Practical aspects in the relocation of Hermit beetle Osmoderma barnabita miropopulations in Latvia

Abstract

Hermit beetle Osmoderma barnabita is a species of beetle protected in Latvia and Europe. In accordance with the data of the report to the European Commission on the situation of habitat and species protection in Latvia for 2007–2012 (Article 17 report), the population size of the Hermit beetle Osmoderma barnabita protected both in Latvia and Europe is estimated at 350–1000 localities. Specially Protected Nature Territories (hereinafter – SPNT) with Natura 2000 site status contain 71 (41 %) of population, while 103 (59 %) of population are situated outside these sites. A considerable portion of Latvia’s population inhabits parks, avenues and other plantations of residential areas, where the hollow trees are felled and removed more and more frequently. The objective of the article is to publish the experience of the research on dead trees inhabited by Osmoderma barnabita accumulated to date, methodological aspects of population relocation, as well as to provide recommendations for further research and micropopulation relocation work. The research of the trunks of broken or felled trees by dividing them into shorter spans, sieving the rotten wood, describing the structure of the hollows and counting the detected specimens of Osmoderma barnabita, was used as the main research method. Varying quantities of dead wood and numbers of Osmoderma barnabita (1–83 specimens) and Liocola lugubris (6–55 specimens) have been detected in the five examined trees. In two cases it was detected that in the time period from the felling of the tree until examination (20–40 days) the number of larvae present in the wood was reduced. The hypothesis was proposed that the internal surface area of the hollow of the tree is a significant factor that determines the number of Osmoderma barnabita specimens in the hollow.

European Commission. 2013. Reporting under Article 17 of the Habitats Directive (period 2007–2012). Introduction to assessment of conservation status of habitats and species of Community interest. http://bd.eionet.europa.eu/activities/Reporting/Article_17 (Accessed 31.01.2018.)