Cliff ecology: Extent, biota, and recreation of cliff environments in the New River Gorge, WV

The New River Gorge National River (NERI) contains an extensive network of exposed cliff-forming sandstone units, the most extensive in West Virginia and possibly within the entire Appalachian range. These cliff resources are critical to NERI\u27s national significance, and contain specialized and potentially rare plant communities (Vanderhorst 2001; Mahan 2004; Vanderhorst, Jeuck, and Gawler 2007). This project investigates the spatial distribution of cliffs, associated plant (vascular and non-vascular) and lichen communities, and the impacts to cliff environments caused by recreational rock climbing.;Using LiDAR in a GIS, we mapped all cliffs in the northern extent of NERI, from Keeney\u27s Creek to the Hawks Nest Dam. We randomly selected 36 potential cliff outcrops along gorge slopes to measure structure and inventory cliff face species along all outcrop-forming sandstones. We also sampled 111 Nuttall Sandstone cliffs desirable for rock climbing to assess impacts to cliff environments at three positions: cliff base, face, and top. We randomly selected 79 established rock climbs (experimental) stratified by climb difficulty, potential use intensity, and aspect. In addition, we selected 32 unclimbed sites (control) deemed climbable and stratified by estimated difficulty and aspect. We measured species richness, soils depths, hardened zone (compacted area) lengths, and evidence of anthropogenic disturbance to analyze recreational impacts by climb difficulty, use intensity, and climb style ( traditional or sport ).;Based on LiDAR, we estimate that there are 97 linear kilometers of exposed sandstone cliffs in the northern extent of NERI. Nuttall Sandstone differs in extent, structure and competence from the Raleigh, Guyandot, and Pineville Sandstones. Incompetent cliffs are more heterogeneous and sustain greater vascular species richness and frequency compared to sites desirable for rock climbing. Stepwise regression indicates 40% of overall cliff face species richness is determined by cliff angle and topography. We recorded 249 total species on cliff faces plus an additional 109 on cliff tops and base. Total species richness on cliff face ranges from 0 -- 49. Common cliff face plants include: Asplenium montanum Wild., Betula lenta L., Lasallia pennsylvanica (Hoffm.) Llano, Phsycia subtilis Degel., Leucobryum glaucum (Hedw.) Angstr., and Dicranella heteromalla (Hedwig) Schimper. Species of special interest include: Danthonia sericea Nutt., Dichanthelium acuminatum (Sw.) Gould & C.A. Clark ssp. columbianum, Chrysothrix susquehannensis Lendemer & Elix, Umbilicaria americana Poelt & T.H. Nash, Dicranum condensatum Hedw., and Brothera leana (Sull.) Mull. Hal.;Impacts to cliff environments from rock climbing are conditioned by climb difficulty, use intensity, and to some extent, climb style. Climb difficulty is highly correlated with cliff structure, with significant declines in topographic frequency and steeper cliff angles associated with more difficult climbs (r 2 = 0.63; P \u3c 0.01). Cliff face species richness declines with increases in climb difficulty (climbed or unclimbed) as well as with increased use intensity. A general linear model based on difficulty and use intensity explains 50% of the variability in total cliff face species richness. Of all cliff positions we investigated, cliff bases are most impacted by climbing, regardless of use intensity, difficulty, or style. Impacts to cliff tops are uncommon and are confined to low difficulty, popular, traditional climbs.;Sites desirable for rock climbing represent a subset of cliffs in NERI, differing from randomly selected and incompetent cliffs in structure and vascular richness and abundance. Rock climb difficulty (e.g., cliff structure) and use intensity are clear predictors of diversity and can be used to guide management. Future development of climbs on competent, low angle cliffs should be limited to preserve the most diverse environments. Cliff bases are the most consistently impacted, where beginner level climbs sustain the greatest impacts to soils, bryophyte species richness, and hardened zone lengths. Impacts to cliff tops are infrequent, occurring on less that 20% of sites and are confined to a subset of climbing (classified as: high use, traditional, \u3c5.9). To prevent further impacts to sensitive cliff tops, management should target current and future beginner level, highly popular, traditional style climbs and establish a perimeter to impede enhanced impacts. We suggest that trails at base and top be rerouted away from cliffs into the contiguous forest to limit unnecessary traffic along sensitive and unique cliff edges. We recommend the judicious placement of climbing anchors at moderate to high use sites, specifically placed \u3e2 m below cliff top above which height diversity is greatest. In addition, we recommend outreach to educate climbers about the negative effects of topping out (climbing on the top of the cliff rather than using anchors). Similarly, other recreational uses at cliff tops should be limited, especially trails and lookouts