Abstract
Many butterfly target species are associated with early successional stages of grasslands. The Blue-spot Hairstreak, Satyrium spini (Denis & Schiffermuller, 1775), is a target species of grasslands. However, it feeds on Common Buckthorn (Rhamnus cathartica), which is associated with late successional stages of grasslands. If S. spini would also be restricted to late seral stages, there might be a management dilemma due to the contrasting requirements of S. spini and other target species. The aim of this study was to determine the oviposition preference of S. spini in calcareous grasslands, and to give management recommendations to promote this species. Therefore, we studied the oviposition microhabitats of S. spini at three representative patches of the Diemel Valley (Central Germany) by comparing environmental conditions on occupied and control host plants. In total we surveyed 1,889 host plants. Altogether we found 148 batches of S.spini on them containing 396 eggs. Most of the eggs were on plants that grew under the warmest conditions. Females preferred to lay eggs on small (< 1.3 m) shrubs of Rh. cathartica fully exposed to the sun growing on steep south- and west-facing slopes. This butterfly showed no difference in its preference for bushes growing in hedges or solitarily. About 80% of the batches of eggs were laid on the upper surface of a twig fork close to the surface of the ground (< 1 m). Our study showed that S. spini is a species characteristic of mid-successional stages of calcareous grasslands. The survival of suitable habitats for S. spini depends on regular management. To achieve this we recommend traditional rough grazing with sheep and goats, which creates open grasslands with small Rhamnus plants. In addition, the shrubs in tall hedges bordering calcareous grasslands should be subjected to cutting on a rotating basis.
Highlights
Calcareous grasslands are one of the most species-rich habitats in Europe, harbouring many threatened plant and animal species (Willems, 1990; Steffan-Dewenter & Tscharntke, 2000)
The Blue-spot Hairstreak, Satyrium spini (Denis & Schiffermüller, 1775), is a target species of grasslands. It feeds on Common Buckthorn (Rhamnus cathartica), which is associated with late successional stages of grasslands
Our study showed that S. spini is a species characteristic of mid-successional stages of calcareous grasslands
Summary
Calcareous grasslands are one of the most species-rich habitats in Europe, harbouring many threatened plant and animal species (Willems, 1990; Steffan-Dewenter & Tscharntke, 2000) As it is a semi-natural habitat it needs to be managed. Intensification of land use, abandonment and afforestation are responsible for the marked reduction in the area and quality of semi-natural grasslands over the last few decades (Van Dijk, 1991; Kahmen et al, 2002; WallisDeVries et al, 2002). Because of their value as biodiversity hotspots in our landscapes and strongly endangered status they are protected under the EU Habitats Directive (Ssymank et al, 1998). Butterflies are ranked among the most threatened groups of animals (Thomas et al, 2004; Van Swaay et al, 2006)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.