Multi-scale Characterization of Mesopelagic Organisms including Three-dimensional Imaging Lidar

Life in the ocean’s mesopelagic zone is largely uncharacterized despite its vital role to ocean ecosystems. While more recent studies suggest the biomass of this region may be tenfold greater than previously estimated, we still lack an integrative multi-scale understanding of organism migration patterns, distribution and diversity in this transport region. NOAA Cooperative Institute for Ocean Exploration, Research and Technology (CIOERT) based at Harbor Branch Oceanographic Center tackles this problem by combining complimentary technologies with overlapping size spectrums that captures a connected interaction between multiple species. These technologies include a combination of profiler and ship mounted acoustic devices and novel instruments such as a, Spatial PLankton Analysis Technique (SPLAT) bioluminescence imaging system and an Unobtrusive Multi-Static Lidar Imager (UMSLI). This unique sensor compilation creates opportunity to observe distribution patterns at an extended range, as well measures less commonly quantified size ranges from millimeters to centimeters. UMSLI observes a dynamic range of organisms across an expanding volume using three-dimensional photo-realistic laser serial imaging. Its imaging rectifying ability allows for identification of large fish species, calculation of particle concentrations and flux measurements and size distribution metrics. This presentation promotes the advantages of lidar imaging in discussion with post processing signal enhancement methods and will focus on UMSLI’s results and connectivity to other measurements. We also present a quantitative data synthesis for this unique exploration system and demonstrate the importance of an integrated approach to studying organism dynamics in this environment.