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Quaking aspen (Populus tremuloides Michx.) landscapes are valued for their biodiversity, water retention, fire mitigation, aesthetics, and recreation opportunities. Across North America, some aspen populations are experiencing population declines as they face uninhibited ungulate browsing, drought, fire suppression, insects, disease, and inappropriate management. Increased human development and recreational use within aspen landscapes can serve as additive stressors, though there is a dearth of literature examining these elements. At a popular recreational area in Utah, USA, identifying the cause of apparent decline within a larger aspen community is complicated by development upstream and recreation-related activities. We sought to (1) assess the overall condition of the aspen at the site, (2) understand key variables that influence aspen conditions, and (3) elucidate how aspen fitness varies across the site. We collected data from forty-five plots using established aspen sampling methods, including ungulate presence, tree characteristics, soil chemistry, and environmental descriptors. Results suggest that a combination of higher levels of browsing and elevated soil sodium may be causing premature mortality and limiting aspen recruitment in a portion of the study area. These findings will inform future management at this site, as well as similar recreational forest settings experiencing compound stressors. [ABSTRACT FROM AUTHOR]

Parks and Protected Areas (PPAs) across the Intermountain West region of the United States have observed an increasing trend in visitation in the past decade. Management of visitors' vehicles as much as the visitors themselves has created a challenge for managers. Experiencing PPAs by personal vehicle is a popular recreation experience. However, as PPAs accommodate historic levels of visitation, the infrastructure to accommodate these vehicles is strained. In response to periods of especially high use in the summer months, Rocky Mountain National Park (ROMO) actively limits access to the Bear Lake Corridor (BLC), one of the most popular day use areas of the Park. Because of limited parking infrastructure and capacities to provide a safe and quality visitor experience, ROMO redirects (i.e., diverts) vehicles away from the BLC. In July 2017, to examine the effect of this management intervention on visitor spatial behavior, participants intending to enter the BLC were given a Geographic Positioning System (GPS) device to track their movement throughout their visit to the Park. We performed a Distributive Flow analysis with the GPS data to understand the diversion's effect on traffic patterns of visitor vehicles diverted from the BLC. This study found that 21.2% of diverted visitor vehicles returned to the BLC after being redirected and 9% left the Park entirely, suggesting that there is a lack of substitutability for some visitors within the Park for the experience found along the BLC. During a period of redirection, Moraine Park, Endovalley, and Trail Ridge Road received increased levels of visitation as use was diffused across the Park, which may warrant increased monitoring of changes to the experiential and biophysical conditions in these locations. Diverted visitor vehicles made more stops, drove further distances and for a longer period of time than non-diverted visitor vehicles, but there was no significant difference in the length of time spent at points of interest within the Park. While the diversion was effective in temporarily reducing congestion in the BLC, its effect on visitors' spatial behavior suggests that overall aggregate impacts to park resources and experiential conditions may be increasing as a result. [ABSTRACT FROM AUTHOR]

Reliable maps of species distributions are fundamental for biodiversity research and conservation. The International Union for Conservation of Nature (IUCN) range maps are widely recognized as authoritative representations of species' geographic limits, yet they might not always align with actual occurrence data. In recent area of habitat (AOH) maps, areas that are not habitat have been removed from IUCN ranges to reduce commission errors, but their concordance with actual species occurrence also remains untested. We tested concordance between occurrences recorded in camera trap surveys and predicted occurrences from the IUCN and AOH maps for 510 medium- to large-bodied mammalian species in 80 camera trap sampling areas. Across all areas, cameras detected only 39% of species expected to occur based on IUCN ranges and AOH maps; 85% of the IUCN only mismatches occurred within 200 km of range edges. Only 4% of species occurrences were detected by cameras outside IUCN ranges. The probability of mismatches between cameras and the IUCN range was significantly higher for smaller-bodied mammals and habitat specialists in the Neotropics and Indomalaya and in areas with shorter canopy forests. Our findings suggest that range and AOH maps rarely underrepresent areas where species occur, but they may more often overrepresent ranges by including areas where a species may be absent, particularly at range edges. We suggest that combining range maps with data from ground-based biodiversity sensors, such as camera traps, provides a richer knowledge base for conservation mapping and planning., (© 2024 The Authors. Conservation Biology published by Wiley Periodicals LLC on behalf of Society for Conservation Biology.)