Wetland butterfly thriving in abandoned jungle: Neptis rivularis in the Czech Republic.

With ongoing insect declines, species expanding in distribution and abundance deserve attention, as understanding their success may help design conservation strategies for less successful species. Common causes of these successes include warmer climates, novel resources, and exploiting land use change, including land abandonment. These factors affect the nymphalid butterfly Neptis rivularis, developing on Spiraea spp. shrubs and reaching the north-western limits of its trans-Palearctic distribution in Central Europe. We combined mark-recapture, behaviour analysis, and distribution modelling to study N. rivularis in wetlands of the Trebonsko Protected Landscape (IUCN category V). The long-living adults (up to 4 weeks) spent a considerable amount of time searching for partners, ovipositing and nectaring at Spiraea shrubs, alternating this with stays in tree crowns, where they located cool shelters, spent nights, and presumably fed on honeydew. They formed high-density populations (310 adults/ha), exploiting high host plant abundance. They adhered to floodplains and to conditions of relatively mild winters. The ongoing Spiraea encroachment of abandoned alluvial grasslands is, thus, a transient situation, ultimately followed by forest encroachment. Rewilding the habitats by introducing native ungulates presents an opportunity to restore the disturbance regime of the sites. The increased resource supply combined with a warming climate has opened up temperate Europe to colonization by N. rivularis.

Perishing rich, expanding poor: Demography and population genetic patterns in two congeneric butterflies.

In human-altered landscapes, specialist butterflies typically form spatially restricted populations, genetically differentiated due to dispersal restrictions. Generalists, in contrast, display minimum differentiation but high genetic diversity. While local-level actions suffice to conserve specialists and landscape-level actions are necessary for generalists, minimum information exists regarding conservation of species with intermediate features. We targeted two congeneric butterflies, the recently re-expanding Argynnis adippe and the strongly declining A. niobe, co-occurring in the pastoral landscape of the Carpathian Mountains, Czech Republic. We integrated species distribution models, mark-recapture and microsatellite analysis to compare their habitat requirements, adult demography, dispersal and genetic patterns, and expanded the genetic analysis across the Carpathian Arc and beyond to delimit spatial conservation units. In two mountain valleys, both species formed interconnected populations numbering thousands of individuals. Mobility patterns suggested the populations' interconnection across the Czech Carpathians. Genetic diversity was extremely poor in the nonthreatened A. adippe and moderate in the declining A. niobe. No population differentiation was detected within the Czech Carpathians (~1500 km2 ). Low genetic diversity and no differentiation was preserved in A. adippe across East Central Europe, whereas in A. niobe, populations from Serbia were differentiated from the Carpathian Arc + Alps. The high adult mobility linked to low differentiation probably reflects the distribution of larval resources, historically widespread but sparse and currently declining for A. niobe (grazing-disturbed grounds), while currently increasing for A. adippe (abandonment scrub, disturbed woodlands). Units as large as entire mountain systems define population boundaries, and hence conservation management units, for both species.

Importance of functional classification in the use of carabids for the environmental risk assessment of the GE crops and other agricultural practices.

Carabids (Coleoptera: Carabidae) seem to be suitable bioindicators of the environmental impacts of novel agrotechnologies, including deployment of the genetically engineered (GE) crops. In this article, we describe our effort to employ carabids in the environmental risk assessment (ERA). GE maize MON88017, its near-isogenic hybrid nontreated or treated with the soil insecticide chlorpyrifos, and two reference hybrids were used to compare three different ways how to utilize carabids in ERA. The analysis of abundance of all captured carabids or of the most abundant carabid species did not disclose any differences between the treatments. The analysis based on the categories of functional traits revealed distinct features of some treatments and proved suitable for ERA because it permitted field data transportability in spite of different species compositions. Our results indicate that GE maize has no detrimental environmental effect. On the other hand, we found significant trends toward lower abundance and lower species number (including analysis of all carabid species together) in plots treated with the insecticide, and some tendencies to higher abundance and higher species number in plots sown with the reference hybrid PR38N86. Using functional group indicators allows identification of unintended changes in ecological functions of agroecosystem and comparability across geographies. We recommend data evaluation at the level of the categories of functional traits in ERA of GE crops and other agricultural practices.