Research team:
Coordinator
Researcher´s:
Ing. Hana Šípková, Ph.D.
Mgr. Pavel Jakubec, Ph.D.
Prevention of ecosystem fragmentation in the Czech Republic: effect on necrophagous beetles (ACTIVITY 10)
The goal of ACTIVITY 10 is to gather data about changes in distribution of selected species, mostly burying beetles (genus Nicrophorus) and other species of necrophagous beetles (Coleoptera: Silphidae and Leiodidae). The outcome of ACTIVITY 10 is an analysis of biotope requirements of necrophagous beetles at selected habitats.
Research state:
The means how beetles cope with environment and its changes caused by humans, landscape fragmentation included, are stirring a lot of questions. The main reason for this interest are consequent changes in biodiversity, which could have negative effect on humanity itself. These effects could be not only of aesthetic nature, but also economical, because insect is providing a number of ecosystem services. In case of studied necrophagous beetles is important how they are affecting decomposition of organic matter and its cycle through the ecosystem.
Number of necrophagous beetles of open-landscape are considered to be rare and endangered in our nature. The goal of this project was to analyze historical and current distribution of beetles from families Silphidae and Leiodidae in the Czech Republic. Results of this analysis were used for suggestion of management measures, which should stabilize and support the population of necrophagous beetles of open-landscape.
For the analysis of distribution we used data from three sources: data from amateur and professional entomologist from Czech Entomological Society, data from revisited vouchers in various museums and the last part was collected in the field by baited pitfall traps. Resulting database encompass distribution of necrophagous beetles from beginning of 19. century till today. We used artificial intelligence algorithm MaxEnt to analyze the potential distribution. As input variables we used occurrence data and various environmental factors (temperature, precipitation, seasonality etc.). The output of the analysis was the occurrence probability map for each species in the studied area (Czech Republic). We further reclassified the map into binomial form by using Maximum training specificity and sensitivity index to allow easier and intuitive interpretation of the results.
Subsample of the animals from field collection was captured alive and they were used for the breeding of the next generation. We were interested especially in the duration of the development, because this phase is critical for the stability of population and precise timing of the management measures can be the most cost effective.
Based on 958 records we were able to analyze occurrence of three species of carrion beetles Nicrophorus antennatus, N. germanicus and N. sepultor. N. antennatus is very discriminating species and its occurrence is limited to warmest lowlands of the Czech Republic (e.g., Česká tabule, Hornomoravský úval and Dolnomoravský úval). N. germanicus is very similar in its demands, but it also occurs in the southern Bohemia. The most widespread species is N. sepultor, which is considered as least concerned of them. Its occurrence is limited only by mountain regions (e.g., Krkonoše, Šumava and Jeseníky Mts.).
All regions were these beetles can occur are used for intensive farming, which could be a major thread, especially if the non-selective pesticides are used.
We summarized the most important factors for population stability of studied species and propose management measures how to improve the current state.
- Use of non-selective pesticides in agricultural ecosystems can negatively affect the abundance of endangered sexton beetles, especially if they are applied during the breeding season (May – July). We recommend to use selective insecticides or biological and mechanical ways of plant protection at regions with confirmed occurrence of focal species.
- Use of deep tillage can negatively affect overwintering of endangered sexton beetles, therefore we propose to limit the usage of this tillage type at regions with confirmed occurrence of focal species.
- Country lanes without continuous shrub layer could serve as refugium for endangered sexton beetles. Protection, management and creation of new country lanes could help to improve population stability and colonization of new regions by beetles.
- Forests are unsuitable for colonization by endangered sexton beetles, which are without exception, open-landscape specialists. Restrict afforestation and block the succession of meadows and pastures, in regions with confirmed occurrence of focal species, could increase stability of their populations.
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