Pheromone Trap (BCWT) for collection of O. eremita. A. Trap equipped with a tube containing pheromone, B. Positioning on a branch of a tree, C. Inserting the funnel into the collector, D. a hermit beetle caught at the bottom of the collector (Photo by E. Capogna A-B, F. Bernardini C-D). Material for building one BCWT: 2 black panels (25 x 350 cm), 1 plastic funnel (Ø 30 cm), 1 collector made of a plastic container with a screw cap (vol. 500 ml), 1 hook made from iron wire, 1 small iron wire hook to secure the tube on a panel; Commitment: 2 days, 2 operators, 24 hours per person; Construction period: winter and / or spring months before monitoring.