Assessing habitat vulnerability for the conservation of Brachytrupes Megacephalus (Orthoptera: Gryllidae)

Abstract

The stenoecious gryllid Brachytrupes megacephalus (Lefebvre, 1827), has an “unfavourable-bad” status within its European territories. It is included within Annexes II and IV of the Habitats Directive (92/43/EEC) and the revised Annex VI of the Bern Convention. The species occurs within fragmented patches of malleable substrate, predominantly on the north eastern extremity of the island of Malta, where its subpopulations face numerous threats. Through groundthruting, drone photography and statistical analysis, the present research assesses the species’ distribution, demographic fluctuations and threats in order to characterise pressures leading to its foremost vulnerabilities. Data demonstrates a general positive trend, however, this increase is not mutual among all sites in which the cricket is found, as evidence points towards a decline where most minor populations are concerned. In most sites, habitat fragmentation, anthropogenic disturbance and invasive pest species threaten the stenoecious cricket and degrade its viable habitat. These, coupled with sea level rise and storm surge for low lying sites, encompass the predominant threats facing Maltese Brachytrupes megacephalus populations. Results suggest that cohesive legislative action is required in order to rehabilitate and maintain current populations, which can only be achieved by limiting these threats, securing the remaining habitat areas and ensuring that connectivity between them persists.