Assessing habitat connectivity and conservation strategies for Brachytrupes megacephalus in Malta

Abstract

The Giant Sand Cricket, Brachytrupes megacephalus, is indigenous to the Mediterranean and the Maghrebian Sahara, of conservation concern whose Maltese populations are increasingly threatened by habitat fragmentation. This study assesses the conservation status, habitat connectivity, and spatial distribution of the species across the Għadira population and the fragmented Aħrax metapopulation in northern Malta. Bioacoustic surveys, habitat mapping, direct field observations, and GIS-based spatial analyses are conducted to evaluate population density, dispersal potential, and barriers to movement between habitat patches. Seasonal observations were additionally used to assess temporal shifts in habitat use, while a pilot translocation exercise explores the feasibility of ex-situ population expansion as part of a conservation strategy. Results indicate substantial habitat fragmentation and a reduction in occupied habitat areas, particularly within the Aħrax metapopulation, where several previously recorded sites no longer show evidence of occupation. Habitat suitability is strongly influenced by substrate properties, vegetation density, and exposure to climatic conditions. Physical barriers, including roads, rubble walls, and drainage infrastructure, are seen to restrict connectivity between habitat patches and potentially limit dispersal. In contrast, the Għadira population displays comparatively high local densities, with one specific occupied field containing approximately one burrow per 1.89 m². Seasonal observations suggest redistribution between reserve habitats and adjacent agricultural land, while behavioural observations reveal increased intraspecific competition associated with spatial restriction and habitat degradation. The pilot translocation ex-situ exercise highlights challenges associated with receptor-site suitability and habitat exposure, emphasising the importance of careful site selection in future conservation interventions. Predation pressures, particularly from stray cats, is also identified as an important conservation concern within cricket-occupied habitats. The findings of this study demonstrate the importance of maintaining habitat connectivity, protecting and restoring dune systems, and integrating long-term monitoring with adaptive management strategies. These results provide updated ecological data and evidence-based recommendations to support future conservation planning and long-term persistence of B. megacephalus in Malta.