Baseline hearing abilities and variability in wild beluga whales (Delphinapterus leucas)

• DOI: 10.1242/jeb.093252
• Publication Date: 2014-05-14T21:42:44Z
• Authors: Manuel Castellote; T. Aran Mooney; Lori Quakenbush; Roderick Hobbs; Caroline Goertz; Eric Gaglione
• Keywords: Audiogram; Beluga Whale; Beluga; Bioacoustics; Leucas

While hearing is the primary sensory modality for odontocetes, there are few data addressing variation within a natural population. This work describes ranges (4–150 kHz) and sensitivities of seven apparently healthy, wild beluga whales (Delphinapterus leucas) during population health assessment project that captured released belugas in Bristol Bay, Alaska. The baseline abilities subsequent variations were addressed. Hearing was measured using auditory evoked potentials (AEPs). All audiograms showed typical cetacean U-shape; substantial (>30 dB) found between most least sensitive thresholds. animals heard well, up to at 128 kHz. Two 150 Lowest thresholds (35–45 identified range 45–80 Greatest differences occurred both high end frequencies maximum sensitivity. In general, quite sensitive. similar those zoological settings, reinforcing comparative importance settings. relative degree variability across suggests from multiple individuals needed properly describe sensitivity variance odontocetes. measures easily incorporated into field-based detailed examination Bay provides basis better understanding potential impact anthropogenic noise on noise-sensitive species. Such information may help design noise-limiting mitigation could be applied areas heavily influenced inhabited by endangered belugas.