Habitat availability is not limiting the distribution of the Bohemian–Bavarian lynx Lynx lynx population N ORA M AGG,JÖRG M ÜLLER,CHRISTOPH H EIBL,KLAUS H ACKLÄNDER S YBILLE W ÖLFL,MANFRED W ÖLFL,LUDÊK B UFKA J AROSLAV Č ERVENÝ and M ARCO H EURICH Abstract A population of Eurasian lynx Lynx lynx was es- c. (–) resident lynx. We assessed connectivity via tablished by reintroductions in the Bohemian Forest least-cost paths and found that all suitable patches could Ecosystem in the s and s. The most recent informa- be reached by the lynx. A comparison with the current dis- tion on the population status indicates that the distribution tribution of lynx, however, confirms that a significant pro- has stagnated since the late s, for unknown reasons. We portion of suitable habitat is not occupied, which indicates assessed the availability of suitable habitat along the that the distribution is limited by factors other than habitat, Austrian–German–Czech border, and hypothesized that with illegal killing being the most likely cause. Our study the Bohemian–Bavarian lynx population is not in equilib- provides crucial information for the development of a con- rium with habitat suitability. Based on global positioning servation strategy and regional planning for the Bohemian– system data from radio-collared lynx, we used a max- Bavarian lynx population. imum entropy approach to model suitable habitat. Keywords Habitat connectivity, home range, large carni- Variables reflecting anthropogenic influence contributed vore conservation, least-cost paths, Lynx lynx, radio track- most to the model and were negatively associated with the ing, species distribution modelling occurrence of lynx. We evaluated the model prediction using independent records of lynx from monitoring in To view supplementary material for this article, please visit Bavaria, Germany. Using our habitat approach we estimated http://dx.doi.org/./S the area of potential habitat, based on a mean annual home range of km for males and km for females. Our re- sults indicated there were , km of suitable habitat, dis- tributed among patches, for a potential population of Introduction fter decades of persecution and extermination of large Acarnivores in Europe, populations have started to re- ‡ † NORA MAGG* (Corresponding author) and JÖRG MÜLLER Bavarian Forest cover (Chapron et al., ). Management policy has im- National Park, Freyunger Str. 2, 94481 Grafenau, Germany E-mail [email protected] proved considerably and large carnivores are protected by CHRISTOPH HEIBL Department of Ecology and Ecosystem Management, law in most European countries (Molinari-Jobin et al., Technische Universität München, Freising, Germany ). They are recolonizing their former ranges both natur- KLAUS HACKLÄNDER Department of Integrative Biology and Biodiversity ally and through reintroduction (Linnell et al., ); how- Research, Institute of Wildlife Biology and Game Management, University of ever, they are confronted with a human-dominated Natural Resources and Life Sciences, Vienna, Austria landscape, where their habitats are diminished and frag- SYBILLE WÖLFL Lynx Project Bavaria, Lam, Germany mented as a result of direct destruction and the development MANFRED WÖLFL Bavarian Environmental Agency, Hof/Saale, Germany of roads and railways (Fischer & Lindenmayer, ). With LUDÊK BUFKA§ Šumava National Park, Kašperské Hory, Czech Republic the reduction in habitat, wildlife populations become smal- JAROSLAV ČERVENÝ Faculty of Forestry and Wood Sciences, Czech University of ler and more isolated, both of which increase the risk of local Life Sciences Prague, Czech Republic extinction. Large carnivores are particularly vulnerable to MARCO HEURICH** Bavarian Forest National Park, Grafenau, Germany local extinction in fragmented environments because they *Also at: Department of Integrative Biology and Biodiversity Research, Institute require large contiguous spaces, and their populations are of Wildlife Biology and Game Management, University of Natural Resources low in density (Ripple et al., ). and Life Sciences, Vienna, Austria †Also at: Department of Ecology and Ecosystem Management, Technische For the Eurasian lynx Lynx lynx, stagnation and declines Universität München, Freising, Germany of reintroduced and formerly increasing populations have §Also at: Faculty of Forestry and Wood Sciences, Czech University of Life – Sciences Prague, Czech Republic been reported (e.g. the Vosges Palatinian population in **Also at: Chair of Wildlife Ecology and Management, University of Freiburg, France; the Dinaric population in Slovenia, Croatia, Bosnia Faculty of Environment and Natural Resources, Freiburg, Germany – ‡ and Herzegovina; the Bohemian Bavarian population along Current address: Forest Research Institute of Baden-Württemberg, Freiburg, – – Germany the Austrian German Czech border; Kaczensky et al., Received October . Revision requested October . ). The latter population originated from lynx captured Accepted March . First published online August . in the Carpathian Mountains and reintroduced to the Oryx, 2016, 50(4), 742–752 © 2015 Fauna & Flora International doi:10.1017/S0030605315000411 Downloaded from https://www.cambridge.org/core. IP address: 170.106.35.234, on 29 Sep 2021 at 23:20:00, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https://doi.org/10.1017/S0030605315000411 Distribution of Eurasian lynx population 743 Bohemian Forest in the s and s (Wölfl et al., ). suitable habitat and of lynx, and estimated a potential popu- The population resides in the Bohemian Forest Ecosystem, lation, considering its entire transnational range. in which the Bavarian Forest National Park and the We developed a habitat suitability model with a max- Šumava National Park are embedded. Initially data indicated imum entropy approach for the Bohemian–Bavarian lynx an increase in numbers and distribution but at the end of population, based on GPS telemetry data for individuals the s population increase stagnated, and in the Czech in the region; considered spatial requirements of lynx, using part of the Bohemian Forest the number of individuals de- estimates of annual home range; assessed the size and con- creased (Wölfl et al., ). The latest status report on the nectivity of suitable habitat patches; estimated a potential population also presumes stagnation in population size population size for the area along the border of Germany, and range in Germany and Austria. It is estimated the the Czech Republic and Austria; and compared our results Bohemian–Bavarian population comprises – indivi- with regional occurrence of lynx according to the latest sta- duals (Kaczensky et al., ). tus report (Kaczensky et al., ). We used the Bohemian The reason for the stagnation of this population is of con- Forest Ecosystem, with its characteristic Central European cern for lynx conservation in Central Europe because of the lynx population and low mountain range habitat, as a population’s central geographical location and thus its model area. Our objective was to provide wildlife managers potential to act as a link between other small and isolated and administrators involved in the monitoring and manage- populations. Isolation of a small population may result in ment of populations of large carnivores in Europe with a reduced genetic variability, lower reproductive success and state-of-the-art tool to compile information about local increased risk of extinction (Schmidt, ). Human- habitat suitability and carrying capacity for the conservation induced mortality may have an even greater impact than of a population that, as we hypothesize, is not realizing its low reproductive success (Linnell et al., ), particularly potential distribution. mortality caused by road traffic or illegal killing (Andrén et al., ; Molinari-Jobin et al., ; Müller et al., ). Habitat availability and connectivity may influence popula- Study area tion dynamics and thus may be the factor limiting the dis- The Bohemian Forest Ecosystem, Europe’s largest region of tribution of the Bohemian–Bavarian lynx. strictly protected forest, comprises a forested mountain Information on the spatial distribution, size and connect- range along the German–Czech border and includes the ivity of suitable habitat patches is a prerequisite when com- Bavarian Forest National Park ( km ) on the German paring actual and potential lynx distribution to maximize side of the border and the Šumava National Park ( the success of population conservation. Models based on a km ) on the Czech side (Fig. a). Human population dens- geographical information system provide an effective means ities are comparably low: , inhabitants per km in the of gathering information about spatial distribution and ex- National Parks and c. per km in nearby regions. Mean panse of potential habitat. Previous analyses of lynx habitat annual temperature is .°C in montane and .°C in sub- have highlighted the importance of forests, and the negative alpine elevation zones. Snow cover persists for – association of lynx presence with habitat fragmentation, days, depending on altitude. GPS data from radio-collared human settlements and areas of intensive land use lynx were collected in an area of , km within the (Niedziałkowska et al., ; Breitenmoser-Würsten et al., Bohemian Forest. This area, defined by the % minimum ; Basille et al., ). In previous models of lynx habitat convex polygon (MCP) of all lynx localizations, served as in Germany habitat suitability was