Passive Acoustic Monitoring of Fin Whales (Balaenoptera physalus) Near Offshore Wind Farm Areas Off the Coast of New Jersey

Abstract

Increased interest in renewable energy has led to recent development of offshore wind energy; however, very little is known about the impacts that construction of wind farms may have on the maritime environment along the U.S. east coast. Large baleen whales are of particular concern due to limited knowledge of their populations, hearing abilities, and responses to human activity. This study explores the occurrence of fin whales by processing approximately nine months of acoustic data from 2008 collected by Marine Autonomous Recording Units off the coast of New Jersey that were located in what is now wind energy lease areas. Machine learning using automated detectors captured data from acoustic events, and visual confirmations of spectrograms were used in the analysis. The times with most presence and greatest quantity of vocalizations were during the late summer to the middle fall and from 10 a.m. to 1 p.m., respectively. The Automatic Identification System data from cargo ships in 2009 and 2019 were analyzed to help provide understanding of the potential acoustic detection ranges and masking of the recording units. The results from this study give insight to the population of fin whales, and their presence and call patterns can be used for wind farm construction recommendations and other forms of ocean construction that may impact the species while also providing a baseline for future studies.