Long-finned pilot whales (Globicephala melas) rely on vocalizations for various biological functions, which further amplifies their sensitivity to anthropogenic noise. Throughout the last half-century, there has been a considerable rise in commercial shipping. Consequently, the ambient low-frequency noise levels across oceans have increased. Utilizing data collected with a bottom-moored autonomous recorder in offshore Irish waters, temporal patterns of pilot whale tonal call detections were analyzed in relation to potential environmental drivers and shipping noise levels. For this purpose, a new protocol for the extraction of G. melas tonal calls was validated with the open-source software PAMGuard. Different Whistle and Moan Detector configuration settings were tested, with no requirement for custom detector training. The resulting habitat modeling outputs revealed an increase in the predicted presence of pilot whales with increasing chlorophyll-a concentration, sea surface current velocity, and during the new moon phase. On the other hand, presence seemed to decrease throughout the day and in response to the increasing proximity of vessels. Despite the low model reliability, this study provided the foundations for further investigation into the impact of shipping noise on this odontocete species. Most importantly, initial guidelines for efficient, accessible, and reliable extraction of G. melas whistles were established.
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