High-resolution acoustic surveys with diving gliders come at a cost of aliasing moving targets

Abstract

Underwater gliders are autonomous robots that follow a slow, see-saw path and may be deployed for months on end. Gliders have a dramatically lower payload capacity than research vessels and are thus limited to more simple instrumentation. They have the advantage, however, of being deployable for long periods of time without the high running costs of a ship. Recent years have seen development of the use of gliders to undertake acoustic surveys of biomass in the pelagic environment, highlighting their potential to fill future survey gaps. Here it is shown, using simulation of sampling, that gliders can resolve acoustic targets at greater resolutions than ships, due to their diving pattern, but that survey accuracy is strongly dependent on the speed of the target.