Dear MARMAM, I am pleased to share with you all our paper in Methods in Ecology and Evolution on minimizing the impact of biologging devices. We think that this paper will be of broad interest to marine mammologists and particularly those conducting their research using biologging devices: Kay WP, Naumann DS, Bowen HJ, Withers SJ, Evans BJ, Wilson RP, Stringell TB, Bull JC, Hopkins PW, Börger L (2019) Minimizing the impact of biologging devices: Using computational fluid dynamics for optimizing tag design and positioning. Methods in Ecology and Evolution, 10(8), 1222-1233. URL: https://besjournals.onlinelibrary.wiley.com/doi/full/10.1111/2041-210X.13216 Summary: In this paper we sought to find the best way to minimize the drag of biologging tags. We used Computational Fluid Dynamics (CFD) to model how drag changed with tag size, shape and positioning. Our results showed that improving tag shape is more important than reducing size, suggesting that the persistent aim to ‘miniaturize’ biologging devices may be too simplistic. We also observed that having a hydrodynamic design can reduce the effect of positioning on tag-induced drag. This is important as it is of course not always possible to place a device in the optimum position on an animal with respect to minimizing drag. We also provide a step-by-step guide for ecologists to repeat our method and we hope this will encourage future partnerships. There is also an associated blog piece, published yesterday, which provides a more informal overview of the work. You can find this here: https://methodsblog.com/2019/09/10/biologging-cfd/ For any correspondence, please email: william.p.kay@swansea.ac.uk<mailto:william.p.kay@swansea.ac.uk>. Best, William Kay and co-authors