Berthelsen, J.P. & Madsen, A.B. 2006. 32 pp.
After the release of beavers in October 1999 in Klosterheden State Forest District (KLS), the natural conditions in the beaver activity areas were investigated and surveyed. The National Environmental Research Institute (NERI) undertook the technical coordination and reporting with regard to the monitoring of beavers during the period 1999-2003. In 2004 and 2005, fieldwork and monitoring were carried out by KLS in cooperation with NERI. Based on data from the KLS monitoring and population counts, NERI has prepared the annual report for the beaver monitoring for 2005. This report provides an update of the status of population distribution, growth and mortality as at the end of 2005.
At the beginning of April 2005, a total count was carried out in all the beaver territories, involving a large number of volunteers. Observations made by the forester, landowners and public visitors supplemented the population estimates and the mapping of the dispersal to new localities. Along the more inaccessible stretches of watercourse, canoes were used to observe and survey beaver activity. On the basis of the actual number of observed individuals, the total beaver population in the breeding season of 2005 was estimated at a minimum of 76 individuals, including 15 juveniles. One dead beaver was registered in 2005. A total number of 17 beaver territories was registered, one less than in 2004.
In general, the location of beaver territories almost represented a status quo compared with 2004, but some home ranges within these territories have changed in several cases. In locations where beavers have settled over a number of years, the core areas of beaver activity have changed within the territory. In areas inhabited by beavers over four to five years, beaver dams and lakes have been built and the local natural conditions have changed substantially. The change, however, is less pronounced around lakes than it is along watercourses.
In 1999-2003 all registered lodges were supervised and all landowners with beavers on their property were contacted. KLS continued this practice in 2004 and 2005. When problems arose, the staff of KLS, in consultation with the owners, undertook some form of remedial measures. In total, more incidents and complaints were registered in 2005, but this should be seen in light of the general increase in the population of beavers and dispersal into new habitats.
In 2005 there was still large public interest in visiting the beaver sites. In total, staff from KLS arranged 72 excursions and guided tours with 2,064 participants. Some guided tours have been arranged for school children, managed by rangers at the district. During the course of last year a new concept for promoting nature study was developed using a bus that has been converted into a rolling laboratory with a wide range of equipment. Moreover, many volunteers are involved in the annual beaver counts. Besides generating data for monitoring the beaver population, these surveys play an important role in disseminating the reintroduction project to the general public.
Full report in pdf-format (1,173 kB).
