Overview
- Researchers recorded 24 continuous hours of audio from seven bottlenose dolphins at Oltremare Marine Park in 2021, spanning feeding, trainer-led exercises, play, and unstructured periods.
- Analysis showed significantly higher vocalization rates during structured sessions than during unstructured time (p < 0.001) across all vocalization types.
- Play elicited the highest rates of pulsed sounds (p < 0.01), indicating especially intense social and exploratory engagement during these sessions.
- The team manually extracted 3,111 whistles and used an automated method to identify 1,277 pulsed vocalizations, classifying click trains, burst-pulse sounds, and feeding buzzes using SNR and inter-click interval criteria.
- The full, annotated dataset is open access through PLOS ONE, and the authors note limits from the small sample and single-day scope while urging broader, longer-term studies to refine welfare and enrichment practices.