Beaver (Castor Fiber L, Castoridae) Management in Bavaria
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© Biologiezentrum Linz/Austria; download unter www.biologiezentrum.at Beaver (Castor fiber L, Castoridae) management in Bavaria VON G. SCHWAB & M. SCHMIDBAUER Abstract Zusammenfassung Beavers were exterminated in Bavaria in Biber {Castor fiber L, Castoridae)- 1867. The reintroduction, conducted by the Management in Bayern „Bund Naturschutz in Bayern e.V." between 1966 and the late seventies, was very suc- Biber wurden 1867 in Bayern ausgerot- cessful: the present beaver population in tet. Die Wiederansiedlung unter der Füh- Bavaria is estimated at more than 6.000 in- rung des „Bund Naturschutz in Bayern e.V.", dividuals, and it is still growing and expand- die zwischen 1966 und Ende der 1970er Jah- ing into its former range. re stattfand, war sehr erfolgreich. Die derzei- tige Biberpopulation in Bayern wird auf über This success was paralleled by a growing 6000 Individuen geschätzt, nimmt weiter- number of conflicts between beavers and hin zu und breitet sich auf das ursprüngliche human land users in the densely settled and Gebiet aus. intensively used Bavarian landscape. Zeitgleich mit diesem Erfolg stieg auch Beavers fed on crops, beaver dams flooded die Zahl der Konflikte zwischen Bibern und forests, pastures and basements, beavers Landnutzern in der dicht besiedelten und digged their burrows under roads, fields and intensiv genutzten bayerischen Landschaft. high water dikes, and some of them felled Biber fressen Feldfrüchte, durch ihre apple trees in gardens. During the 1980s un- Dämme werden Wälder, Viehweiden und til the early 1990s, the beaver conflicts es- Keller überstaut, sie bauen ihre Röhren un- calated, less because of the real world prob- ter Straßen und Felder, in Hochwasserdäm- lems, but more because politicians and mass men und einige fällen Apfelbäume in Gär- media abused this conflict between nature ten. conservation and land owners for personal In den 1980er Jahren bis zu Beginn der gain. 1990er Jahre eskalierten die Konflikte, es Taking a closer look at beaver-human- waren keine weltbewegenden Probleme, conflicts, we found, that almost all conflicts aber Politiker und die überwiegende Mehr- root in the overuse of landscape by man: zahl der Medien missbrauchten diesen Streit beaver conflicts happen mainly in a narrow zwischen Naturschutz und Landnutzern zur strip along the river banks. Where man has persönlichen Profilierung. left some space to the rivers, there are only Betrachtet man diese Konflikte zwi- very few conflicts with beavers. Such unused schen Biber und Landnutzern näher, kommt areas are not only important for beavers and man zu der Erkenntnis, dass die Hauptursa- other plant and animal species, but more and che in der Übernutzung der Landschaft mainly for man himself (e.g. for protection of liegt: Der Großteil der Probleme liegt in ei- water and prevention of floods). nem schmalen Uferstreifen. Ließe man die- Key words: beaver, Castor fiber, man- sen Streifen ungenutzt, wären die Konflikte agement, Bavaria auf ein Minimum reduziert. Solche unge- nutzten Bereiche wären nicht nur für den Biber und andere Tier- und Pflanzenarten Denisia 9, zugleich Kataloge der OÖ. Landesmuseen wichtig, sondern vor allem auch für den Neue Serie 2 (2003), 99-106 99 © Biologiezentrum Linz/Austria; download unter www.biologiezentrum.at Menschen selbst, z. B. für den Wasserschutz In Bavaria, where a successful beaver und zur Verhinderung von Hochwässern. reintroduction between 1966 and the late 1970s yielded an still expanding population Introduction of more than 6000 animals, these conflicts remained unsolved for many years and Beginning in 1996, 30 years after caused increasing disputes between nature beaver's reintroduction, a beaver manage- conservation organisations and agencies and ment was developed with the goal to keep land users and their associations, the top de- and promote the beaver in Bavaria by cre- mand being the complete re-removal of ating and improving acceptance for beavers from cultivated landscape. beavers and their activities. The develop- ment of the beaver management was fund- In this paper we give a short overview of ed by the European Community, program the history of beavers in Bavaria and the LEADER II, and local authorities; the im- problems they are causing and present then plementation is funded by the "Bayerische the beaver management which was devel- Naturschutzfonds" (Bavarian State founda- oped in the last years to solve the problems tion for the protection of Nature), and the and - in the long run - to use the beaver as "Bund Naturschutz in Bayern e.V." (a a flagship species for the restoration of river- NGO). side forests. The key to the future of the beavers in Bavaria are the landowners, on whose The Beaver in Bavaria: properties the beavers are living. We consult a short history these landowners in case of conflicts with beavers and assist them in applying for fund- Historic distribution and extinction ing for protective measures; we also try to Beavers were a common species in convince them to give up agriculture or Bavaria up to the 16'h century. Their distri- forestry and to lease or sell the land to state bution over almost all of Bavaria, with ex- agencies or private nature conservation or- ception of the Alps and the higher areas in ganisations. We also do public relations work low mountain regions, is documented by on a broader scale to inform the general pub- about 300 names of villages, streams or lic about beavers, its benefits for wildlife, landscapes (ZAHNER 1997). The decline of conflicts and the solutions for the future of the beaver population began locally in the the beaver within the beaver management. 17th century, expanded through the 18 cen- Another important issue is the implementa- tury and ended with the killing of the last tion of beavers and its habitats in long-term Bavarian beaver in 1867 (WEINZIERL 1973). landscape planning, as this is one of the best The reason for the extinction of the ways to reserve areas for beavers and river- beaver in Bavaria was over-hunting. They side forests from an early stage. were hunted for meat, for their valuable pelt Beavers (Castor fiber L.) are very capa- and for castoreum, which was widely used as ble of modelling the land they live in (e.g. remedy. Habitat changes, esp. the regulation DJOSHKIN & SAFONOV 1972, NOVAK 1987): of the major rivers and large bog areas had beaver dams flood and wet large areas, their only an indirect influence by allowing an burrows and dens increase the structure of easier access for hunters into the last re- river banks, and the cutting of trees creates maining beaver territories (ZAHNER 1997). openings in the riverside forests. As positive as these activities are from a nature conser- Reintroduction vation point of view, as problem causing Reintroduction of beavers in Bavaria they are, when beaver express them in a cul- began in 1966, 99 years after the last beaver tivated landscape used by man: beaver dams was killed. Until the late 1970s, the "Bund flood corn fields, machinery and people may Naturschutz in Bayern e.V.", the major na- fall into beaver burrows, beaver burrows ture conservation NGO in Bavaria released threaten functionality of dikes, the last trees about 120 beavers in several different places disappear from the rivers. (WEINZIERL & FROBEL 1998). The beavers 100 © Biologiezentrum Linz/Austria; download unter www.biologiezentrum.at .j.....:....i....^.M....i~;^.. i.....:Vvi...Ji JL.IfA....: :....: ..A \.-JSl.... •... came from wild and captive source popula- j tions in Sweden, Finland, France, Poland .1.... I j... \ i . i and the Sovjet Union (WEINZIERL 1973). i H•s < r Reintroduction was permitted by the Bava- A A(A I v/ rian Ministery for Forestry and Agriculture, iAr* A as beavers were listed as game species at this A 5 time. h \ A A AH A AAIA, In the middle of the 1980s, some I \ x•\ A n k i A beavers were trapped in the central Danube V A AjA A A/A£ area in Bavaria and relocated to the Inn U r••# Am A AT • and Isar river (SCHWAB et al. 1994). In \ A 4? A A*£A$AA northern Bavaria, beavers immigrated in the C A A AA Af A AA V i • early 1990s from a reintroduced population \A AA AA AA AA4 A of East German beavers in Hessia. (SCHWAB t } A AAA A A A A" AAA" i \ et al. 1994). i! J A A AAIL AA A A AAA A _i h. A \ A » AA A AAE A A. sA Present status of the Bavarian beaver 1AA A'A A A X A population i \ ( A-^ AA AA A A 1 X« A A A A A A A- During the first decades after reintro- t AAJ AJ A A A —i A duction, the Bavarian beaver population —• A A A A A A A A grew scientifically almost unattended. The /S£ A f A A 1 i >AA A AA A A A A / • V/ first state wide population estimate based > A A 4 A AA A on a poll and field work was conducted A / from 1988 to 1992. At this time, the popu- / M — — lation was estimated at about 800 to 1200 1 i ( A animals (SCHWAB et al. 1994). In 2002, we i A estimate the beaver population in Bavaria ij A to more than 6000 animals in 1500 h ^^ J "\ j> colonies. The beavers have reoccupied a r %, •— / —— large part of their former range (Fig. 1, £ { Regierung von Unterfranken 2001), al- i..... A though colony density is low at the borders If Fig 1. Beaver distribution in Bavaria. small drainage ditches in extensive farm of the present range. lands, they digged their burrows in the (Regierung von Unterfranken 2001) banks of sewage treatment ponds or under The Bavarian beavers have also changed roads, and they used drainage pipes under their legal status since reintroduction.