Predicting the habitat suitability and hotspot regions of the near threatened Socotra bluet on the Socotra Archipelago using an integrated modelling approach.

Abstract

The Socotra bluet (Azuragrion granti) is an endemic, Near Threatened damselfly restricted to the Socotra Archipelago whose persistence depends on scarce freshwater refugia under a changing climate. We used an integrated modelling framework, MaxEnt species distribution models coupled with spatial hotspot statistics (Getis-Ord Gi* and Local Moran's I) and landscape metrics, to map current and future habitat suitability (SSP126, SSP245, SSP370 for 2021-2040 and 2041-2060) and to identify priority conservation zones. Model performance was robust (AUCs 0.752-0.763; TSS 0.601-0.696). Contrary to expectations of wholesale range contraction, projections indicate a marked redistribution with net increases in Moderate to Very High suitability classes (Very High suitability expanding from 2.3% presently to as much as 16-19% of the island under several future scenarios) alongside spatially clustered increases in unsuitable habitat. Decadal hotspot analysis and cluster detection revealed persistent and intensifying suitability hotspots concentrated in eastern Socotra, notably the Hagher/Hajhir highlands, while persistent coldspots and widespread clustering of unsuitable areas flagged emerging threat zones. Spatially explicit results (persistent coldspots = 2,247.75 km²; intensifying hotspots = 1,296 km²; consecutive hotspots = 850.5 km²) highlight both refugia and areas of rapid degradation. We identify a contiguous corridor of priority sites in the eastern highlands and recommend community-co-managed protection of their hydrological features as the primary conservation action, alongside field verification of a single isolated priority site detected in western Socotra. These results provide a spatially explicit blueprint for safeguarding A. granti and associated freshwater biodiversity on Socotra under multiple climate futures.