DIGITALNA ARHIVA ŠUMARSKOG LISTA
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| ŠUMARSKI LIST 11-12/2013 str. 34 <-- 34 --> PDF |
C. canadensis presence in the recently expanding beaver population (e.g. Halley & Rosell 2002; Kautenburger & Sander 2008). It therefore remains ambiguous, which of the originally released animals account for the successful resettlement. Although based only on seven individual samples, a recent study using Randomly Amplified Polymorphic DNA (RAPD) variation rejected the existence of C. canadensis in Austria, but also indicated comparatively high heterogeneity with some genetically remarkably distinct individual samples (Kautenburger & Sander 2008). In 2011 the total population size of beavers in the province Lower Austria was estimated to be about 3300 individuals (Parz-Gollner & Hölzler 2012). As a consequence of the increasing density as well as the ongoing beaver spread resulting in new settlements over the recent years, increasing conflicts with human land use have led to the implementation of a beaver management in Lower Austria. This federal state-wide beaver management basically follows a stepwise action plan, including prevention and repellent measures. Since the winter 2006/07 derogations given by the respective state administration authorities allow also trapping and killing of beavers under controlled conditions at locally restricted sites. Weight, sex, and morphometric data as well as organic material for DNA analysis were collected from all beavers killed so far under the stepwise action plan and stored deep-frozen for further research. Here, we present first genetic data on parts of these tissue sampling. By mtDNA sequence data analysis of the non-coding control region (D-loop; cf. Sbisà et al. 1997) we tried to answer the following questions: 1) Can the occurrence of C. canadensis within the current Lower Austrian beaver population be ruled out? 2) Can we identify different intraspecific lineages of the beaver often treated on the subspecific level representing both, the Western and the Eastern European C. fiber group? 3) Are there signs of hybridisation among intraspecific lineages of C. fiber? Material and Methods Materijal i metode Sample collection – Prikupljanje uzoraka Tissue and hair samples were collected during the years 2007 and 2011 based on the stepwise management plan as described above. In addition to the trapped animals (in some cases several family members per site) also road kill victims were included in our analysis. We selected individual tissue samples (i.e. muscle tissue) from different years covering most of the present distribution range of beavers in Lower Austria. Within areas of higher population density, causing more human land use conflicts in the cultural landscape area, also more individuals were trapped at specific sites and subsequently analysed. Altogether our data |