The ongoing climate warming may result in more frequent and more intensive fire events in the Central Alps. Because studies on the long-term fire history of the Central Alps suggest that forest fires were naturally more frequent, questions on the ecological resilience of these mountain forests after fires arise. On an 300 ha forest fire patch along an altitudinal gradient the re-colonisation has been observed annually after the fire event in August 2003. Re-vegetation has been assessed on a systematic sample (n=154) and on a stratified sample (n=40). On the latter sample, the original forest vegetation was assessed in 1996. Invertebrates were sampled weekly during the summer seasons 2004 and 2005 (1 and 2 years after the fire) on 18 trap sites along three transects at different altitudes. Trap sites were grouped into the three habitat types 'intact forest', 'burnt forest' and 'transition zone'.
Two years after the fire, following results are at hand: For a wide area, the vegetation was literally missing in 2004, though returned successively in 2005. Correspondingly the trees regenerated only locally in 2004. The speed of re-colonisation in terms of numbers of plant species strongly depended on the scale in consideration. On plots of 200 m² average species richness of the pre-fire vegetation and the post-fire vegetation in 2005 were equal, whereas at the scale of 500 m², the post-fire vegetation was significantly richer. Fire severity, as indicated by the thickness of the ash layer in 2004, correlated negatively with both vegetation cover and number of plant species in 2004. About 50 % of the collected invertebrate individuals were pollinators and 29 % were predators. Highest individual numbers were counted in the transition zone. The started studies will be continued in the next years in order to monitor the post-fire recovery and to seek for altitude-related differences in the fire adaptability of these forest-ecosystems.