PMMB Cable Pearls: A Dual‑Cable, Bird‑Safe Ecological Corridor Using Sporopollenin Skins for Micro‑Water Harvesting and Aero‑Biosurveillance

Objective: To define a practical, bird‑safe overhead corridor that couples line‑marking (flight diverters) with standardized aero‑biological sampling (PMMB‑Pad) for urban ecology and public health use. Approach: We propose a dual‑cable layout where a Primary Ecological Cable (PEC) carries modular Cable Pearls (≤150 g each) functioning as both bird‑visibility markers and aero‑bio samplers. The MVP targets a 200 m span with 10 Pearls. Weekly Hirst‑style cassettes generate pollen/bioaerosol fingerprints; before‑after‑control‑impact (BACI) observations quantify avian risk reduction. Optional co‑benefits include micro fog/dew harvesting (mL‑day⁻¹) via passive micro‑filaments and a biomimetic PMMB‑Skin (sporopollenin) to enhance droplet/pollen pinning. Safety is enforced via low‑Cd geometry, bottom drains, and 50–120 N breakaway links. Expected Outcomes: (i) −70–90% reduction in risky avian flight proxies vs. unsignaled spans; (ii) reproducible weekly aero‑bio signatures with ≥15% richness gain over controls; (iii) clean operations SOP (≤5 min swap) and ready‑to‑fund engineering numbers (load budgeting, spacing). Significance: Positions overhead corridors as measurable ecological infrastructure, with modular extensions (e.g., off‑span biochar cartridges at hydrologic hotspots) while maintaining strict no live‑microbe release and city‑friendly maintenance.