We are pleased to announce the publication of a short review that summarizes our current ideas how sonar may interfere with diving in cetaceans. This article is an open access publication, which means that it is freely accessible to any reader anywhere in the world. We encourage you to share the article link with any colleagues who may be interested in this work. ** * Title: * How man-made interference might cause gas bubble emboli in deep diving whales* *Authors: **Andreas Fahlman, Peter L Tyack, Patrick James Miller, and Petter H Kvadsheim **Journal: **Frontiers in Physiology** URL: **http://www.frontiersin.org/Journal/Abstract.aspx?f=65&name=physiology&ART_DO... **** *Abstract**: * Recent cetacean mass strandings in close temporal and spatial association with sonar activity has raised the concern that anthropogenic sound may harm breath-hold diving marine mammals. Necropsy results of the stranded whales have shown evidence of bubbles in the tissues, similar to those in human divers suffering from decompression sickness (DCS). It has been proposed that changes in behavior or physiological responses during diving could increase tissue and blood N_2 levels, thereby increasing DCS risk. Dive data recorded from sperm, killer, long-finned pilot, Blainville's beaked and Cuvier's beaked whales before and during exposure to low- (1-2 kHz) and mid- (2-7 kHz) frequency active sonar were used to estimate the changes in blood and tissue N_2 tension (P_N2 ). Our objectives were to determine if differences in 1) dive behavior or 2) physiological responses to sonar are plausible risk factors for bubble formation. The theoretical estimates indicate that all species may experience high N_2 levels. However, unexpectedly, deep diving generally result in higher end-dive P_N2 as compared with shallow diving. In this focused review we focus on three possible explanations: 1) We revisit an old hypothesis that CO_2 , because of its much higher diffusivity, forms bubble precursors that continue to grow in N_2 supersaturated tissues. Such a mechanism would be less dependent on the alveolar collapse depth but affected by elevated levels of CO_2 following a burst of activity during sonar exposure. 2)_During deep dives, a greater duration of time might be spent at depths where gas exchange continues as compared with shallow dives. The resulting elevated levels of N_2 in deep diving whales might also make them more susceptible to anthropogenic disturbances. 3) Extended duration of dives even at depths beyond where the alveoli collapse could result in slow continuous accumulation of N_2 in the adipose tissues that eventually becomes a liability.** *Citation:* Fahlman A, Tyack PL, Miller PJO and Kvadsheim PH (2014) How man-made interference might cause gas bubble emboli in deep diving whales./Front. Physiol/.*5*:13. doi: 10.3389/fphys.2014.00013 -- Andreas Fahlman Department of Life Sciences Texas A&M- Corpus Christi 6300 Ocean Dr Unit 5892 Corpus Christi, TX 78412 Ph. +1-361-825-3489 Fax +1-361-825-2025 mail: andreas.fahlman@tamucc.edu web: http://www.comparative-physiology.tamucc.edu/