Extended duration acoustic tags provide insight into variation in behavioral response to noise by marine mammals

Current estimates of the population level effects of noise exposure rely on model predictions to link exposures to health and vital rates. While noise exposure levels can be accurately modelled for controlled signal production, it is challenging to estimate the effects of cumulative noise exposure from multiple noise sources in the environment. In the wild, variation in background noise levels and in the motivational state of individual animals will impact their responsiveness to noise. Data collected over longer, more biologically relevant, time scales of weeks to months will improve our understanding of the variability in noise exposure and behavioral responsiveness of marine mammals. This study explores our ongoing work to extend the duration of fine-scale acoustic and movement tag data to explore these questions. Using data from humpback whales (Megaptera novaengliae) and manatees (Trichechus manatus latirostris), we demonstrate individual variability in behavior and noise exposure scaling from diel trends from a two day tag from a whale and spatial variability from a 44 day continuous manatee tag record. This study highlights the value of longer-term fine-scale data to better inform model predictions for disturbance to address challenging questions related to the cumulative impact of noise-induced behavioral responses on individual health.