Ancient Tree Forum

by Thomas Ranius email		Sweden - home

This Trichiinae beetle with an agreeable scent of perfume ('Russian leather') is regarded as endangered throughout its all distribution area. Probably their largest populations of the world are to be found in the south east parts of Sweden!	Osmoderma eremita is a threatened beetle associated with old, hollow trees. In Sweden, oak trees situated in pasture woodlands are the most important habitat. I have studied how O. eremita is affected by habitat fragmentation by comparing its incidence in small in comparison with large stands with hollow oaks. I have also assessed the population size and its fluctuations between years. Together with Jonas Hedin - website Lund University, I have studied the dispersal of the species. We have found that O. eremita occurs more frequently in oaks situated in a large stand in comparison to a similar oak situated individually or in a small stands. The population size is remarkably constant between years and the fluctuations occur asynchronously between trees. Most individuals remain in the same tree throughout their entire life-time, and only 15% move to other trees. This suggest that O. eremita populations may be described as metapopulations, with each tree sustaining a local population, and at a stand level a metapopulation is formed. In the future I plan to predict the extinction risk of O. eremita populations in landscapes differing in habitat density and management strategy. Then I will use different kinds of computer simulation models.

Research on the beetle Osmoderma eremita