engleski

Distribution, habitat and conservation status of the endangered water beetle Graphoderus bilineatus in Croatia

The dytiscid water beetle Graphoderus bilineatus is one of few beetles protected by both EU Habitats Directive and Bern Convention and listed as Vulnerable in the IUCN Red List. Although widely spread across Europe, in most countries its overall conservation status is 'Unfavourable-Bad'. So far, only two historical records were known in Croatia (1907, 1943). During 2010 and 2011 we investigated the distribution and habitat of the species in order to designate NATURA 2000 sites and asses the conservation status in Croatia. In total, 83 sampling sites were selected and sampling was performed by pond-net and baited bottle traps. Additionally, we created a potential distribution model. We discovered new abundant populations of G. bilineatus (total of 69 specimens) at 20 sites restricted mainly to protected natural wetlands along the Danube, Drava and Sava rivers, which we proposed as NATURA 2000 sites for this species. 95 % of presence sites were within protected areas. The main habitats are flood-meadows, ox-bows and canals with stagnant waters and aquatic vegetation of medium density. Our first results indicate that G. bilineatus may have a favourable conservation status in Croatia. Its habitats are of suitable quality and sufficiently covered by existing protected areas.

Graphoderus bilineatus; Conservation; Habitat; Distribution; Croatia

nije evidentirano