Forest as a habitat of saproxylic beetles on Natura 2000 sites in Slovenia

Abstract

Natura 2000 sites represent almost 36% of the Slovenian area; a large part of the area is overgrown with forests (nearly 70%), a big share is without vegetation, an important part is grassland. The areas of Natura 2000 under the Wild Birds Directive include 26 SPA (Special Protection Areas) sites with an area of 461 819 ha and under the Habitat Directive 260 pSCI (potential Sites of Community Interest) sites with an area of 639,735 ha. Slovenia proposed ten forest habitat types and they include nearly 265,485 ha of forests or 21.62% of our forest areas. The number of species from the list of plant and animal species from Appendix II of the Habitat Directive amounts to 138 species, there are 16 species of beetles: 13 more or less forest dependent species (Bolbelasmus unicornis, Buprestis splendens, Carabus variolosus, Cerambyx cerdo, Cucujus cinnaberinus, Limoniscus violaceus, Lucanus cervus, Morimus funereus, Osmoderma eremita, Phryganophilus ruficollis, Rosalia alpina, Rhysodes sulcatus and Stephanopachys substriatus) and three not forest dependent species (Carabus menetriesi pacholei, Graphoderus bilineatus, Leptodirus hochenwartii). More than 80% of all Natura 2000 beetles were found to be forest dependent. Four of them are EU priority species (Carabus menetriesi pacholei, Osmoderma eremita, Phryganophilus ruficollis, Rosalia alpina), they represent 25% of all Natura 2000 beetles. We present the actual wide range for six beetles (C. cerdo, C. cinnaberinus, L. cervus, M. funereus, O. eremita and R. alpina) on the basis of recently accessible data. A majority of location records (145 records) are located in 21 SPA areas, 99 location records are in 32 pSCI areas. Even though a majority of locations lie in SPA areas, pSCI are quite a frequent habitat for some of the beetles, e.g. M. funereus and R. alpina. 21 out of 26 SPA are important for 6 beetles included into the analysis. There are also 32 of 260 potential pSCI that have locations of some beetles included into analysis. L. cervus, M. funereus, and R. alpina appear more often in pSCI than in SPA areas. We present the stand requirement of selected forest beetles in particular forest plant communities and lands which they actually inhabit.