Dear Colleagues, The following paper was recently published in the Journal of the Acoustical Society of America, and is available as an open access article here: https://asa.scitation.org/doi/full/10.1121/10.0004817 Near real-time detection of low-frequency baleen whale calls from an autonomous surface vehicle: implementation, evaluation, and remaining challenges Mark Baumgartner, Keenan Ball, Jim Partan, Léo-Paul Pelletier, Julianne Bonnell, Cara Hotchkin, Peter Corkeron, and Sofie Van Parijs Mitigation of threats posed to marine mammals by human activities can be greatly improved with a better understanding of animal occurrence in real time. Recent advancements have enabled low-power passive acoustic systems to be integrated into long-endurance autonomous platforms for persistent near real-time monitoring of marine mammals via the sounds they produce. Here, the integration of a passive acoustic instrument capable of real-time detection and classification of low-frequency (LF) tonal sounds with a Liquid Robotics wave glider is reported. The goal of the integration was to enable monitoring of LF calls produced by baleen whales over periods of several months. Mechanical noises produced by the platform were significantly reduced by lubricating moving parts with polytetrafluoroethylene, incorporating rubber and springs to decelerate moving parts and shock mounting hydrophones. Flow noise was reduced with the development of a 21-element hydrophone array. Surface noise produced by breaking waves was not mitigated despite experimentation with baffles. Compared to a well-characterized moored passive acoustic monitoring buoy, the system greatly underestimated the occurrence of sei, fin, and North Atlantic right whales during a 37-d deployment, and therefore is not suitable in its current configuration for use in scientific or management applications for these species at this time. If you are interested in near real-time acoustic detection of baleen whales from autonomous platforms, you may be interested in 2 additional open-access papers that evaluate the same real-time acoustic monitoring system in moored buoys and Slocum gliders: Baumgartner. M.F., J. Bonnell, S.M. Van Parijs, P.J. Corkeron, C. Hotchkin, K. Ball, L.-P. Pelletier, J. Partan, D. Peters, J. Kemp, J. Pietro, K. Newhall, A. Stokes, T.V.N. Cole, E. Quintana, and S.D. Kraus. 2019. Persistent near real-time passive acoustic monitoring for baleen whales from a moored buoy: system description and evaluation. Methods in Ecology and Evolution 10:1476–1489, doi: 10.1111/2041-210X.13244. Available at https://besjournals.onlinelibrary.wiley.com/doi/10.1111/2041-210X.13244. Baumgartner, M.F., J. Bonnell, P.J. Corkeron, S.M. Van Parijs, C. Hotchkin, B.A. Hodges, J. Bort Thornton, B.L. Mensi and S.M. Bruner. 2020. Slocum gliders provide accurate near real-time estimates of baleen whale presence from human-reviewed passive acoustic detection information. Frontiers in Marine Science 7:100, doi: 10.3389/fmars.2020.00100. Available at https://www.frontiersin.org/articles/10.3389/fmars.2020.00100/full. Mark Baumgartner Senior Scientist Biology Department Woods Hole Oceanographic Institution MS #33, Redfield 256 266 Woods Hole Road Woods Hole, MA 02543 mbaumgartner@whoi.edu <mailto:mbaumgartner@whoi.edu> www.whoi.edu/sites/mbaumgartner <http://www.whoi.edu/sites/mbaumgartner> (508) 289-2678 phone