39 Wildlife responses to human recreation: modelling the effect of visitor frequency on ungulate distance to hiking trails in the Swiss National Park
Recent years have seen a steady increase in outdoor recreation, especially to the most pristine areas, like national parks. Thus, park managers are challenged to balance nature experience and conservation. Comprehensive research has been conducted on how recreational activities influence wildlife. In this study, we investigated how daily visitor numbers affect distances of Alpine chamois (Rupicapra rupicapra) and red deer (Cervus elaphus) to hiking trails, in an alpine area that has been strictly protected for over 100 years, including a hunting ban, and without large predators resident. We expected some degree of habituation and predicted that (1) animals stay closer to trails, when trapped compared to immobilised, since the trapping method may select for corresponding behavioural traits; (2) animals stay closer to trails later in the season and when they are older; (3) animals stay further away from the trails, when they are in open habitat. We performed geographical and statistical analyses, separately modelling GPS locations from 36 chamois and 20 red deer as a function of visitor numbers and several environmental and individual specific factors over a period of 9 years within an additive model framework. In both final models visitor numbers had no effect on distance, and elevation was the most important predictor variable, affecting distance from trails the strongest. Moreover, modelled effects for both species differed noticeably. Predicted distances from trails had large margins of uncertainty. However, some trends and distinct patterns crystallised: chamois, generally, stay further away from trails than red deer; contrarily, there was virtually no difference in distance for both capture method and cover. In summary, we conclude that by using GPS locations alone it is difficult to disentangle all important factors affecting wildlife responses to human recreation. Effective management could account for that by adjusting hiking trail networks or providing visitor behaviour guidelines.
Note: This study was carried out as a master’s thesis and part of a larger collaboration project about optimising national park management with regards to nature conservation and tourism. Data was kindly provided by the Swiss National Park and stemmed from its long-term visitor and ungulate monitoring.