Elongated swimmers in laminar and turbulent flows*

We consider the motion of spheroidal, axisymmetric microorganisms swimming in 

laminar and turbulent flows. 

By means of direct numerical simulations, supported by analytical calculation

in a simplified stochastic setting, we find that in general elongated swimmers

are able to align with the local velocity. 

The preferential swimming direction also produces an accumulation of 

microorganisms with an intensity which depends on the parameters of the flow. 

We discuss the relevance of our results for applications and aquatic ecology.