3D feeding currents of the predatory ctenophore Mnemiopsis leidyi

Lobate ctenophores such as Mnemiopsis leidyi are voracious predators of marine zooplankton, forming critical links in costal and oceanic food. As the global shipping industry has grown over the past century, Mnemiopsis has invaded costal waterways worldwide, unbalancing ecosystems and devastating biodiversity. Mnemiopsis is carnivorous, but not particularly picky in the prey that it consumes. The beating of cilia on the auricles generates a feeding current that is largely hydrodynamically inconspicuous to prey, drawing flow through the lobes and towards the tentillae where slow-moving or sessile prey items are captured. Prey that can perform a fast escape, such as copepods, often attempt to perform an escape after initially coming near to or contacting the lobes. However, Mnemiopsis, sensing the disturbance caused by these larger prey items, is able to close the lobes and surround the prey to prevent its escape. In this study, we present 3D velocity field data on the flows generated by Mnemiopsis during cruising and station-holding in the presence of potential prey. We show how the swimming behaviors of predator and prey can affect predation performance.