KORA Bericht Dispersal 100418.Indd
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KORA Bericht Nr. 50 April 2010 ISSN 1422-5123 Expansion of lynx in the Alps Koordinierte Forschungsprojekte zur Erhaltung und zum Management der Raubtiere in der Schweiz. Coordinated research projects for the conservation and management of carnivores in Switzerland. Projets de recherches coordonnés pour la conservation et la gestion des carnivores en Suisse. KORA, Thunstrasse 31, CH-3074 Muri. Tel +41-31-951 70 40, Fax +41-31-951 90 40, Email: [email protected], http://www.kora.ch 2 KORA Bericht Nr 50 KORA Bericht Nr. 50 Expansion of lynx in the Alps Autoren Anja Molinari-Jobin, Ivan Kos, Eric Marboutin, Auteurs Paolo Molinari, Sybille Wölfl, Michael Fasel, Authors Christine Breitenmoser, Christian Fuxjäger, Thomas Huber, Iztok Koren, Krzysztof Schmidt, Josip Kusak, Harri Valdmann, Fridolin Zimmer- mann, Manfred Wölfl, Urs Breitenmoser Bearbeitung Anja Molinari-Jobin (Layout) Adaptation Editorial Impressum KORA Thunstrasse 31 3074 Muri Tel.: 0031-31-951-7040 E-Mail: [email protected] Bavarian Environment Agency Bayerisches Landesamt für Umwelt Bürgermeister-Ulrich-Straße 160 86179 Augsburg Tel.: 0049-821-9071-0 E-Mail: [email protected] Bezugsquelle Als Pdf: http://www.kora.ch Source Source Titelbild Luciano Ramires Page de titre Front cover picture Anzahl Seiten/Pages: 17 ISSN 1422-5123 © KORA April 2010 April 2010 3 Expansion of lynx in the Alps Anja Molinari-Jobin, Ivan Kos, Eric Marboutin, Paolo Molinari, Sybille Wölfl, Michael Fasel, Christine Breitenmoser, Christian Fuxjäger, Thomas Huber, Iztok Koren, Krzysztof Schmidt, Josip Kusak, Harri Valdmann, Fridolin Zimmermann, Manfred Wölfl, Urs Breitenmoser 4 KORA Bericht Nr 50 Acknowledgements This review was conducted by the SCALP (Status and Conservation of the Alpine Lynx Population) expert group, and three lynx experts have contributed their unpublished data. This report was financed by the Bavarian State Agen- cy of Environment, while SCALP in general receives funding by the MAVA foundation. We thank Andreas Ryser for providing data and expertise about the translocation project. April 2010 5 Expansion of lynx in the Alps Index Abstract..........................................................................................................................................................6 Introduction....................................................................................................................................................7 Concepts and definitions................................................................................................................................7 Metapopulation......................................................................................................................................7 Population spread/colonization..............................................................................................................8 Land tenure system................................................................................................................................9 Dispersal..............................................................................................................................................10 Methods........................................................................................................................................................10 Present status and trend.......................................................................................................................10 Dispersal..............................................................................................................................................10 Survival...............................................................................................................................................11 Results..........................................................................................................................................................11 Present status and trend.......................................................................................................................11 Dispersal..............................................................................................................................................12 Survival...............................................................................................................................................13 Discussion....................................................................................................................................................13 Next steps.................................................................................................................................................... 15 References....................................................................................................................................................15 6 KORA Bericht Nr 50 Abstract The Bavarian State Agency of Envi- the north-eastern Swiss subpopula- In a next step it would be impor- ronment commissioned the SCALP tion is the closest potential source tant to analyze lynx movements in expert group to review existing data to the Bavarian Alps where regular respect to barriers to evaluate the on lynx dispersal and to discuss the reproduction is reported from. With permeability of the barriers created likelihood of a natural recoloniza- a distance of ca. 70 km the Bavar- by highways, as it is important to tion of the Bavarian Alps by lynx. ian Alps are within dispersal range know how often lynx leave their Dispersal data was available from 60 of the north-eastern Swiss subpopu- source habitat patch and “manage” individual lynx. Dispersal distances lation. Yet, the probability that a to cross such barriers, how they in- ranged from remaining philopatric lynx will reach the Bavarian Alps teract and communicate across such to more than 400 km. However, 68% highly depends on the availability barriers, and how they establish in- of documented dispersal distances of suitable habitat and especially its dividual home ranges in new areas were less than 50 km. fragmentation. Since lynx dispersing to predict how the species colonizes In the light of a complete recoloniza- from north-eastern Switzerland to a new patch. And finally, to predict tion of the Alps (and in particular the the Bavarian Alps have to cross two the future and spread of the Alpine Bavarian Alps), three factors need to highways, it is probable that most of lynx occurrences, we need to model be considered: (1) an analysis of the them will take another dispersal di- the population viability of the pres- closest existing source population, rection. ent lynx occurrences in the Alps by (2) the dispersal capability of lynx, Since the probability that even a means of a spatially explicit demo- their survival probability and asso- single lynx reaches the Bavarian graphic model. Based on the repro- ciated mortality factors, and (3) the Alps is low, a natural recolonization duction and survival data from lynx probability of the establishment of a of this area within the next decades, in the Alps we need to evaluate the population nucleus given successful followed by the successful settle- probability of persistence (or extinc- dispersal or the enlargement of an ment of a viable population nucleus, tion) of existing occurrences. This existing occurrence, respectively. seems very unlikely. The further an would allow us to include different The Alpine lynx population present- animal disperses from its core range management scenarios into the mod- ly consists of 5 more or less isolated the less likely it will find a mate later eling. These kinds of analyses would subpopulations or occurrences. Dur- on. A population viability analysis produce the basis for future conser- ing the past 10 years the occupied has revealed that from a demograph- vation and management efforts. area of lynx in all the Alps increased ic viewpoint at least 10 females and by ca. 6000 km2 or 50% based on a 5 males are required for a start that raster grid of 10x10 km. Presently, will develop into a viable population. April 2010 7 Introduction The Alpine lynx metapopulation management strategies linked to the to further approach the issue of went extinct during the 19th century. status of brown bear, wolf and lynx “natural recolonization vs. rein- In the 1970s and 1980s, lynx from the (StMUG 2007a, b; 2008). One issue troduction” of lynx in the Alps. Slovak Carpathians were released in controversially discussed centered the Swiss, Austrian and Italian Alps on the presumed low expansion of and in the adjacent Jura Mountains the lynx in the Alps and in particular Concepts and definitions (Switzerland), Vosges (France), around the questions: the Dinaric range (southern Slove- (1) Whether lynx are per se not able Metapopulation: Linnell et al. (2008) nia) and Bavarian-Bohemian Forest to recolonize the Bavarian Alps from recently provided a review of the bio- (Czech Republic). These reintroduc- Switzerland and Slovenia due to the logical and demographic processes tion projects resulted in several local distances from the source populations that underlie the classical concept of populations and isolated occurrenc- and/or the lack of suitable corridors, a population. The basic idea refers es (von Arx et al. 2004, Capt 2007, (2) or do not recolonize the central to a group of individuals that live Molinari-Jobin et al. 2010, Wölfl et Alps because of high mortality in the in the same area and can potentially al. 2001). While lynx populations in two source populations