Optimization of Towed Passive Acoustic Monitoring Array Design and Performance Study

Publication Title: Optimization of Towed Passive Acoustic Monitoring Array Design and Performance Study

Subject: Anthropogenic Properties
Passive acoustic monitoring; mitigation; numerical model; algorithm; offshore renewable energy

CSE Reference: Thode A, Abadie S, Barkaszi MJ (CSA Ocean Science Inc., Stuart, FL). 2021. Optimization of towed passive acoustic monitoring array design and performance study. Sterling (VA): US Department of the Interior, Bureau of Ocean Energy Management. 4 p. Obligation No.: M0119F0051. Report No.: OCS Study BOEM 2021-086. URL: https://espis.boem.gov/Technical%20Summaries/BOEM_2021-086.pdf

Abstract: A numerical model for simulating the localization performance of a three- or four-hydrophone towed passive acoustic monitoring (PAM) array on multiple species clusters has been developed that allows the Bureau of Ocean Energy Management (BOEM) to assess the localization efficacy of towed PAM arrays proposed in mitigation and monitoring plans for offshore wind farm development and other operations. Simulations of a 200-m aperture array were run for three marine mammal signal types of interest: sperm whale, right whale, and beaked whale. The ability to localize a marine mammal call using PAM systems commonly deployed for mitigation surveys conducted in support of offshore wind farm development requires several conditions and assumptions. In order to localize, the call must first be detected. A detection’s range will be dictated by the received amplitude of the signal, which in turn depends on the species, distance, and relative orientation to the receiver, as well as the noise conditions of the monitoring environment. The goal of this project was the development of an algorithm and user interface with the intent to enable BOEM personnel to input proposed array specifications and determine the theoretical localization capability for low-, mid-, and high-frequency cetaceans within 5 km of the array.