Eavesdropping on dolphins: Investigating the habits of bottlenose dolphins (Tursiops truncatus) through fixed acoustic stations

PLoS One. 2019 Dec 5;14(12):e0226023. doi: 10.1371/journal.pone.0226023. eCollection 2019.

Abstract

This study investigates the bottlenose dolphin (Tursiops truncatus, Montagu 1821) habitat use in the Portofino marine protected area (NW Italy) and adjacent waters, a core area for the dolphins and a highly touristic area in the Mediterranean Sea. A permanent automated real-time passive acoustic monitoring system, able to detect and track dolphins continuously, was tested in the area within the activities of the Life+ Nature project ARION. The habits of bottlenose dolphins was investigated considering the resident rate inside the area, which quantifies the amount of time dolphins spent in these waters, by means of random forest regression. The dependency of dolphin resident rate was analyzed in relation to four explanatory variables: sea surface temperature, season, time of day, and proximity to the coast. Dolphins spent more time in the area during spring and when sea surface temperature ranged between 15-16°C. Summer resulted the season with lower dolphin residency with significant difference between working day and weekend, in the last the lowest residency was recorded. Main findings provide important information to properly manage the area in order to protect bottlenose dolphins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acoustics*
  • Animals
  • Bottle-Nosed Dolphin*
  • Ecosystem*
  • Environmental Monitoring / instrumentation
  • Environmental Monitoring / methods*
  • Regression Analysis
  • Seasons

Grants and funding

This work has been funded by the European Commission within the framework of the LIFE+ program (grant number: LIFE09 NAT/IT/000190 ARION). The funding organization did not play any role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript and only provided financial support in the form of authors' salaries and research materials. The beneficiaries of the project are: 1. University of Genova (coordinating beneficiary); 2. Direzione Marittima di Genova (associated beneficiary); 3. Portofino Marine Protected Area (associated beneficiary); 4. Softeco Sismat S.r.l. (associated beneficiary). The authors Christian Melchiorre (ChM) and Gianni Viano (GV) are employed by the commercial IT company named Softeco Sismat S.r.l. that provided support in the form of salaries for these authors [ChM, GV], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.