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Abstract Sea turtle stranding events provide an opportunity to study drivers of mortality, but causes of strandings are poorly understood. A general sea turtle carcass oceanographic drift model was developed to estimate likely mortality locations from coastal sea turtle stranding records. Key model advancements include realistic direct wind forcing on carcasses, temperature driven carcass decomposition and the development of mortality location predictions for individual strandings. We applied this model to 2009–2014 stranding events within the Chesapeake Bay, Virginia. Predicted origin of vessel strike strandings were compared to commercial vessel data, and potential hazardous turtle-vessel interactions were identified in the southeastern Bay and James River. Commercial fishing activity of gear types with known sea turtle interactions were compared to predicted mortality locations for stranded turtles with suggested fisheries-induced mortality. Probable mortality locations for these strandings varied seasonally, with two distinct areas in the southwest and southeast portions of the lower Bay. Spatial overlap was noted between potential mortality locations and gillnet, seine, pot, and pound net fisheries, providing important information for focusing future research on mitigating conflict between sea turtles and human activities. Our ability to quantitatively assess spatial and temporal overlap between sea turtle mortality and human uses of the habitat were hindered by the low resolution of human use datasets, especially those for recreational vessel and commercial fishing gear distributions. This study highlights the importance of addressing these data gaps and provides a meaningful conservation tool that can be applied to stranding data of sea turtles and other marine megafauna worldwide. Highlights • Development of a general turtle carcass oceanographic drift model • Improvement in our ability to predict sea turtle mortality from stranding data • Identified potential locations of hazardous turtle-human interactions in Virginia • Quantitative assessments hindered by the low resolutions of human use datasets [ABSTRACT FROM AUTHOR]

There have been several incidents in which U.S. Navy sonar operations at sea coincided in time and location with a mass stranding of marine mammals, particularly beaked whales. Although a conclusive cause-and-effect relationship has not been established, there is strong evidence and scientific concern that use of military sonar has resulted in beaked whale mass strandings. Most previous attempts to determine whether military sonar use and whale strandings are correlated have looked at mass stranding records of beaked whales and have singled out those instances in which military operations appear to coincide in time and location with a mass stranding event. In this study, historical data on beaked whale mass strandings and military exercises that were likely to include active sonar use were compiled, and statistical analyses were performed to determine the level of correlation between these events for four geographic regions. Strandings were significantly correlated with naval activity in the Mediterranean and Caribbean Seas, but not off the coasts of Japan and southern California. [ABSTRACT FROM AUTHOR]

The article discusses the BP oil spill in the Gulf of Mexico and environmental forensics being conducted to determine its role in beach strandings and deaths of marine life including dolphins and sea turtles. The U.S. National Oceanic and Atmospheric Administration (NOAA) is noted for its central role in saving stranded animals and in collecting evidence for a National Resource Damage Assessment (NRDA).