Water Resources Research Act Program

Details for Project ID 2019LA119B

Assessing present and potential effects of cyanotoxins in south Louisiana estuaries

Institute: Louisiana
Year Established: 2019 Start Date: 2019-03-01 End Date: 2020-02-29
Total Federal Funds: $9,168 Total Non-Federal Funds: $18,336

Principal Investigators: Beth A. Stauffer

Abstract: Cyanobacteria are natural components of diverse phytoplankton food webs in all aquatic ecosystems. However, a number of harmful algal bloom (HAB) species of cyanobacteria predominantly found in freshwaters systems produce toxins (cyanotoxins) with a range of effects, including causing damage to organs (e.g. liver, kidneys), nervous systems, and fundamental metabolic processes (e.g. protein synthesis). The causes of cyanobacteria blooms and their associated cyanotoxins are the focus of ongoing research in freshwater systems due to their significant impacts on drinking water safety. However, many toxic cyanobacteria species are also able to persist in low salinity waters found in estuarine coastal areas common to Louisiana. The proposed research seeks to quantitatively assess present and potential future presence of cyanobacteria and the toxins they produce in estuarine waters of south Louisiana. As such, the research is focused on understanding water quality, toxic substances, and the ecology of nearshore and estuarine phytoplankton communities. Given the potential for cyanobacteria and their toxins to become more prevalent with ongoing restoration, climate change, and nutrient loadings, the proposed research also seeks to address potential risks of freshwater diversions in the State’s estuaries. In order to assess the present and potential effects of cyanotoxins on south Louisiana estuaries, the proposed research will address three main objectives: Objective 1) Quantify microcystin, anatoxin, and cylindrospermopsin concentrations along gradients representing river-influence in the Atchafalaya-Teche/Vermilion Basin (AVTB) estuarine system, an economically- and ecologically-important estuary in which no cyanotoxin assessments have been undertaken; Objective 2) Relate cyanotoxin concentrations to environmental predictors such as salinity, temperature, and nutrient availability in the system; Objective 3) Share these data with stakeholders in restoration and management of south Louisiana estuaries and coastal land. Current and new study sites in Vermilion and West Cote Blanche Bays will be targeted for cyanotoxin quantification by both point sampling (via shore-based and small boat field collections) and time-integrated, passive toxin monitoring devices (Solid phase adsorption toxin tracking [SPATT] bags deployed from hardened structures in the bays). The AVTB The proposed research builds off of ongoing projects in the Stauffer Lab at UL Lafayette and will provide training opportunities for one Ph.D. student and at least one undergraduate researcher. Results will allow for both the assessment of current prevalence of cyanotoxins in a network of important estuaries and for the prediction for how restoration-driven freshening of other Louisiana estuaries (and coastal waters, more generally) may lead to enhanced cyanotoxin presence and impacts. Results will be shared with stakeholders (e.g. Louisiana Dept. of Wildlife and Fisheries, The Water Institute of the Gulf, Environmental Defense Fund Sediment Diversion Operations Working Group, Louisiana Sea Grant, and others) via “onepager†documents summarizing results, presentations at local and regional conferences and workshops, and publication of scientific findings.