In situ field measurements of aquatic animal fluid interactions using a Self-Contained Underwater Velocimetry Apparatus (SCUVA)

Kakani Katija,John O. Dabiri

Limnol. Oceanogr. Methods 6:162-171 (2008) | DOI: 10.4319/lom.2008.6.162

ABSTRACT: We describe the development of a Self-Contained Underwater Velocimetry Apparatus (SCUVA) that enables a single SCUBA diver to make in situ digital particle image velocimetry (DPIV) measurements of animal-fluid interactions in real time. The device is demonstrated in a study of the dynamics of Aurelia labiata jellyfish swimming in the coastal waters of Long Beach, California. We analyze the DPIV measurements by computing the kinetic energy in the flow field induced by an animal’s swimming motions. As a proof-of-concept, we compare these results with an existing theoretical model and find that the results are consistent with one another. However, SCUVA provides details regarding the temporal evolution of the energetics during the swimming cycle, unlike the model. These results suggest the usefulness of SCUVA as a method to obtain quantitative field measurements of in situ animal-fluid interactions.