Using occurrence data to evaluate extinction reveals a strong resilience of butterflies in a National Park of Southern Europe (Alta Murgia National Park)

Abstract

Butterflies from southernmost European regions encompass a large fraction of faunistic and genetic diversity but are also at the forefront of extinction risk for climate change. Nevertheless, monitoring schemes aimed at detecting their population trends were only recently established. In this study, we gathered all occurrence records of the 81 species of butterflies recorded for the Alta Murgia National Park (Italy, Apulia), a prime conservation area for butterflies. By using literature, citizen science, and unpublished sample data, we traced potential extinctions since 1966. We also provided a dedicated index to evaluate the potential extinction at the whole community level. We found that among the 29 species recorded before 2009, three were not recovered from 2009 to 2021. Another group of nine species was not recorded in the last five years. However, given the not standardized sampling methodology and the possibility that apparently disappeared species were due to inaccurate identification, we conclude that the butterfly community of the Park is showing a strong resilience. We hypothesize that such resilience may be attributed to the existence of the protected area and the presence of heterogeneous environments, which allow to buffer climatic changes and any other negative anthropic effects. The objective recognition of rare species in the surrounding region of 200 km ray also allowed identifying which species should be considered as prime targets for the conservation of local and regional diversity.