Sound Highways of the Sea: Mapping Acoustic Corridors for Whales and Fish in Colombia’s Pacific

Maria Paula Rey Baquero – rey_m@javeriana.edu.co
Instagram: @mariapaulareyb
Pontificia Universidad Javeriana
Fundación Macuáticos Colombia
Bogotá
Colombia

Additional Authors:
Kerri D. Seger
Camilo Andrés Correa Ayram
Natalia Botero Acosta
Maria Angela Echeverry-Galvis

Project Ports, Humpbacks y Sound In Colombia – @physicolombia
Fundación Macuaticos Colombia – @macuaticos
Semillero Aquasistemas – @aquasistemaspuj

Popular version of 4aAB5 – Modeling for acoustical corridors in patchy reef habitats of the Gulf of Tribugá, Colombia
Presented at the 188th ASA Meeting
Read the abstract at https://eppro01.ativ.me//web/index.php?page=Session&project=ASAICA25&id=3864155

–The research described in this Acoustics Lay Language Paper may not have yet been peer reviewed–

Sound plays a fundamental role in marine ecosystems, functioning as an invisible network of “pathways” or corridors that connect habitat patches and enable critical behaviors like migration, communication, and reproduction. In Colombia’s northern Pacific, one of the most biodiverse regions, the Gulf of Tribugá stands out for its pristine soundscape, dominated by the sounds of marine life. Designated a UNESCO Biosphere Reserve and a “Hope Spot” for conservation, this area serves as a vital nursery for humpback whales and supports local livelihoods through ecotourism and artisanal fishing. However, increasing human activities, including boat traffic and climate change, threaten these acoustic habitats, prompting researcher on how sound influences ecological connectivity—the lifeline for marine species’ movement and survival.

This study in Colombia’s Gulf of Tribugá mapped how ocean sounds connect marine life by integrating acoustic data with ecological modeling. Researchers analyzed how sound travels through the marine environment, finding that humpback whale songs (300 Hz) create natural acoustical corridors along coastal areas and rocky islands (‘riscales’). These pathways, though occasionally interrupted by depth variations, appear crucial for whale communication, navigation, and maintaining social connections during migration. In contrast, fish calls (100 Hz) showed no detectable sound corridors, suggesting fish may depend less on acoustic signals or use alternative navigation cues like wave noise when moving between habitats.

Photographs of some of the recorded fish species. Source: Author

The research underscores that acoustical connectivity is species-specific. While humpback whales may depend on sound corridors and prioritize long-distance communication, fish may prioritize short-range communication or other environmental signals. At any distance, noise pollution disrupts these systems universally: The bubbling/popping sounds created by spinning boat propellers, for instance, generate frequencies that can covers up the whale songs and fish calls and degrade habitat quality, even if fish are less affected over the same distances that whales are. Background noise shrinks and breaks up the underwater corridors that marine animals use to communicate and navigate, harming their underwater sound habitat.

Figure 1. Received sound levels when emitted by singers (a) without noise and (b) with background noise, at a grain size of 2 Φ. The left column shows conditions without background noise, and the right column shows conditions with noise. Sound intensities most likely to be heard by a humpback whale at 200 Hz are shown in green, less likely sounds in orange, and inaudible sounds in black. Source: Author

Noise pollution alters behaviors and acoustic corridors humpback whales rely on for communication and navigation in Colombia’s Pacific waters. Notably, the fish species studied showed no sound-dependent movement, suggesting their reliance on other cues. The study advocates for sound-inclusive conservation, proposing that acoustic data (more easily gathered today via satellites, field recordings, and public databases) should join traditional metrics like currents or temperature in marine management. Protecting acoustic corridors could become as vital as safeguarding breeding grounds, especially in biodiverse hubs like Tribugá.

This work marks a first step towards integrated acoustical-ecological models, offering tools to quantify noise impacts and design smarter protections. Future research could refine species-specific sound thresholds or expand to deeper oceanic areas. For now, the message is preserving marine ecosystems requires listening, not just looking. Combining efforts to lessen human noise by using mapped soundscapes to target critical corridors could help in the conservation of marine species.