Dear All Sorry for any cross-listing but this may be of general interest to this community and is a new paper using acceleration to estimate energy use: "Estimates for energy expenditure in free-living animals using acceleration proxies; a reappraisal": Wilson, R.P., Börger, L., Holton, M.D., Scantlebury, D.M., Gómez-Laich, A., Quintana, F., et al. (2019). Estimates for energy expenditure in free-living animals using acceleration proxies; a reappraisal. Journal of Animal Ecology, 1-12. doi: 10.1111/1365-2656.13040. ABSTRACT 1. It is fundamentally important for many animal ecologists to quantify the costs of animal activities, although it is not straightforward to do so. The recording of triaxial acceleration by animal‐attached devices has been proposed as a way forward for this, with the specific suggestion that dynamic body acceleration (DBA) be used as a proxy for movement‐based power. 2. Dynamic body acceleration has now been validated frequently, both in the laboratory and in the field, although the literature still shows that some aspects of DBA theory and practice are misunderstood. Here, we examine the theory behind DBA and employ modelling approaches to assess factors that affect the link between DBA and energy expenditure, from the deployment of the tag, through to the calibration of DBA with energy use in laboratory and field settings. 3. Using data from a range of species and movement modes, we illustrate that vectorial and additive DBA metrics are proportional to each other. Either can be used as a proxy for energy and summed to estimate total energy expended over a given period, or divided by time to give a proxy for movement‐related metabolic power. Nonetheless, we highlight how the ability of DBA to predict metabolic rate declines as the contribution of non‐movement‐related factors, such as heat production, increases. If you have any questions or would like a pdf copy of the article, please do not hesitate to contact me at afahlman@whoi.edu <mailto:afahlman@whoi.edu> Sincerely Andreas