W. Rodney, Texas Parks and Wildlife Department, Galveston, TX, USAE. Munday, BioSonics, Inc., Seattle WA, USA
Abstract A new hydroacoustic processing software (BioSonics Visual Habitat) for the rapid assessment and mapping of various substrate types (sand, cobble, mud, etc.) was recently evaluated using data collected by researchers at Texas Parks and Wildlife Department (TPWD) as a means to quantify and map oyster reefs. Understanding the distribution of oyster reef habitats is vital in guiding restoration and management efforts. Obtaining quantifiable data on oyster reef resources is important in establishing a baseline for future surveys and developing an index for monitoring temporal changes. The study area is a 5.7 sq km rectangular grid of 10 transects spaced 200 m apart. Hydroacoustic data collected from the study area were processed and the results were plotted over side scan sonar imagery. Visual Habitat was compared with two previously existing processing tools; QTC Impact, BioSonics VBT, and a TPWD proprietary SAS method. The results from Visual Habitat showed a high agreement with prior results and resulted in a significant reduction in effort as compared to processing with other software. In addition to the significant reduction in effort, Visual Habitat provided data visualization tools in the form of a transect map view displaying user-defined color gradients for each data layer. Visual Habitat also provides the ability to export results in KML file format for rapid interpretation via Google Earth.