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Recent estimates of blue (Balaenoptera musculus) and humpback (Megaptera novaeangliae) whale ship-strike deaths on the US west coast are above the Potential Biological Removal limit determined by the National Marine Fisheries Service. Beginning in 2015, the National Oceanographic and Atmospheric Administration requested voluntary Vessel Speed Reductions (VSR) in the designated shipping routes off San Francisco, California, USA, in order to decrease whale mortality from ship strikes. We applied a ship strike model based on whale density and Automatic Identification System (AIS) vessel data. We bootstrapped speeds from vessels that transited when no VSR was in place to assess the effect of the VSR on strike mortality rates. Finally, we calculated the expected mortality for hypothetical compliance scenarios by programmatically imposing speed caps. Average predicted mortality for the region was 2.7 blue whales and 7.0 humpback whales in a 4 month period. Compared to years prior to the VSR (2012-2014), vessel speeds during the VSR were slower. This lowered blue whale deaths within the shipping lanes by 11-13% and humpback whale deaths by 9-10% in 2016-2017. If 95% of mariners adhered to recommended 10 knot (kn) limits in the shipping lanes alone, we predicted twice as many blue whale and 3 times as many humpback whale deaths would be avoided relative to current adherence. Adding a 10 kn speed limit (with 95% cooperation) at the ends of each of the lanes would result in about 5- and 4-fold reductions in blue whale and humpback whale mortality, respectively, relative to current practices. Our approach can evaluate ship strikes and mitigation measures for whale populations around the globe.

The continued development of maritime transportation around the world, and increased recognition of the direct and indirect impacts of vessel activities to marine resources, has prompted interest in better understanding vessel operations and their effects on the environment. Such an understanding has been facilitated by Automatic Identification Systems (AIS), a mandatory vessel communication and navigational safety system that was adopted by the International Maritime Organization in 2000 for use in collision avoidance, coastal surveillance, and traffic management. AIS is an effective tool for accomplishing navigational safety goals, and by doing so, can provide critical pre-emptive maritime safety benefits, but also provides a data opportunity with which to understand and help mitigate the impacts of maritime traffic on the marine environment and wildlife. However, AIS was not designed with research or conservation planning in mind, leading to significant challenges in fully benefiting from use of the data for these purposes. We review present experiences using AIS data for strategic conservation applications, and then focus on efforts to ensure archived and real-time AIS data for key variables reflect the best available science (of known limitations and biases). We finish with a suite of recommendations for users of the data and for policy makers. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: To perform magnetic resonance imaging (MRI) scans regarding material parameter and model validation in computational simulations of mechanical interaction of human soft-tissue with body-supporting devices, enhanced medical prognosis in pressure sore prophylaxis, and comfort optimization in automotive and aircraft seating. Materials and Methods: In vivo human gluteal fat and passive muscle tissue material parameters of a volunteer evaluated via combined MRI numerical method and body-supporting foam material parameters employed in finite element (FE) simulations of tissue-support interaction were verified by a defined loading scenario using MRI. MRI of the loaded configurations were performed and compared with simulation results for displacement field information. Results: Deformation of gluteal skin/fat and passive muscle-tissue and support material under interacting loading using numerical simulation complied with the MRI results. Accordance was found for deformed skin surface and internal fat-muscle tissue boundaries by superimposing experimental and numerical outputs. Further evidence of established through in vivo gluteal tissue parameters was thus provided and tissue material isotropy assumption was shown for use in simulated buttock loading interactions. Additionally, a new concept of FE model validation regarding non-MRI-sensitive materials such as polyurethane foam was introduced comprising peripheral surface visualization. Conclusion: Imaging techniques are essential in biomechanical modeling and provide key information regarding model validation and validity assessment. [ABSTRACT FROM AUTHOR]