Predictions of animal exposure to anthropogenic acoustic sources have become increasingly sophisticated through simulating animal behavior. A long-standing issue has been the question of how many exposures occur during an activity and how those exposures are distributed over individual animals. A sensitivity study evaluated the effects of simulation duration, source movement, animal movement and group size. Two airgun array survey patterns (2D and 3D) were modeled, each with a one-month duration. During each simulation, animal movement was modeled for low-frequency, shallow and deep diving mid-frequency, and high-frequency cetaceans. The unweighted 160 dB RMS exposure threshold for behavior was used to evaluate the effect of different modeling parameters. Results found that simulating animals in groups does not alter the predicted level of exposure, but it does increase its variance. Examining the full 30 day exposure records found that deeper divers had a greater number of exposures. The more wide-ranging 2D survey pattern exposed more individual animals and animals had fewer multiple exposures than the 3D survey pattern. Species with higher residencies had a greater number of multiple exposures. Finally the long-duration modeling provides an explicit ability to predict the number of exposed individuals rather than just the number of exposure events.

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