Published July 26, 2017 | Version v1
Journal article Open

Marine soundscape as an additional biodiversity monitoring tool: A case study from the Adriatic Sea (Mediterranean Sea)

  • 1. Dipartimento di Scienze Pure ed Applicate, Università degli Studi di Urbino Carlo Bo, Urbino, Italy
  • 2. Dipartimento di Scienze della Vita e dell'Ambiente (DISVA), Università Politecnica delle Marche, Ancona, Italy
  • 3. Dipartimento di Scienze della Vita e dell'Ambiente (DISVA), Università Politecnica delle Marche, Ancona, Italy; Stazione Zoologica Anton Dohrn, Napoli, Italy

Description

Acoustic monitoring can provide essential information on marine environments, including insights into ecosystem functioning and marine biodiversity monitoring. However, data on species acoustic behavior and
ecoacoustics studies in the Mediterranean Sea are still extremely scarce and this limits our ability to use soundscape features in monitoring studies. Here we present the results of a soundscape investigation conducted on shallow hard bottoms of the Adriatic Sea (Central Mediterranean basin). We report the presence of diverse circadian rhythms recorded in two different months, July and September. A power spectral density (PSD) was used to assess the overall spectral composition over time, and the Acoustic Complexity Index (ACI), was identified as a proxy for marine sounds of biological origin. The dominant component of the biological soundscape was composed of snapping shrimps and fishes. Spectral characteristics varied significantly both daily and between the two months. For frequencies>620 Hz (i.e., associated to snapping shrimp activity), both PSD and ACI were higher in July than in September. The same circadian rhythm was reported in both sampling periods, with the presence of snaps for 24 h a day, but with significantly lower intensity during daylight hours and pitches at the beginning and ending of the night. At lower frequencies (i.e.,<620 Hz), fish vocalizations mostly occurred during the night. Higher values of ACI were recorded during the night in both months, whereas the presence of anthropogenic noise caused opposite results in PSD levels. Noise was associated with higher PSD and ACI at the peak frequency of the snaps, suggesting a stimulation in snapping activity. Our findings provide new insights on the marine biological soundscape and on the potential use of ecoacoustics in future monitoring programs.Acoustic monitoring can provide essential information on marine environments, including insights into ecosystem functioning and marine biodiversity monitoring. However, data on species acoustic behavior and ecoacoustics studies in the Mediterranean Sea are still extremely scarce and this limits our ability to use soundscape features in monitoring studies. Here we present the results of a soundscape investigation conducted on shallow hard bottoms of the Adriatic Sea (Central Mediterranean basin). We report the presence of diverse circadian rhythms recorded in two different months, July and September. A power spectral density (PSD) was used to assess the overall spectral composition over time, and the Acoustic Complexity Index (ACI), was identified as a proxy for marine sounds of biological origin. The dominant component of the biological soundscape was composed of snapping shrimps and fishes. Spectral characteristics varied significantly both daily and between the two months. For frequencies>620 Hz (i.e., associated to snapping shrimp activity), both PSD and ACI were higher in July than in September. The same circadian rhythm was reported in both sampling periods, with the presence of snaps for 24 h a day, but with significantly lower intensity during daylight hours and pitches at
the beginning and ending of the night. At lower frequencies (i.e.,<620 Hz), fish vocalizations mostly occurred during the night. Higher values of ACI were recorded during the night in both months, whereas the presence of anthropogenic noise caused opposite results in PSD levels. Noise was associated with higher PSD and ACI at the peak frequency of the snaps, suggesting a stimulation in snapping activity. Our findings provide new insights on the marine biological soundscape and on the potential use of ecoacoustics in future monitoring programs.

Notes

This manuscript has been financially supported by the Project DEVOTES funded by the European Union under the 7th Framework Programme (Grant Agreement No. 308392), and by EU Horizon2020 project MERCES (Grant agreement n. 689518). We thank the KOMAROS scuba-diver association for providing support in completing the checklist of fish species of the study area. This paper reflects only the authors' views and the funders cannot be held responsible for any use that may be made of the information contained there in. Copyright © 2016. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC-BY) license (http:// creativecommons.org /licenses/by/4.0/).

Files

Pieretti et al 2017 - post-print - Marine soundscape as an additional biodiversity monitoring tool.pdf

Additional details

Funding

MERCES – Marine Ecosystem Restoration in Changing European Seas 689518
European Commission