Exploratory Study On The Acoustic Characterization Of Transit And Trawling Noise From Fishing Vessels In The Strait Of Sicily

Anthropogenic noise is a serious concern for marine ecosystems, as described in Descriptor 11 of the EU Marine Strategy Framework Directive (MSFD). Among human-made sounds, bottom trawling is a fishing activity that has the potential to impact the underwater environment. The main aim of this study was to analyze the acoustic emission of bottom trawling using a single recorder deployed in offshore waters of western Sicilian coast (Strait of Sicily). Acoustic data were collected from 18 February to 27 April 2022 at 192 kHz sample rate, with 50% duty cycle (5 min every 10 min), for a total of 9,473 5-min recordings (about 1 TB). Additionally, Automatic Identification System (AIS) data were integrated to identify fishing vessel types and activities. A toolbox in MATLAB and custom algorithms were used to determine frequency-domain metrics within 1/3 octave bands, as suggested by MSFD. Preliminary results indicate that fishing activities contribute significantly to ambient noise, with bottom trawling showing a distinctive acoustic signature. This study demonstrates the efficacy of integrating passive acoustic monitoring with vessel tracking data for assessing the impact of anthropogenic activities on marine ecosystems.