Acoustic Situational Awareness in the Strait of Gibraltar: Field Notes from the XV SEC Málaga Congress 2026 and Recent Literature

Conversations at the XV Congress of the Spanish Cetacean Society (SEC 2026, Málaga) made one thing very clear: managing vessel-orca interactions through delayed sighting reports and sporadic aerial passes simply cannot keep up with real-world conditions at sea. This on-the-ground reality strongly supports the core premise of my working paper, Passive Acoustic Monitoring for Iberian Orca Conservation and Maritime Safety: Managed Coexistence in the Strait of Gibraltar (Scholl, 2026). If we want to safeguard both cruising vessels and these endangered whales, our maritime safety architecture has to move to automated, real-time underwater acoustic detection.

The field data presented in Málaga underline these blind spots. While Alfredo López showed that overall interactions dropped 27.9% from their 2023 peak across 2,529 deduplicated records, encounters throughout the second half of the year in the Strait have remained stubbornly flat. At the same time, Ruth Esteban’s dedicated vessel transects found deep-diving odontocete rates up to thirty times higher than official aerial surveys had recorded, proving how easily overhead flights miss animals traveling at depth.

Recent studies also challenge our reliance on physical tagging. Francesco Ciotoli and Txema Brotons documented immediate distress squeals and fractured social codas when a sperm whale was struck with an intradermal tag. For a critically endangered group of roughly 30 to 40 animals, taking those physical risks makes little sense. Moreover, work by Rudd et al. (2024) detailed how orcas cooperatively hunt and handle large bluefin tuna, pinpointing the trophic incentive behind longline depredation. Given that Rojano-Doñate showed close-range vessel traffic cuts whale feeding bouts, preventing close encounters serves animal welfare just as much as rudder protection.

The engineering tools to run non-invasive listening grids are already here. Lüke, Almunia, and their team (2026) verified an edge-AI pipeline running on a modest Raspberry Pi 3B+, executing real-time call discrimination (99%) and classification (81%) in just 50 milliseconds. Santiago Campo Jurado showed how commercial subsea telecom cables can turn into dense acoustic arrays via Distributed Acoustic Sensing (DAS) and YOLO11n-OBB classifiers. Most importantly, bridge simulator trials by Juan Ignacio Alcaide proved that giving watchstanders early behavioral warnings cuts vessel reaction times at speeds of 30+ knots from 42 down to 21 seconds and widens passing clearances to 410 meters. Linking autonomous acoustic nodes directly to bridge navigational feeds gives us not only a practical but rather also a humane way forward.

Real-time alerts based on reliable data enable a shared common operating picture, which has the capacity to effectively protect both Iberian orcas and human vessel operators in the busy Strait of Gibraltar.