Silvia Colla

The soundscape of a mussel farm: Biophony and man-made noise levels

During the summer of 2015, four Passive Acoustic Monitoring (PAM) surveys were carried out over a mussel farm in the Venetian (Italy) littoral zone at night-time hours. A qualitative and quantitative analysis of the soundscape was carried out. The high frequencies component of the soundscape (i.e above 2 kHz) was dominated by snapping shrimps sounds, while the low frequency component (i.e. below 2 kHz) was characterized by fish vocalization, mainly emitted by Sciaena umbra (Sciaenidae), with less frequent occurrences emitted by Gobidae spp. S. umbra highest vocal activity was recorded from June to August inside the mussel farm. The low frequency component of the soundscape was dominated by boat noise; in particular, low frequency noise (i.e. below 4 kHz) emitted by commercial ships and passenger cruises. The Acoustic Complexity Index (ACI) was found to increase concurrently with the number of S. umbra vocalizations: ACI highest values corresponded with S. umbra chorus recorded during July. The results of ...

Using passive acoustics to assess habitat selection by the brown meagre Sciaena umbra in a northern Adriatic Sea mussel farm: HABITAT SELECTION BY SCIAENA UMBRA

Passive acoustic monitoring (PAM) of the brown meagre Sciaena umbra was conducted in a northern Adriatic Sea mussel farm. The level of acoustic activity was found to be constantly high from June to August before declining sharply in September and there was significantly higher acoustic activity in the structured habitats within the mussel farm than in the bare sandy bottom outside the farm. Results are discussed in the context of the use of this species as an indicator species of artificial rocky habitats along the Mediterranean coastal environments.