Early Wednesday morning, the Texas Parks and Wildlife Inland Fisheries office in Abilene received reports of dead fish on the banks of Lake Stamford. After arriving on-site, TPWD staff confirmed that an active fish kill is occurring at the lake. Water quality and water samples were taken for analysis to determine the cause.
Golden alga, a microscopic organism that has been linked to other fish kills in The Big Country, was discovered in Stamford earlier this past fall after water samples were taken for analysis. Since the alga was documented, the TPWD staff has been closely monitoring the presence of golden alga in the reservoir. The analysis confirmed that a toxic golden alga bloom is occurring resulting in the fish kill.
The most recent count observation of fish species affected included shad, white bass, freshwater drum, gar, and common carp. However, losses of sunfishes, crappie, catfish and largemouth bass are expected. TPWD staff will continue to monitor the kill by collecting periodic water quality samples and conducting site observations.
For those unfamiliar with golden alga, it typically occurs in marine and brackish environments, but it has been introduced in numerous lakes in the southern and western United States. Causes of golden alga introductions are unknown, but studies suggest the species prefers water bodies that are drought-prone and have higher salinity (i.e., dissolved salts), conductivity (i.e., dissolved ions), and hardness (i.e., mineral content) such as Lake Stamford. During drought, water quality parameters such as salinity increase as water from the lake evaporates, and existing salts become more concentrated, making the water more suitable for golden alga. Once established, golden alga can better use available resources and grow faster than native algae species during the winter and spring. Further, golden alga produces a toxin that prevents fish from up-taking oxygen through their gills, causing them to die of suffocation.
Golden alga is not toxic to people, cattle, dogs or other air-breathing animals. However, people should exercise caution when consuming fish from the lake. Do not eat a fish that looks sick or dead. Healthy-looking, legally caught fish should be safe to eat.
Unfortunately, the only feasible solution to resolve the golden alga problem would be a good rain to return Lake Stamford to a healthy water level. A prolonged hard rain can improve the water quality to where native algae can better compete with golden alga and greatly reduce the toxicity of the golden alga toxin. Until rain comes, Stamford is vulnerable to more golden alga blooms. In the meantime, stay hopeful. Once the water levels return and the lake is non-toxic, your local TPWD fisheries biologists will implement a fisheries recovery plan to restore sport fish and prey species that will include stockings and some habitat management.
You can help prevent golden alga kills by preventing the potential spread. Be sure to follow the steps Clean, Drain, and Dry which can be found at http://www.tpwd.state.tx.us/fishboat/boat/protect_water/ By following these steps, you can prevent the spread of numerous invasive species and potentially golden alga. You can also find ways to conserve and reuse water during periods of drought. For more information about golden alga, please visit http://www.tpwd.state.tx.us/landwater/water/environconcerns/hab/ga/faq.phtml or call your local TPWD fisheries office at (325) 692-0921.