Acoustic Highway System (AHS-ANC): Mitigating Anthropogenic Underwater Noise and Restoring Pelagic Fish Migration via Directional Active Noise Cancellation Smart Buoys

Over the past five decades, ambient low-frequency underwater noise (30–100 Hz) in the North Pacific Ocean has escalated by approximately 12 dB—an energy increase exceeding 15-fold—driven by commercial shipping corridors and heavy distant-water fishing fleets. This frequency band overlaps directly with the acoustic sensitivity of pelagic teleosts (e.g., Pacific saury Cololabis saira, sardines, and mackerel) and perceived predation calls from cetaceans. While conventional hypotheses attribute the catastrophic collapse of coastal Japanese saury fisheries (a 94% decline from >350,000 metric tons in the 1980s to ~20,000 tons in the 2020s) solely to marine heatwaves and current shifts, we demonstrate an unprecedented statistical correlation (r = 0.947) between ocean ambient noise rise and the eastward displacement of saury fishing grounds by ~2,000 km into high-seas international waters. To address this, we propose the Acoustic Highway System with Active Noise Cancellation (AHS-ANC): an array of autonomous, solar-and-wave-powered smart buoys deployed along the 152°E–154°E meridian. Each buoy incorporates bi-directional acoustic emission:1. Eastward (Offshore): Emits directional low-frequency vessel/predator deterrent signals to push pelagic schools westward;2. Westward (Inshore): Emits anti-phase acoustic waves via Least Mean Squares (LMS) adaptive filters to cancel coastal shipping noise leakage by 15–20 dB. Two-dimensional hydroacoustic wavefield and agent-based fish trajectory simulations confirm that AHS-ANC creates an acoustic corridor ("silent sanctuary") that restores innate, genetically hardwired migratory pathways ("oceanic butterfly paths"), guiding fish stocks back to coastal EEZ waters. With an estimated Phase 1–3 deployment cost of ~$3.7M USD compared to annual fishery losses exceeding $200M USD, AHS-ANC represents a highly feasible, non-invasive geo-ecological restoration technology. This research package includes full engineering specifications, 50-year historical noise correlation datasets, 2D wavefield simulation source code, and cryptographic timestamp verification (SHA-256: 9515c27bd070b1d4ad5e00113ce5b5a5880eb2ec5c028610ed8f0233f63f4d6f).