Full-duplex acoustic interaction system for cognitive experiments with cetaceans

Abstract

Cetaceans show high cognitive abilities and strong social bonds. Acoustics is their primary modality to communicate and sense the environment. Research on their echolocation and vocalizations with conspecifics and with humans typically uses visual and tactile systems adapted from research on primates or birds. Such research would benefit from a purely acoustic communication system in which signals flow in both directions simultaneously. We designed and implemented a full duplex system to acoustically interact with cetaceans in the wild, featuring digital echo-suppression. We pilot tested the system in Arctic Norway and achieved an echo suppression of 18 dB leaving room for technical improvements addressed in the discussion. Nevertheless, the system enabled vocal interaction with the underwater acoustic scene by allowing experimenters to listen while producing sounds. We describe our motivations, then present our pilot deployment and give examples of initial explorative attempts to vocally interact with wild orcas and humpback whales.

Sonic enrichment at the zoo

“…Various species of primates and birds have been shown to be seemingly aware of the impact of their actions on others' behavior (Byrne & Bates, 2010) and are able to grasp a human's intention (Suddendorf & Whiten, 2001) or, at least, to engage socially as well as gaze directly into someone's face (Nielsen, 2009;Carpenter & Call, 2009). Previous work on using underwater technologies for marine mammals including keyboards for human-dolphin communication (Reiss & McCowan, 1993;Herzing, 2016) and language understanding systems (Pack, 2018), as well as full-duplex systems for orca vocal communication (Rychen et al, 2022) also illustrate the potential of providing animal agency in the context of Human-Animal Relationship (HAR) and communication for enrichment. Far from serving only as entertainment for the animals, such HAR interactions appear to be related to general social and communicative needs and could possibly be enhanced with auditory enrichment.…”