  Tracks of marine animals in the wild, now increasingly acquired by electronic
tagging of individuals, are of prime interest not only to identify habitats and
high-risk areas, but also to gain detailed information about the behaviour of
these animals. Using recent satellite-derived current estimates and leatherback
turtle (Dermochelys coriacea) tracking data, we demonstrate that oceanic
currents, usually neglected when analysing tracking data, can substantially
distort the observed trajectories. Consequently, this will affect several
important results deduced from the analysis of tracking data, such as the
evaluation of the orientation skills and the energy budget of animals or the
identification of foraging areas. We conclude that currents should be
systematically taken into account to ensure the unbiased interpretation of
tracking data, which now play a major role in marine conservation biology.
