Visualising the Footprints of Ocean Swimmers

jellyfish-propulsion-480

Photo Credit: National Geographic

Dr Kakani Katija is a bioengineer who works as a postdoctoral fellow at Monterey Bay Aquarium Research Institute (MBARI). Her work involves the study of how marine organisms interact with their environment, more specifically, she studies the fluid interactions that occur as they swim throughout the ocean.

Dr Katija’s species of choice are jellyfish. She is interested on the impact that their movements have on ocean mixing, which involves the movement of water and nutrients from one ocean layer to another.

Any animal that swims creates a wake behind it, these typically consist of vortex rings, spinning masses of water that are created as animals move through the ocean. In her research, Dr Katija studies these wakes through both dye visualisation and a technique known as particle image velocimetry (PIV). PIV involves illuminating particles in the ocean with a laser, and tracking the movement of these particles with a high speed camera as the jellyfish swim through them. From this she is able to quantify the movement of the fluid, calculating specific velocities and masses of fluid as it moves.

Below Dr Katija presents a snapshot of her work in a TED-Ed Original Lesson, giving us an insight into her work and how the study of jellyfish swimming could have big implications in both bio inspired engineering, and our knowledge of how large masses of jellyfish can help drive ocean mixing.