Mapping butterfly distribution in habitat hotspots on the Island of Gozo (Rhopalocera – Lepidoptera)

Abstract

Butterflies are widely recognised for their significance as bioindicators. However, their spatial distribution remains poorly documented across small Mediterranean islands. This study maps butterfly distribution across the island of Gozo, assesses habitat and biotope characteristics in terms of species occurrence, and explores the existence of connectivity between habitat patches. Walkover field surveys are conducted across 44 days of fieldwork, between July 2025 and April 2026, focusing on 11 pre-selected sites of ecological significance. A total of 399 individuals across 13 species are recorded and their spatial distribution is analysed through GIS. Species richness is highest in mosaics of garrigue, steppe and agricultural land, particularly at Dwejra, Ramla Bay, and the Qala sites (Taċ-Ċawl and Wileġ). Grassland specialist species including Coenonympha pamphilus and Maniola jurtina hyperhispulla, both of which face significant declines, are recorded exclusively from the Qala sites. Seasonal distribution analysis reveals peak activity in autumn and spring, demonstrating seasonal patterns with influxes of migratory species including Vanessa cardui and Colias croceus during biannual passage between North Africa and Europe, with the Maltese islands acting as a crucial mid-sea migratory corridor stepping stone. While some sampling limitations are noted, the study provides an important baseline for spatial information on butterfly distribution on Gozo. Increasing pressure from land-use change and overdevelopment risk fragmenting vital habitat refugia, especially for specialist and migratory species (latter group is crucial in augmenting resident populations), highlighting the urgent need for long-term butterfly monitoring to inform conservation planning.