..., and accelerometry to validate dynamic body acceleration as a proxy measure for field metabolic rate. Field metabolic rate Daily activity patterns Flight costs Accelerometry Doubly labelled water Natural Sciences and Engineering Research Council of Canada http://dx.doi.org/10.13039/501100000038...

... was funded by institutional budgets from the Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany. * Author for correspondence ( [email protected] ) 15 6 2012 29 8 2012 © 2012. 2012 Chiroptera energetics flight costs running costs vertebrate flight...

...). This difference may at least partly be due to the shorter wings of the juveniles tested in the wind tunnel during autumn. However, it seems unlikely that this can account for all of the large difference. It is suggested that wind tunnel experiments might overestimate birds' flight costs compared with free flight...