Expanded molecular, biochemical, and statistical analyses of a 2019 toxic cyanobacterial proliferation event in Lady Bird Lake, Austin, Texas

Multiple canine deaths and illnesses were reported in the summer of 2019 after dogs swam in the nearshore waters of Red Bud Isle (RBI), an off-leash dog park located on Lady Bird Lake, Austin, Texas. Lady Bird Lake, the last in-line impoundment of the Texas Colorado River in the heart of downtown Austin, is a central attraction to residents, providing miles of hike and bike trails, and pet-friendly parks. Thick cyanobacterial proliferations, arising from the benthos, floating at the surface around RBI were first documented on August 3rd, 2019. Metaphyton mat samples were collected from selected sites starting in August 2019 and concluding in November 2019, when the mats dissipated. Mats and water samples were analyzed for cyanobacterial composition and water quality parameters. Micrographs of intact mats and isolates were documented. Cyanobacterial communities were isolated to unialgal cultures for subsequent DNA isolation for 16S and 23S rRNA barcode sequencing for identification. Targeted toxins were analyzed using RP-HPLC-MS from metaphyton materials. Ordination analyses of water quality conditions during the period of toxic mat presence and the previous 3-year period were carried out to visualize differences in parameters; a direct comparison of water quality concentrations was then applied to confirm what was significantly different during the proliferation period. The following dataset includes raw and processed HPLC data, raw and processed sequencing data, raw data used for the Pearson Correlation non-metric multidimensional scaling (NMDS) analysis, and additional micrographs; results are published in Perri et al. 2024.