Meeting Abstract

81.2  Sunday, Jan. 6  Simultaneous sampling of flow and odorants in a turbulent plume can aid tracking behavior by aquatic organisms PRAVIN, S*; KOEHL, MAR; REIDENBACH, MA; University of Virginia, Charlottesville; University of California, Berkeley; University of Virginia, Charlottesville sp8yh@virginia.edu

Odors are dispersed across aquatic habitats by turbulent water flow as filamentous, intermittent plumes. Many crustaceans take discrete samples of odors by flicking their olfactory antennules. These antennules, in addition to containing chemo-sensors, also contain mechano-sensors that can detect water motion in the surrounding fluid. We examined correlations between fluctuating odorant concentrations and turbulent flow that can provide cues for plume tracking. Laboratory flume experiments utilized a combined planar laser-induced fluorescence (PLIF) and particle image velocimetry (PIV) system to simultaneously measure the flow and odorant concentrations within a turbulent plume. In addition, a numerical model of an odorant release within a boundary layer flow was constructed to simulate the impact of bed geometry and ambient velocity on odorant transport. Results from the laboratory experiments show correlations between high energy eddies and odorants that are actively being stirred, while numerical simulations show that these correlations between flow and odorants change in systematic ways with distance from the source. Detection and use of these correlations by aquatic organisms may enhance tracking efficiency above detection of odorant concentrations or flow alone.