Abstract

Saproxylic beetles are a key component of forest biodiversity and important indicators of forest naturalness, dead-wood continuity and habitat quality. Floodplain forests with old oak stands are among the most species-rich forest ecosystems in Europe, yet data on saproxylic beetle assemblages from such habitats remain scarce in south-eastern Europe. In this study, saproxylic beetles were investigated in three floodplain forest communities within Kopački rit Nature Park (eastern Croatia) using flight-intercept, pitfall and aerial attractant traps during the 2014 vegetation season. A total of 64 saproxylic beetle species from 14 families were recorded. Species richness and abundance were highest in oak-hornbeam forests, intermediate in poplar forests and lowest in willow-dominated stands, which nevertheless supported structurally distinct assemblages. Diversity indices and ordination analyses revealed a strong gradient in community structure from oak-dominated to willow-dominated floodplain forests. Flight-intercept traps were the most efficient sampling method, whereas other trap types provided complementary information on habitat-specific taxa. Several species listed on the European Red List of Saproxylic Beetles were recorded, including the Natura 2000 species Lucanus cervus and Cucujus cinnaberinus. Of particular importance was the detection of Rhysodes sulcatus, which triggered targeted faunistic surveys that confirmed its presence at additional Croatian localities and led to its formal inclusion in the Croatian Natura 2000 species list. Although the data were collected in 2014, they provide a valuable baseline for assessing saproxylic beetle diversity in natural floodplain forests and for the development of national Natura 2000 monitoring programmes. The results highlight the exceptional conservation value of Kopački rit as one of the best-preserved floodplain forest systems in the Continental biogeographical region.

Keywords

Coleoptera, biodiversity, conservation, sampling methods, oak, threatened species, dead wood, eastern Croatia

Fulltext

Saproxylic beetle assemblages in floodplain forests of Kopački rit Nature Park (Croatia): A baseline for Natura 2000 monitoring