Quantitative assessment of invasive species in lacustrine environments through benthic imagery analysis
Limnol. Oceanogr. Methods 10:65-74 (2012) | DOI: 10.4319/lom.2012.10.65
ABSTRACT: The establishment, spread, and impact of the invasive bivalve Corbicula fluminea (C. fluminea), in Lake Tahoe threatens native species distribution in the lake and, potentially, has long-term implications for water clarity. In 2009, UBC-Gavia, an Autonomous Underwater Vehicle (AUV), was used as a platform to collect georeferenced imagery of the benthic regions of Lake Tahoe to determine the lake-wide distribution of C. fluminea. Images were collected in water depths less than 10 m at an approximately constant height above the bottom of 2 m. Images were processed using a semi-automated procedure to determine the ratio of the lakebed covered by exposed C. fluminea shells. A visual review was conducted on a subset of the images to determine presence of filamentous algae that has been observed in association with C. fluminea. Nearly 100 km of shoreline was covered over a 7-d period, and C. fluminea presence was reconfirmed in 4 regions and additional 10 regions identified.