Will refaunation by feral horse affect five checkerspot butterfly species (Melitaea Fabricius, 1807) coexisting at xeric grasslands of Podyji National Park, Czech Republic?

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.

Abundant Citizen Science Data Reveal That the Peacock Butterfly Aglais io Recently Became Bivoltine in Belgium

Simple Summary

The peacock butterfly is abundant and widespread in Europe. It used to have a single generation per year: adults born in summer overwintered and reappeared in spring to reproduce. However, recent flight patterns in western Europe show three peaks during the year: a first one in spring (overwintering butterflies), a second one in early summer (offspring of the spring generation), and a third one in autumn. Hitherto, it was unclear whether this third autumn flight peak was a second new generation or consisted of butterflies flying again in autumn after a summer rest. Based on hundreds of thousands of observations and thousands of pictures submitted by naturalists from the public to the online portal ‘observation’ in Belgium, we demonstrate that Peacocks shifted towards two new generations per year in recent decades. Mass citizen science data has become increasingly important in tracking the response of biodiversity to rapid environmental changes (e.g., climate change).

Abstract

The peacock butterfly is abundant and widespread in Europe. It is generally believed to be univoltine (one generation per year): adults born in summer overwinter and reappear again in spring to reproduce. However, recent flight patterns in western Europe mostly show three peaks during the year: a first one in spring (overwintering butterflies), a second one in early summer (offspring of the spring generation), and a third one in autumn. It was thus far unclear whether this autumn flight peak was a second new generation or consisted of butterflies flying again in autumn after a summer rest (aestivation). The life cycle of one of Europe’s most common butterflies is therefore still surprisingly inadequately understood. We used hundreds of thousands of observations and thousands of pictures submitted by naturalists from the public to the online portal observation.orgin Belgium and analyzed relations between flight patterns, condition (wear), reproductive cycles, peak abundances, and phenology to clarify the current life history. We demonstrate that peacocks have shifted towards two new generations per year in recent decades. Mass citizen science data in online portals has become increasingly important in tracking the response of biodiversity to rapid environmental changes such as climate change.