Protected areas worldwide are impacted by human activities within their boundaries. Despite having the highest level of protection in the US, wilderness areas are still vulnerable to ecological impacts. We compiled population, population growth rate, median travel time, wilderness size, wilderness proximity, relative accessibility, trail density and an amenity index to generate a Day-Use Vulnerability Index (DUVI) for 722 wilderness areas in the continuous US (CONUS). Using DUVI, we found that the Mount Timpanogos wilderness area in Utah, the Glacier View wilderness area in Washington, the J.N. Ding Darling wilderness area in Florida, the Philip Burton wilderness area in California and the Birkhead Mountains wilderness area in North Carolina were most likely to have ecological impacts from high day-use. Our findings provide a system for evaluating daily use of wilderness areas that could be paired with visitor counts in the future to improve predictions. Growing human populations and recreation are worldwide issues, suggesting that this framework could also be of interest to stakeholders outside the CONUS.

This study explores the impact of human trampling on moss and lichen dominated communities of Maritime Antarctica. A simulation of trampling was performed on previously unaffected plots of different terricolous cryptogamic assemblages at Byers Peninsula, Livingston Island. The communities studied were: 1) a uniform moss carpet, 2) a heterogeneous moss assemblage composed of hummocks and turfs, and 3) a fellfield lichen community. All communities analysed were extremely sensitive but different denudation processes were observed. None of the plots maintained 50% of initial coverage after 200 pedestrian transits. Even very low trampling intensity resulted in disturbance at all plots. Sensitivities of the different communities were identified in order to formulate recommendations for minimizing the trampling impacts. In our study the lichen dominated community on dry exposed soils exhibited the lowest resistance to trampling. For moss communities, lower resistance was found in peat soils with higher water content and biomass. With the current trend of increasing human presence in Antarctica, we predict that the cumulative impacts of trampling over future decades will adversely affect all types of moss and lichen communities.

The expansion and proliferation of backcountry campsites is a persistent problem in many parks and protected areas. Shenandoah National Park (SNP) has one of the highest backcountry overnight use densities in the USA national parks system. SNP managers implemented a multi-option backcountry camping policy in 2000 that included camping containment with established campsites. These actions were intended to reduce the number of campsites and the area of camping disturbance at each site. This paper describes a longitudinal adaptive management assessment of the new campsite policies, applying quantitative measures of campsite conditions to evaluate the efficacy of management interventions. Physical campsite measurements combined with qualitative visitor interviews indicated SNP had successfully reduced the number of campsites and aggregate measures of camping-related disturbance in the Park, while minimizing the use of regulations, site facilities and staff resources. Implications for managers of other protected areas are that an established site camping policy can minimize camping disturbance, including the number and size of campsites, provided managers can sustain rehabilitation efforts to close and restore unneeded campsites. Experiential attributes, such as the potential for solitude, can also be manipulated through control over the selection of established campsites. Integrating resource and social science methods also provided a more holistic perspective on management policy assessments. Adaptive management research provided a timely evaluation of management success while facilitating effective modifications in response to unforeseen challenges. Conclusions regarding the effectiveness of a visitor impact containment strategy involving an established site camping option are offered.

Recreational camping in wilderness areas causes a number of biophysical impacts, including loss of woody debris through campfires. Although extensive research has documented trampling impacts to vegetation, few studies have explored the extent of woody material depletion. This study adapted planar transect methods to measure the relative loss of fine (<0.6 cm), small (0.6 to 2.5 cm), medium (2.6 to 7.6 cm) and large (>7.6 cm) diameter materials in three concentric rings extending 0–5 m, 5–10 m and 10–15 m from the centre of 58 campsites in different environments ranging in elevation from 1250 to 2225 m in the Cascades Mountains in Oregon, USA. Compared to matched controls, losses were greatest for small (40%) and medium-sized (63%) materials, but were evident for fine (25%) and large (30%) materials as well. Surprisingly, depletion (across all sizes) was no greater in the centre of sites than in the outer measurement ring, even though the outer ring was often in intact vegetation. This suggests that impacts on woody debris extend beyond those impacts to vegetation typically monitored at campsites. Such recreational impacts to woody debris have rarely been systematically described. However, research on woody debris removal related to forest management indicates possible ecological effects of fuelwood consumption.