EUROPEAN JOURNAL OF ENTOMOLOGY

Eur. J. Entomol. 122: 308-322, 2025 | DOI: 10.14411/eje.2025.035

Nature conservation and insect decline in Central Europe: Loss of Lepidoptera in key protected sites is accompanied by substantial land cover changesOriginal article

Gwendoline PERCEL ORCID...¹, Lukas CIZEK ORCID...^{1, 2}, Jiri BENES ORCID...¹, Jan MIKLIN ORCID...^{1, 3}, Pavel VRBA ORCID...¹, Pavel SEBEK ORCID...^{1, *}

¹ Biology Centre of the Czech Academy of Sciences, Institute of Entomology, Branišovská 31, 37005 České Budějovice, Czech Republic; e-mails: g.percel@hotmail.fr, lukascizek@gmail.com, benesjir@seznam.cz, miklin@email.cz, vrba_pavel@centrum.cz, pav.sebek@gmail.com

² Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic

³ Regional Museum in Mikulov, Mikulov, Czech Republic

The insect biodiversity crisis affects diverse cultural landscapes as well as natural and semi-natural habitats. Accordingly, the effectiveness of protected areas in conserving insect communities needs to be evaluated. We employed photo-interpretation of aerial photographs from the past (1938-1947) and present (2014-2019) to analyse changes in natural habitats with diverse canopy cover in seven long-term protected areas (jointly called 'reserves') in the Czech Republic, Central Europe, and evaluated potential links between these changes and butterfly and moth (Lepidoptera) declines. We observed a marked decrease in habitat heterogeneity, largely due to the expansion of closed-canopy forests at the expense of semi-open habitats (e.g. forest steppes, open woodlands) and open grasslands. An analysis of faunistic records of 162 species of butterflies and 160 species of macro-moths before and after 2000 showed that, on average, the reserves have experienced losses of 26% of butterfly species and 19% of moth species. Trait-based analyses suggested that the losses were associated with particular life-history traits. Non-generalist butterflies with a short period of seasonal flight activity, and moths associated with grasslands and with non-feeding adults, had a greater probability of going missing (meaning potentially locally extinct) in the reserves. These findings suggest that conservation efforts should prioritise active management that aims to restore habitat heterogeneity in order to mitigate the ongoing trend of insect decline.

Keywords: Biodiversity conservation, land use, land cover, canopy openness, butterflies and moths, land abandonment, succession, homogenization

Received: February 25, 2025; Revised: October 4, 2025; Accepted: October 4, 2025; Published online: November 12, 2025  Show citation