LSU’s College of the Coast & Environment Partners with New Taskforce to Improve Information about Louisiana’s Harmful Algal Blooms
Infographic of good v.s. bad algae created by Emily Smith and Sibel Bargu in LSU's
College of the Coast & Environment.
Photo Credit
February 13, 2020
BATON ROUGE – LSU’s College of the Coast & Environment, or CC&E, LSU’s College of Science, and the Lake Pontchartrain Basin Foundation have created the Harmful Algal Bloom, or HAB, Taskforce, to share the latest research on harmful algal blooms in Lake Pontchartrain and other Louisiana ecosystems and to prepare stakeholders for future HAB occurrences. Harmful algal blooms can severely affect human health and aquatic ecosystems and can create or exacerbate low oxygen zones, or dead zones, such as the Gulf of Mexico dead zone.
According to Sibel Bargu, associate dean of academics, professor, and CC&E’s HAB expert, “The HAB Task Force’s inaugural meeting, for the first time, brought many government agencies and local researchers together to share information, discuss the increase in HAB occurrences, and determine the actions that must be taken to disseminate information to the public in a timely manner.”
Bargu, who has been monitoring HABs that occurred in Lake Pontchartrain in the wake of each Bonnet Carré Spillway opening since 2008, says that the presence of algae does not always indicate that there will be toxins in the water. Identifying the species of algae—and their potential toxicity—matters; however, the higher the abundance of algae, the higher the likelihood that it will be harmful. Different species have different thresholds for when their abundance rises to the classification of “harmful and/or toxic,” and some species can release more than one type of toxin. Several scientists at the task force meeting warned that HAB occurrences were increasing because of increased nutrient loads, rising water temperatures, and disruptions of salinity levels.
Task force members also discussed advancements in HAB monitoring. Chunyan Li, Mobil Distinguished Professor of Marine Geology in CC&E’s Department of Oceanography & Coastal Sciences and an expert in hydrodynamics who has conducted research in Lake Pontchartrain since 2005, discussed his recent research project developing a model that could predict how river flow, wind, and severe weather affect freshwater plumes and residence time in the lake during a Bonnet Carré Spillway opening.
The spillway is made up of a series of bays, or gates, that are opened when the river is high to release excess floodwater from the Mississippi River into the lake and, from there, into the Gulf of Mexico; however, if the water level is high enough, river water can flow through gaps in the bays and into the lake long before the spillway is opened. Li’s team uses their model to demonstrate the significant effects of the leakage on the lake’s salinity after the opening. This leakage effect on salinity was also found to be significantly influenced by the variation of wind speed and direction. His team also conducted surveys of the spillway to measure water flow velocity and salinity in and out of the plume, and quantified the total discharge at the Bonnet Carré Spillway.
Whenever an HAB occurs in Lake Pontchartrain or along the Louisiana Coast, the public is often concerned about whether it is safe to swim or eat seafood from the affected areas. The HAB Task Force will collaborate on their research and monitoring efforts and coordinate communications with the public to provide accurate, comprehensive assessments as quickly as possible during future HAB occurrences.
This task force meeting included scientists from LSU, Tulane, and University of Louisiana at Lafayette. Government agencies participating in the meeting included the Louisiana Department of Environmental Quality, Louisiana Department of Health, Louisiana Sea Grant, Coastal Protection and Restoration Authority, Lake Pontchartrain Basin Foundation, the Water Institute of the Gulf, U.S. Geological Survey, United States Army Corps of Engineers, U.S. Environmental Protection Agency, and National Oceanic and Atmospheric Administration.
Contact Christine Wendling
LSU College of the Coast & Environment
225-578-4984