wildlife Area (the Vail Deer Underpass), 1 area owned by the Commissioners of the Land Office on “School Land,” and 1 area owned by an NGO near Nederland, CO.

In addition to the land designations and protections described in Figure 13, it is notable that 6.1% of climbing areas in Colorado are located within federally designated Wilderness

Areas, which can overlap with other federal land designations including BLM land, National

Forests, National Wildlife Refuges, and National Parks (Colorado’s Wild Areas 2019).

Wilderness Areas are unique from other public land designations, because regulations strive for

“preservation of their wilderness character” (Wilderness Act 1964). Man-made alterations to landscapes by climbers, such as the placement of fixed hardware on rock faces, are debatably permissible by the Wilderness Act of 1964 (Wilderness Act 1964).

10 Colorado Parks & Wildlife. (2019). Safety and Regulations. Retrieved from https://cpw.state.co.us/thingstodo/Pages/Safety-and-Regulations-Rock-Climbing.aspx

Discussion

My results indicate that most outdoor rock climbs in Colorado are located in Evergreen

Forests or Shrub / Scrub land. I also discovered that historically forested areas frequented by climbers may have experienced changes in landcover, converted into developed areas and shrub / scrub land since 1970. These findings are meaningful because they could be representative of greater land use change trends since the 1970s. This decrease in forested areas parallels demographic patterns of the last several decades; Colorado’s population has increased continually since the 1960s, and rock climbing has continued to grow in popularity over the same time (Achey 2002, Bowker et al 2016, US Census Bureau 2018). Outdoor rock climbing is hardly the driving force behind these land use changes, but must be considered within the broader context of increased outdoor recreational activity over the past several decades (Outdoor

Industry Association 2018). Colorado is one state in the greater American West that has experienced a dramatic increase in population growth of the 1990s as affluent people flocked towards landscapes rich in scenery, wildlife, and outdoor recreation (Hansen et al 2002).

It is immediately clear from GIS analysis that the majority of rock climbing areas in

Colorado are located on or nearby the Front Range, on the edge between Colorado’s plains and the iconic Rocky Mountains. This likely occurred because of presence of available climbable rock faces, but also because of human convenience; most outdoor climbing areas were established in close proximity to human civilization. There are, of course, outliers in this trend, including long, alpine climbs up Colorado’s 14,000+ ft. peaks. But the majority of areas— possibly even the most frequently climbed areas—are found near growing metropolitan areas including Denver, Boulder, Fort Collins, and Colorado Springs (USGS GAP 2016b).

My results also reveal that 39% of climbing areas are located in Evergreen Forest as of

2011, which could indicate a decrease in Evergreen Forests since 1970. This is notable because

Colorado’s evergreens have experienced heightened threats over the past two decades, including increased prevalence of bark beetles and extensive wildfires (Kulakowski & Veblen 2007, Bentz et al 2010). Bark beetle outbreaks range from Mexico to Alaska, and several recent outbreaks have been more severe and expansive than ever before (Bentz et al 2010). Additionally, within the context of climate change, population models suggest that certain bark beetle species including Dendroctonus rufipennis and Dendroctonus ponderosae are likely to increase in range as areas of the state warm and precipitation patterns change (Bentz et al 2010). Now is more important than ever to take precautions to protect Colorado’s native forests. Anthropogenic disturbance from outdoor recreation could build upon or even exacerbate preexisting threats to evergreen forests (Kulakowski & Veblen 2007).

Discrepancies in data resolution between the 1970 and 2011 data could alternatively imply that many climbing areas are located in boundary zones between ecosystems. Wherever there are discrepancies for landcover data points, it is possible that the landcover, itself, has not changed, but rather displays characteristics of more than one ecosystem / landcover type. These

“boundary zones” are also known as ecotones, transitional areas between adjacent ecological systems (Risser 1995). Plants with unique adaptations to tolerate a variety of environmental conditions often reside in ecotones, and changes to such species’ ranges can be indicative of greater climatic changes (Risser 1995, Wasson 2013). These regions generally often rich in biodiversity and thus beneficial to adjacent ecosystems (Risser 1995). Many climbing areas in

Colorado are located along its mountainous Front Range, or within the Rocky Mountains, often found on steep cliff faces surrounded by rapid changes in elevation and, consequently,

vegetation. Stricter regulation and care of climbing areas located in such ecotones could be considered priority areas for protecting Colorado’s native biodiversity.

The conversion of forest and shrubland to developed land observed is also indicative of greater threats to ecosystems that outdoor climbers visit. When previously undisturbed or minimally disturbed areas experience new development, native environments can suffer from habitat fragmentation. Development causing such fragmentation can range from trail building, to construction, to clear-cutting (Honnay et al 2014). Forest fragmentation in particular is known to change species composition, alter ecological interactions among species, and increase genetic drift and inbreeding in a given area (Honnay et al 2014, Magrach et al 2014). Anthropogenic disturbances like development can also increase the severity of wildfires for that region

(Kulakowski & Veblen 2007). Much like threats to evergreens, the effects of forest fragmentation provide more reason to manage outdoor recreation; as natural environments are under fire from all sides, we must prevent disturbances when and where we can.

Anthropogenic developed land is a major contributor to land use change between 1970 and 2011. 2011 NLCD and NTE data indicate that anywhere from 7.7% to 13% of Colorado’s climbing areas are located on “Developed Land” of some capacity. It is difficult to determine exactly what “Developed Land” implies for the environment, because humans can alter the environment and establish new building or open space developments in all kinds of ecosystems that may vary in elevation, temperature, annual rainfall, and dominant vegetation (USGS 2016).

Climbs located in developed areas are still significant, however, because environmental impacts from climbing build upon other negative anthropogenic impacts of development (Buchart et al

2010). Notable Colorado climbing areas located on “Developed Land” include routes in

Independence Pass, Boulder’s Flatirons, Garden of the Gods, Ute Valley, Eldorado Canyon,

Glenwood Canyon, Unaweep Canyon, Castlewood Canyon, Ouray, and more. Many of these

“Developed” areas were found to be under city, county, and state protection through land designation / ownership analysis. This means that government organizations like Boulder Open

Space & Mountain Parks, Colorado Parks and Wildlife, and even the National Park Service already work to conserve and preserve the majority of “developed” lands, including popular climbing areas. Despite these preexisting protections, the dangers of “edge effects” may still exist in these areas, and local land managers should be wary of additional development (Buchart et al 2010, Honnay et al 2014).

National Terrestrial Ecosystem data analysis also determined which threatened or endangered species reside in outdoor areas frequented by climbers. Astragalus cronquistii (Cronquist's Milkvetch) Astragalus debequaeus (DeBeque Milkvetch), and

Gymnorhinus cyanocephalus (Pinyon Jay) all reside in Colorado Plateau Pinyon-Juniper

Woodland, home to 15.6% of the state’s climbing areas. Similarly, Astragalus anisus

(Gunnison's Milkvetch) Astragalus ripleyi (Ripley's Milkvetch) Centrocercus minimus*

(Gunnison Sage-Grouse) Centrocercus urophasianus (Greater Sage-Grouse), and Lepidium huberi (Huber's Pepperwort) are all found in Rocky Mountain Lower Montane-Foothill

Shrubland, where 9.1% of Colorado’s outdoor climbing areas are located. Centrocercus minimus is of particular concern, as it is listed as Federally Threatened under the Endangered Species Act.

Finally, Colorado Plateau Pinyon-Juniper Shrubland, which accounts for 6.1% of the state’s climbing areas, is also habitat to Gymnorhinus cyanocephalus (Pinyon Jay). The habitat of these birds and low-lying plants are under potential threat from rock climbers, as past studies have proven that outdoor recreationalists can unintentionally extirpate birds from their habitats, and trample vegetation nearby recreative areas (Attarian & Pyke 2000, Cole 2004, Reed &

Merenlender 2008, Pickering et al 2009). Seasonal closures for birds during mating season as well as improved trail maintenance and signage could potentially mitigate these issues.

Analysis of land designation / ownership showed that 89% of climbing areas in Colorado are protected on some level by government agencies. The Bureau of Land Management controls

32% of climbing areas in the state, closely followed by the Forest Service at 31%. Another 5% of areas are federally managed as well, located within National Parks and National Monuments.

Regulations on rock climbing vary depending on National Park and recreation area. The State of

Colorado manages land that accounts for 5% of climbing areas, spanning four different state parks as well as some outlier state-owned land patches, such as the Vail Deer Underpass.

Similarly to federal regulation, no two parks are managed identically by the state. Local climbers have compromised with land managers in the past to establish regulations for individual climbing areas, such as Eldorado Canyon State Park (Access Fund 2018). Finally, city and county-owned land are significant regulators of outdoor climbing areas, at 10% and 5%, respectively (USGS GAP 2016a). This data is good news for the climbing community, as many government offices already work collaboratively with Local Climbing Organizations (LCOs)

(Access Fund 2018). Interactions like these have helped and can continue to help mitigate the environmental impacts of outdoor rock climbing. If environmental problems related to rock climbing arise in the future, suck as a decrease in population of jays, grouses and milkvetches, then standards for rock climbers should be altered even more as locals see fit.

Of Colorado’s climbing areas, 6.1% are located within Colorado’s Wilderness Areas.

Most Wilderness climbing areas are found within Rocky Mountain National Park Wilderness, with additional clusters of climbing walls in James Peak Wilderness and Holy Cross Wilderness.

Historically, the strict landscape preservation intentions of Wilderness Areas have fought head-

to-head with the goals of recreational climbers, as seen in the temporary climbing ban in Joshua

Tree National Park (and Wilderness Area) of southern California (Broxson 1995, Murdock

2010). Heavy, repeated use of outdoor climbs is evidenced to result in environmental degradation (Murdock 2010). Climbing is currently legal in all 3 Colorado Wilderness areas containing climbing areas, and Rocky Mountain National Park has already established specific climbing regulations: Seasonal closures for bird nesting, required permits for multi-day climbing excursions, and a prohibition on new fixed gear in the National Park. Regulations like these will be important to respect and maintain if land managers and climbers are to continue to cooperate in the future.

Areas with no known legal protections account for 11% of climbing areas in Colorado.

Although there are no known protections to these areas, local climbing communities may maintain these areas, unknown to governing bodies. No-protection areas mostly account for obscure bouldering areas such Guano Rock near the South Platte River and boulders near South

Park. The Mountain Project describes these areas as small boulders on privately owned land, the outskirts of national forest, or the fringe of urban areas. No-protection areas could easily threaten surrounding ecosystems if no legal obligations are set in place to maintain environmental quality.

However, with little available data for these areas, it is difficult to say if these areas are more “at- risk” than other heavily frequented climbing areas on government-regulated land.

Limitations of Study

My approach of comparing land cover and land use to climbing locations, rather than collecting primary data from one specific climbing area / set of areas, was the best strategy for a large-scale study with my available resources. However, this methodology is flawed in many

ways due to the lack of accurate, credible information on outdoor climbing tourism in Colorado, or anywhere in the world. This study has many sources of possible error. First, the data points used to represent geographic locations of outdoor climbs, sourced from the Mountain Project, are inherently flawed by a number of limitations. The Mountain Project is the only available geographic data for climbs in the state. The site was founded in 2005, and new routes, descriptions, photos, and information for climbs have been added to it by recreational climbers ever since. Many routes listed on The Mountain Project were established and climbed by 1970, but many were not. And, while the website lists the date when a climbing route or area was first posted by year, it does not include information on when routes were first established by climbers historically. For this reason, overlaying 1970s landcover with geographic climbing points from

2018 must have a certain degree of inaccuracy. To a similar extent, if there are any novel climbing areas in Colorado, the Mountain Project may not have uploaded data for those areas yet, limiting the amount of actual climbing areas this study is able to address.

Outdoor rock climbing is also inherently difficult to study because many climbers self- identify as enthusiasts of more than one outdoor sport, insofar as participating in more than one sport in a single outing or day (Outdoor Foundation 2018). Where should the line be drawn between the impacts of hikers and rock climbers, for instance? Many popular climbs in Colorado overlap with state, regional, and national parks which see visitors participating in a wide range of activities, including backpacking, hiking, hunting, fishing, mountain biking, horseback riding, camping, and climbing. Isolating the environmental effects of rock climbing as distinct from other sports would be a difficult task. This study’s approach, and recommended approach for future studies, is to take the angle of potential risks of the sport. Managing outdoor recreationalists of all varieties will be prudent for conserving wild, natural areas. Instead of

assigning blame to one sport in particular, a universal standard of best possible practices may be the better solution. This study has no hard evidence to correlate rock climbing with negative environmental impacts; rather, it determines notable threats the sport might pose to native environments and suggests top priorities for conserving biodiversity in outdoor climbing areas.

Suggestions for Future Study

A more accurate argument correlating climbing tourism with environmental degradation may be feasible if geographic climbing data points could be associated with number of annual climbers, or some scale of relative popularity. The Mountain Project’s database of over 100,000 routes nationwide includes “ticks” on routes where climbers can self-report attendance at an area, as well as the number of five-star-scale ratings per climb. Both may be used infer relative popularity of a given climbing area. The metadata used in this study instead utilized climbing

“wall” data, which did not include any information on the popularity of the climbing areas, or potentially how many visitors the sites saw annually. If “tick” metadata could be utilized, future studies could relate frequency of visitation to land use change, or any other environmental indicator. This could be a possibility for future research if a more sophisticated data extraction script were used to extract data from the Mountain Project’s API.

On a smaller scale, future studies could use different approaches to attempt to define a relationship between frequency of climbing tourism and severity of environmental impact. While climbing tourism statistics are not available for many outdoor climbing areas, certain local legal protections do record the number of annual climbers in given areas. The City of Colorado

Springs, for example, requires that every visitor to the Garden of the Gods Park intending to

climb submit a free Climbing Permit Application, providing the city with annual visitation statistics (Colorado Springs 2019).

A final alternative approach of study would be to examine the establishment of climbing areas in a state over time. There could potentially be a relationship between age of climbing area and severity of environmental degradation. Creating a more complex GIS database that could consider which climbing areas did and did not exist in the 1970s, for example, would provide a more accurate analysis for comparisons of rock climbing’s impact throughout time. There may even be a relationship between age of a climbing area and number of routes in that climbing area, although historic government regulations have banned the establishment of new routes in select small regions of the state. The general field of rock climbing within recreation ecology has ample opportunity for further research.

Application

Identifying potential threats of outdoor rock climbing on its surrounding environments is just the first step to managing those threats. Policy and practice both need to change if the climbing community is to support conservation in the future rather than hinder it. In 2019, the

United States is governed by an administration notorious for rolling back environmental regulations. This would appear an insurmountable obstacle to historic environmental thinkers like John Muir and Gifford Pinchot, who believed that public lands would suffer and degrade without federally implemented management (Fairfax, Huntsinger & Adelburg 1999). In reality, their predictions are not accurate. Small-scale, community-based land management can be very effective at conserving natural resources, particularly when decisions are made with public participation and based on scientific evidence (Fairfax et al 1999).

The United States is world-famous for its National Parks system and manages much more public land through the U.S. Forest Service and Wilderness Areas. Federal laws and executive orders have worked in tandem to set a precedent for conservation in the country. I argue that, while critical in preserving the resources still existing today, federal policy may not be necessary to manage outdoor recreation in the future. Resource users, themselves, may be the best people to take the reins of conservation through community-based management (Ostrom 2009).

Additionally, management which balances anthropogenic recreational use while maintaining ecological function reaps direct economic benefits for surrounding areas (Defries et al 2007).

Rock climbers in the United States have a rich history of community-based management already. The Access Fund is an organization founded by climbers who seek to acquire and protect outdoor climbing areas in the United States, and has been active since 1991 (Access Fund

2019). Access Fund representatives work to “reverse or prevent closures, reduce climbers'

environmental impacts, buy threatened climbing areas, help landowners manage risk and liability concerns, and educate the next generation of climbers on responsible climbing practices that protect access” (Access Fund 2019). Its membership has grown from just a few hundred people in the 1990s, to over 17,000 in 2018 (Access Fund 2018). This nationwide organization has influence in 43 states and influences 117 LCOs that function on smaller scales, but are able to source funding from the greater Access Fund.

Outdoor rock climbers have been self-organizing to mitigate their environmental impacts since the 1980s (Achey 2002, Access Fund 2019), but that momentum may have decreased in recent years as climbing has become more popular than ever before (Outdoor Industry

Association 2017). Gone are the days of climbers as an obscure, counter-culture minority (Taylor

2006). A film about a rock climber won the 2018 Academy Award for Best Documentary; indoor sport and speed climbing are set to be included as Olympic sports in 2020, and an increase media exposure only stokes the positive feedback loop of the sport’s growth (Outdoor Industry

Association 2017). Perhaps just as notable is the increase in climbing walls on university campuses, which make climbing more affordable and accessible to the college demographic

(Eldorado Rock Walls 2019). Although college gyms only make climbing more accessible to a relatively elite, privileged class, that is the very class of people who can afford to continue climbing as they move on to their adult lives, considering the high cost of equipment for outdoor climbing (Outdoor Industry Association 2017, Access Fund 2018). As the sport has grown and even more climbers brave the wilderness, less experienced climbers impact surrounding environments. New climbers do not necessarily learn to climb outdoors from mentors who encourage stewardship, creating an unfortunate opportunity for climbing culture to shift. The

fierce fights of the “good old days” for land rights are slowly being replaced by a generation that feels entitled to climb anything, at any time, at any cost (Wilkinson 2015).

One factor that may contribute to modern climbers’ increasing apathy towards conservation is a shift in ideology. The Environmental Movement of the 1970s brought with it an increase in outdoor adventurers and subsequent growth in the climbing community (Achey 2002,

Taylor 2006). It also provided a framework to change the mindset of climbers to a new ideology.

The outdated, environment-dominating mindset of early mountaineers was replaced by a desire to preserve and protect the environment for the benefit of all, including future generations. But as we approach half a century passed since the birth of the Environmental Movement, I would argue that newer generations have not learned to value nature in the same way. Younger generations who grew up enjoying the public lands protected by generations prior may lack feelings of connection with and gratitude for the environment (Wilkinson 2015). Modern climbing culture has returned to an environment-dominating mindset of the sport’s early days; mastery of the human body and the natural environment are now fundamental to the sport

(Abramson & Fletcher 2007). For many modern adventurers, nature is not a location for quiet contemplation and connection. Instead, “wild places often are treated as outdoor gymnasiums whose highest touted value is delivering rushes of adrenaline” (Wilkinson 2015).

Community-based management of outdoor rock climbing is an accessible solution achieve a future that balances outdoor rock climbing with conservation of biodiversity and ecological balance. Not only do LCOs provide pathways for specific, localized concerns to be identified and mitigated; they foster community involvement and stewardship that can be passed on to newer generations of climbers, and even reverse anti-conservation, entitled ideologies.

Historically, the climbing community has a track record of recognizing ecological degradation and improving their practices (Access Fund 2019). Although a notable cultural shift in the climbing community occurred over the past several decades, that shift has the potential for reversal. If LCOs target new climbers with educational resources and introduce avid new outdoorspeople to principles of conservation, the environmentalist spirit of the 1970s could very well return (Schild 2016).

Possible management strategies that Colorado LCOs should implement, indicated by the species and ecosystems at risk identified in this study, and supported by past research of rock climbing, include:

• Seasonal closures for wildlife mating and/or habitat (Klein, Humphrey, & Percival 1995, Attarian & Pyke 2000)

o Particular priority to be granted to the Pinyon Jay, Gunnison Sage-Grouse, and Greater Sage-Grouse (see Figure 11)

• Sections of cliff-face permanently closed for climbing to preserve cliff-face biodiversity (Clark & Hessl 2015, Volger et al 2017, Lorite et al 2017)

• Establish more developed trails to reduce soil erosion and runoff and maintain protected habitat for at-risk plant species (McMillan & Larson 2002, Carr 2007, Rusterhok et al 2011)

• Educational signs at every climbing trailhead to encourage visitors to stay on-trail, prevent littering (Attarian & Pyke 2000, Schild 2016, Access Fund 2018)

• Boot/shoe cleaner brushes at trailheads to reduce the spread of invasive seeds and spores (Cole 2004, Davidson et al 2005, Pickering et al 2009)

• Required fees at popular climbing destinations to help fund protective resources and maintain facilities

The above policies would help lessen any potential negative impacts of outdoor climbers on at-risk species in Colorado climbing areas, help preserve cliff-face biodiversity, help reduce the spread of non-native pathogens, reduce soil runoff, encourage stewardship, and establish a system for funding future conservation efforts, all while co-existing with recreational climbing. These are also policies that could be implemented and potentially regulated by

LCOS, and could find additional support from government land managers like the BLM and

Forest Service. It should be noted that, ideally, no measure would be passed without the education and consent of climbers in an area. At the very least, prominent members of LCOs should approve of any changes implemented to popular climbing areas.

Conclusion

Rock climbing accounts for an increasingly large part of the outdoor recreation landscape and economy in the United States each year. From college climbing walls to Oscar-winning documentaries, rock climbing has entered the public eye and permeated culture in the 21st

Century more than ever before. This paper is the first known of its kind to attempt to analyze the ecological effect of rock climbing through geospatial analysis. A GIS database was created overlaying U.S. Geological Survey landcover and land ownership data with point data of outdoor climbing locations in Colorado. The analysis determined the most common environments frequented by climbers, identifying concerns for each ecosystem, and describing the legal protections already in place for some of such environments. Evergreen Forests may be under threat from climbers, already prone to destruction from wildfires and bark beetles. Additionally, seven species reported threatened (4 Milkvetch species, 2 Sage-Grouse species, and the Pinyon

Jay) were found to occur in Colorado’s ecosystems frequently visited by climbers: Colorado

Plateau Pinyon-Juniper Woodland, Rocky Mountain Lower Montane-Foothill Shrubland, and

Colorado Plateau Pinyon-Juniper Shrubland. GIS analysis also revealed that 89% Colorado’s climbing areas are located on government-protected lands, with 68% federally managed, 10% city-managed, 6% state-managed, 5% county-managed, and 11% unprotected. These preexisting protections should stand to help climbers with conservation pursuits in the future.

Rock climbing is difficult to study academically because of its overlap in range with other outdoor sports, as well as lack of annual visitor data for climbing areas. However, this study utilizes and recommends the approach of identifying potential ecological concerns of rock climbers, as indicated by the location of climbing routes. It seeks to help establish a universal

standard of best possible practices in sensitive native environments, rather than assign blame to specific outdoor sports.

Small-scale, community-based management is likely the best strategy to mitigate impacts of rock climbing due to bipartisan gridlock in federal, and occasionally state, governments. Over

100 Local Climbing Organizations already exist in the United States and could feasibly implement the suggested management strategies described in this paper. It is my hope that local policy change comes hand-in-hand with a cultural and ideological shift in the climbing community, whose ideologies have somewhat devolved in recent years from environmentalist to environment-dominating philosophy. Physical and ideological changes are both necessary for the outdoor climbing community to sustainably coexist with its surrounding ecosystems.

Recreational climbing accounts for just one small fraction of anthropogenic disturbance on Earth’s environments. A vast variety of ecosystems worldwide are already experiencing the harsh impacts of natural disasters, anthropogenically introduced diseases, and invasive species.

Global climate change disrupts the ecological balance of the planet as we know it and is predicted to worsen in years to come. Ecosystems carefully developed over hundreds of thousands of years by natural selection are facing threats like never before. But the large extent of anthropogenic impacts on the environment is the exact reason humans should strive to lessen their impacts to the best of their ability.

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