  A 3D copepod trajectory is recorded in the laboratory, using 2 digital
cameras. The copepod undergoes a very structured type of trajectory, with
successive moves displaying intermittent amplitudes. We perform a statistical
analysis of this 3D trajectory using statistical tools developed in the field
of turbulence and anomalous diffusion. We show that the walk belongs to
"multifractal random walks", characterized by a nonlinear moment scaling
function for the distance versus time. To our knowledge, this is the first
experimental study of multifractal anomalous diffusion. We then propose a new
type of stochastic process reproducing these multifractal scaling properties.
This can be directly used for stochastic numerical simulations, and is thus of
important potential applications in the field of animal movement study, and
more generally of anomalous diffusion studies.
