Monitoring of the saproxylic beetle Morimus asper funereus Mulsant, 1862 (Coleoptera: Cerambycidae) in Măcin Mountains National Park, Romania

Abstract

During 2014 and 2015, the species Morimus asper funereus Mulsant, 1862 was monitorised in the Măcin Mountains National Park, Romania using the visual transect method. The studied was focused on two topics: to determine the numerical abundance of Morimus asper funereus populations and to identify the environmental variables which influenced them. Ten abiotic factors were analysed: altitude (A), exposition (Ex.), slope (S.a), forest coverage (F.c.), air temperature (A.t.), soil temperature (S.t.), air relative humidity (A.h.), cloud-cover (Nb.), wind speed (W.s.) and wind direction (W.d.). During the study period, 112 individuals were identified. The most favourable habitats for this species were Moesian silver lime woods (91Z0) and Pannonian-Balkanic Turkey oak – sessile oak forests (91M0). The main environmental variables that influenced the beetle population dynamics were the forest coverage and wind direction. Taking into account these two parameters, we concluded that Morimus asper funereus preferred semi-shaded and semi-open habitats, characteristic of mature, old, deciduous forests within the Măcin Mountains National Park. In order to protect this species, special attention must be given to the forest management measures, e.g. protection of fallen trees, abundant coarse woody debris and a dense canopy.