Landscape effects on butterfly assemblages in an agricultural region

Abstract

We examined the butterfly fauna at 62 sites in southeastern Sweden within a region exhibiting high variation in the landscape surrounding the studied grasslands. The landscape varied from an intensively-managed agricultural landscape with a large amount of open fields to a landscape with a high amount of deciduous forest/seminatural grassland. We made 12 179 observations of 57 species of butterflies. The amount of neighbouring deciduous forest/semi-natural grassland, with /25% tree and bush cover, was the most important environmental factor explaining the variation in the butterfly assemblages. Landscape analyses at three different spatial scales showed that the variation in butterfly assemblages could be explained only at the largest scale (radius 5000 m) and not at the smaller ones (radii 500 and 2000 m). Logistic regressions were used to predict presence/absence of butterfly species. Our study indicated that there may be critical thresholds for the amount of habitat at the landscape scale for several butterfly species as well as for species richness. For Melitaea athalia , there was a sharp increase in occupancy probability between 3 and 10% deciduous forests/semi-natural grasslands at the 5000-m scale. For 12 other species, the value for 50% probability of occurrence varied between 2 and 12% deciduous forest/ semi-natural grassland. Species which had high occupancy probabilities in landscapes with a low amount of surrounding deciduous forests/semi-natural grasslands were significantly more mobile than others. Our study highlights the importance of applying a landscape perspective in conservation management, and that single-patch management might fail in maintaining a diverse butterfly assemblage.

Moths and management of a grassland reserve: regular mowing and temporary abandonment support different species

“…Some studies targeted entire landscapes, comparing management impacts on insects over large scales (Bergman et al 2004;Wickramasinghe et al 2004). They typically relied on a few model groups, such as butterflies (Öckinger & Smith 2006;Rundlöf et al 2008), or bumblebees (Haaland & Gyllin 2010), although multi-taxa comparisons also exist (Meek et al 2002;Roth et al 2008;Sjodin et al 2008;Čížek et al 2012).…”

Relationships between landscape and moth diversity in Mediterranean mountain forest ecosystems at multiple spatial scales

“…In alcuni lavori è emerso che specie stenoecie e con scarsa capacità di dispersione sono correlate alla diversità del paesaggio solo considerando piccole scale spaziali, ossia buffer inferiori ai 500 m e che, al contrario, per le specie generaliste si apprezzano gli effetti della diversità di paesaggio a scale spaziali più ampie (Bergman et al 2004, Krauss et al 2003, Dover & Settele 2009, Scalercio et al 2012. La scelta del buffer ottimale per la correlazione tra diversità del paesaggio e comunità di Lepidotteri resta comunque un parametro di fondamentale importanza negli studi ecologici.…”

Movement, demography and behaviour of a highly mobile species: A case study of the black-veined white, Aporia crataegi (Lepidoptera: Pieridae)

“…This kind of traditional management should not include the use of fertilizers and pesticides, and other disturbing factors such as urbanisation and colonization by non native species. This study clearly emphasises that only the preservation of areas that are large enough to include not only all the appropriate habitats, but also a suitable matrix of them (Bergman et al, 2004(Bergman et al, , 2007Liivamägi et al, 2014) may be crucial for the persistence and dynamics of a metapopulation and the long term existence (Thomas & Jones, 1993) of this highly mobile species. This, however, can be achieved within large areas where nature conservation is high on the priority list, and Natura 2000 areas could well serve this purpose.…”