Introduction
For a long time the ecology of animals inhabiting high-mountain habitats was little studied because of the inaccessibility of these environments (Krajick, Reference Krajick1999). As a consequence, the significance of mountains in the preservation of biological diversity was frequently underestimated. The habitat and climatic conditions of high mountains support species with narrow and highly specific ecological requirements (Körner, Reference Körner2004; Spehn & Körner, Reference Spehn and Körner2005). High-mountain species, formerly relatively undisturbed by human influence, have in recent decades been subjected to ever greater anthropogenic pressure. Habitats are being transformed and degraded as a result of mining, overgrazing, climate change and other influences, and tourism is having increasingly deleterious effects on the natural resources of high mountains, including in protected areas. The spatial and temporal concentration of tourism, tourist infrastructure, forms of recreation and the behaviour of tourists may all have potentially negative impacts on wild species and their habitats (Gössling, Reference Gössling2002; Zaręba, Reference Zaręba2008).
One of the most significant threats to high-mountain environments comes from people entering them (Beale & Monaghan, Reference Beale and Monaghan2004), and from the noise they make and their motor vehicles (Holmes et al., Reference Holmes, Knight, Stegall and Craig1993). Activities such as skiing, motoring, hiking and climbing can all contribute to the degradation and loss of mountain habitats and to changes in the behaviour of the species living there (Gander & Ingold, Reference Gander and Ingold1997; Camp & Knight, Reference Camp and Knight1998a,Reference Camp and Knightb; Thiel et al., Reference Thiel, Jenni-Eiermann and Palme2005, Reference Thiel, Ménoni, Brenot and Jenni2007, Reference Thiel, Jenni-Eiermann, Braunisch, Palme and Jenni2008; Zwijacz-Kozica et al., Reference Zwijacz-Kozica, Selva, Barja, Silván, Martínez-Fernández, Illera and Jodłowski2013). As they often have restricted ranges, these species are sensitive to environmental change. Increasing human disturbance in their habitats may have potentially catastrophic consequences (Ewers & Didham, Reference Ewers and Didham2006).
The Tatra Mountains are one of the few mountain ranges in central Europe that support high-mountain flora and fauna. Human activities have influenced this area for > 200 years but the region is now protected as a national park. The only human pressure still affecting this area comes from tourism: hiking, climbing, caving and skiing, along with associated amenities such as hostels, the mountain rescue service, restaurants and transport. As many as 2.7 million people visit the Polish Tatra Mountains every year.
As a result of the construction in 1936 of a cable car to Kasprowy Wierch, a peak in the central Polish Tatra Mountains, the area around it became anthropogenically transformed. In addition to the upper terminal of the cable car there are two ski lifts and ski pistes (Gąsienicowa Valley and Goryczkowa Valley) and a weather station. Every day in the summer 2,000–3,000 people reach the summit on foot (Czochański, Reference Czochański and Partyka2002) and until recently the cable car brought an additional 1,200–1,300 people daily (Skawiński & Krzan, Reference Skawiński, Krzan and Borowiec2002). The large numbers of people visiting these mountains could be having an adverse impact on this environment, including on the Tatra chamois Rupicapra rupicapra tatrica (Zwijacz-Kozica et al., Reference Zwijacz-Kozica, Selva, Barja, Silván, Martínez-Fernández, Illera and Jodłowski2013). Although the chamois Rupicapra rupicapra is categorized as Least Concern on the IUCN Red List (Aulagnier et al., Reference Aulagnier, Giannatos and Herrero2008), the subspecies R. rupicapra tatrica is categorized as Critically Endangered in the European Mammal assessment and in the Polish Red Data Book (Gąsienica-Byrcyn, Reference Gąsienica-Byrcyn and Głowaciński2001).
The infrastructure of the cable car to Kasprowy Wierch was modernized during 2007–2008, with the cable cars, their support masts and cables changed or rebuilt, to speed the flow of passengers and to carry more people to the mountain tops. In effect, an unplanned experiment has taken place, increasing human pressure in a strictly protected high-mountain habitat. The objective of the present research was to assess the influence of the increasing number of people on the numbers and distribution of the chamois. Our hypothesis was that the increase in mass tourism in the areas inhabited by chamois had increased the distance between these animals and the places visited by people.
Study area
Lying in the central western Carpathians, the Tatra Mountains are the highest mountain massif between the Alps and the Caucasus. The area has an alpine landscape with altitudinal zonation of climate and vegetation, including alpine meadows and a sub-nival zone. The mountains cover an area of c. 800 km2, c. 20% of which lies within Poland. The highest peak is Gerlach (2,655 m).
The Tatra Mountains are protected in their entirety as national parks: the Tatranský Národný Park in Slovakia (designated in 1949) and the Tatrzański Park Narodowy (Tatra National Park) in Poland (designated in 1954). On the basis of their biodiversity and unique geomorphology the Tatra Mountains are a UNESCO World Biosphere Reserve and are included in the Natura 2000 network of protected areas in Europe.
The peak of Kasprowy Wierch (1,987 m) in the central part of the Polish Tatra Mountains rises at the meeting point of three extensive valleys. It has a temperate but high-mountain climate. The mean annual air temperature is −0.7°C, snow covers the ground for an average of 221 days per year, and the mean annual precipitation is nearly 1,800 mm (Limanówka et al., Reference Limanówka, Cebulak, Cichocki, Kilar and Pyrc2008).
The modernization of the infrastructure of the cable car system to Kasprowy Wierch during 2007–2008 included support masts and cables and a doubling of the size of the cable cars. The works required c. 6 months, with the use of heavy equipment that generated extensive noise, supply of materials and the presence of workers.
Methods
The field work was carried out before (1999–2001) and after (2008–2010) modernization of the cable car system. In both periods an 18 km transect through potential chamois habitat, across altitudes of 1,023–2,051 m, was surveyed (Fig. 1). In each survey the sizes and positions of chamois herds were recorded. Within the herd, sex and age (adult, first-year calf, second-year young) of individuals were recorded. Surveys were carried out twice per week during 06.00–18.00 between the beginning of June and the end of September. A non-stop walk along the transect took 6–7 hours but could take double this time when there were chamois to be observed. A total of 103 surveys were carried out during 1999–2001 and 104 during 2008–2010. The positions of the sighted herds were marked on 1 : 10,000 scale maps, from which a vector layer was produced.
Using the vector layer containing the chamois records and an orthophotomap of Tatra National Park (for 2009, resolution 25 cm), the distances of the observed animals were measured to the nearest hiking trail, the upper cable car terminal on Kasprowy Wierch, the cable car support masts and cables, and the ski lifts and pistes in the Gąsienicowa and Goryczkowa Valleys. The measurements were made using ArcGIS v. 9.1 (ESRI, Redlands, USA), ignoring topographic irregularities.
To compare tourist pressure between the two research periods we used ticket sales from Tatra National Park and the Polish Cable Car Company; i.e. the number of people entering the National Park on foot and of passengers carried to Kasprowy Wierch, respectively. Monitoring data for Tatra National Park were used to compare the number of chamois between the two periods across the entire mountain range. These data were collected using a survey method established in 1932 by J. Műller (Chudík, Reference Chudík1969), in which an annual count, during October–November, is conducted simultaneously across the entire Tatra Mountains.
Statistics were calculated with Statistica v. 8.0 (StatSoft, Tulsa, USA), following Zar (Reference Zar1999). A squared transformation was used to normalize data. The Student's t-test was used to examine differences in the distance of chamois herds to infrastructure before and after modernization, Pearson's correlation coefficient to explore the relationship between herd size and distances to infrastructure for each period, a χ2 test to examine differences in sex ratio between the two periods, and a Mann–Whitney U-test to analyse differences in the number of second-year young within a herd between the two periods.
Results
During 1999–2001 a mean of 2,331,762 ± SD 107,003 people visited Tatra National Park annually. This number did not differ significantly (t = –0.44, P = 0.683) from the number of visitors during 2008–2010 (mean 2,391,157 ± SD 208,565 per year). During 1999–2001, prior to the modernization of the cable car, a mean of 323,125 ± SD 43,993 people were transported annually to the summit of Kasprowy Wierch by cable car; this rose to a mean of 479,915 ± SD 62,862 per year during 2008–2010, after modernization. This increase was significant (t = –3.54, P = 0.024). The mean annual chamois population in the entire Tatra National Park during 1999–2001 was 70 ± 1 SD individuals, significantly fewer (t = –10.97, P = 0.000) than during 2008–2010 (mean 157 ± 14 SD).
Before the cable car modernization, chamois were recorded on the Kasprowy Wierch massif 64 times but after modernization only 36 times (Fig. 1). There was a significant decrease in the mean chamois herd size between 1999–2001 and 2008–2010 (Table 1). After modernization the distance between the sites where chamois were recorded and parts of the tourist infrastructure changed: there was a significant increase in the distance between the chamois and the summit cable car station, cable car supporting masts and cables, and the ski lifts and pistes in the adjoining valleys (Table 1). The only parameter unchanged was the distance to the hiking trails.
At the same time, there was a change in the relationship between herd size and distance to parts of the tourist infrastructure. Prior to the cable car modernization, chamois herd size was inversely proportional to distance from the tourist infrastructure: larger herds were seen at closer distances (Table 2). After modernization, however, there was a positive correlation between herd size and distance from three of four elements of the tourist infrastructure (Table 2). Sex structure differed significantly between the two periods (χ2 = 71.79, P = 0.000). Before the cable car modernization males and females constituted 8.4 and 91.6%, respectively, (n = 155) of all recorded adult chamois. After modernization males and females constitute 14.0 and 86.0%, respectively, (n = 50) of all recorded adults. The number of second-year young accompanying female herds differed significantly between study periods (Z c = 4.35, P = 0.000). Before the cable car modernization the median number of second-year young was 2 (quartiles25–75 = 2–3, range = 0–4, n = 48); after modernization the median number of second-year young was 0 (quartiles25–75 = 0–1, range = 0–3, n = 20).
Discussion
The results of this work show that a 50% increase in the number of tourists carried by cable car to the chamois’ habitat has led to a decrease in herd size and an increase in the distance separating the animals and the cable car infrastructure. Only the distance between the chamois and the hiking trails has not changed significantly. More people now congregate near the summit cable car station and ski lifts/pistes, putting greater pressure on the adjacent areas, but this has not caused more people to go onto the hiking trails.
Human activities in high-mountain environments disturb animals (Cederna & Lovari, Reference Cederna, Lovari and Lovari1985; Patterson, Reference Patterson1988; Ingold et al., Reference Ingold, Schnidrig-Petrig, Marbacher, Pfister and Zeller1996; Pépin et al., Reference Pépin, Lamerenx, Chadelaud and Recarte1996; Schnidrig-Petrig & Ingold, Reference Schnidrig-Petrig and Ingold2001). Repeated events elicit the most serious effects: the animals ultimately become accustomed to them, losing their fear and decreasing vigilance towards other unpredictable disturbances and dangers (Hamr, Reference Hamr1988; Gander & Ingold, Reference Gander and Ingold1997). As a result of human disturbance, chamois have less time for foraging or resting (Enggist-Düblin & Ingold, Reference Enggist-Düblin and Ingold2003). This significantly raises the amount of energy they have to expend on moving away from sources of disturbance, and prolongs the amount of time devoted to vigilance (Parker et al., Reference Parker, Robbins and Hanley1984; Bradshaw et al., Reference Bradshaw, Boutin and Hebert1998). Sibbald et al. (Reference Sibbald, Hooper, McLeod and Gordon2011) demonstrated that animals may change their behaviour and dietary composition by abandoning food-rich areas. The result is that habitats are effectively lost, and that interspecific and intraspecific competition may increase in other areas, where food availability may be limited (Gordon & Illius, Reference Gordon and Illius1989). This is a common situation in mountains, where the growing season is relatively short and the range of suitable habitats limited by altitudinal zonation. In addition, disturbance of the animals during the rut may lead to a decrease in numbers, which in the longer term may threaten population survival (Ellenberg et al., Reference Ellenberg, Setiawan, Cree, Houston and Seddon2007).
Physiological reactions in wild animals stressed by pressure from tourists give rise to changes in the chemical composition of the blood (Tapper, Reference Tapper2006). Elevated levels of corticosteroid derivatives were found in the droppings of chamois from Tatra National Park (Zwijacz-Kozica et al., Reference Zwijacz-Kozica, Selva, Barja, Silván, Martínez-Fernández, Illera and Jodłowski2013). Of all the herds living in the Park, those around Kasprowy Wierch are exposed to the strongest tourist pressure (Jamrozy & Pęksa, Reference Jamrozy and Pęksa2004). The existence of herds in this area probably depends on the animals’ ability to adapt to the large numbers of tourists by reducing the escape distance from humans to c. 25 m (Jamrozy et al., Reference Jamrozy, Pęksa, Urbanik and Gąsienica-Byrcyn2007). This is a much smaller distance than that of chamois in the Swiss Alps, where the escape distance of males with respect to humans was 103–180 m (Gander & Ingold, Reference Gander and Ingold1997). In Tatra National Park, therefore, large herds of chamois could formerly be seen relatively close to places visited by people. But the marked increase in visitor numbers following modernization of the cable car has caused the distances between the chamois and people to increase, and larger herds to abandon these sites.
The increase in distance is the result of human pressure (Gander & Ingold, Reference Gander and Ingold1997; Papouchis et al., Reference Papouchis, Singer and Sloan2001). Regardless of the type of human activity, its initial adverse impact is to reduce the chamois’ range. The chamois of the Kasprowy Wierch area, which until recently occupied one of the smallest suitable habitat patches in Tatra National Park (in the growing season it was c. 2.5 km2; Jamrozy & Pęksa, Reference Jamrozy and Pęksa2004), abandoned most of this area following modernization of the cable car.
Fragmentation and habitat loss are fundamental threats to global biodiversity. They can isolate and reduce populations, weaken adaptive capabilities, increase the incidence of inbreeding and restrict reproduction, thereby enhancing the probability of species' extinctions (Ebert et al., Reference Ebert, Haag, Kirkpatrick, Riek, Hottinger and Pajunen2002; Reed & Frankham, Reference Reed and Frankham2003). These are key dangers to the populations of the Balkan chamois Rupicapra rupicapra balcanica (Shackleton, Reference Shackleton1997), exposed to significant hunting and tourist pressure.
The decrease in the herd size of the chamois on Kasprowy Wierch is not a result of population changes observed in the Tatra Mountains because the population increased significantly between 1999–2001 and 2008–2010. The mechanism governing the decrease in observed herd sizes as a result of intensified human pressure may resemble the behaviour elicited by predator pressure (Frid & Dill, Reference Frid and Dill2002). It is likely that male chamois, which tend to form smaller herds (Jamrozy et al., Reference Jamrozy, Pęksa, Urbanik and Gąsienica-Byrcyn2007), are more tolerant than females and young of habitats that are subject to greater threats and disturbance (Childress & Lung, Reference Childress and Lung2003; Grignolio et al., Reference Grignolio, Rossi, Bassano and Apollonio2007). In disturbed areas the percentage of female chamois decreased more than that of males, and the number of young accompanying female herds dropped significantly. At the same time, the decrease in family herd size compels the individuals in the herd to raise their levels of vigilance (Roberts, Reference Roberts1996; Kluever et al., Reference Kluever, Breck, Howery, Krausman and Bergman2008).
The amount of time that ungulates devote to vigilance is a function of group size, which, apart from the social composition of the herd, may depend on other environmental factors, such as the steepness of the terrain (Manor & Saltz, Reference Manor and Saltz2003; Tadesse & Kotler, Reference Tadesse and Kotler2012) or the frequency of disturbance (Berger, Reference Berger1978; Casey et al., Reference Casey, Brown, Hardy, Barber, Fristrup, Crooks and Angeloni2012). Chamois should therefore occur in larger groups in insecure habitats. The main natural threats to chamois are the wolf Canis lupus and lynx Lynx lynx. Both predators avoid proximity to people and may follow chamois herds in remote areas. In 2008–2010 the size of the herds increased with distance to tourist infrastructure; this could potentially be a result of greater pressure from predators in areas further from the infrastructure.
Human activities in high-mountain ecosystems should consider the wild species inhabiting these areas, and information regarding the threats caused by people should be given prominent exposure in important natural areas. This is particularly important in environments that are subject to strong tourist pressure, where the numbers of tourists should be limited and controlled. In the absence of appropriate conservation tools, some populations of high-mountain species, including the Tatra chamois, may decrease or potentially become locally extinct.
Acknowledgements
Information on the number of tourists was collected by the Tatra National Park. We wish to express our gratitude to Marco Festa-Bianchet and an anonymous referee for their constructive comments. This work is dedicated to the memory of the late Jakub Mucha, our friend, who loved the mountains and their nature.
Biographical sketches
Łukasz Pęksa takes an active part in research and monitoring projects in Tatra National Park, and is interested in nature conservation and human impacts on the environment of the Tatra Mountains. Michał Ciach's area of research is animal ecology and conservation, with a particular focus on human impacts in mountain areas.