Sunlight To Ease Algae Caused Fishkill

Researchers from Baylor University state that although golden algae is primarily a coastal species, it has been found in Texas rivers and lakes, including Lake Whitney and Lake Waco in Central Texas, and Lake Granbury in North Texas.

The new research from Baylor University scientists has now shown that sunlight is a key component in the magnitude and duration of the toxicity of the algae to fish.

Specifically, the study highlighted that the longer golden algae toxins were exposed to natural sunlight, the less toxic they became to fish and other aquatic organisms.

"What we think happens in terms of the large fish kills is that sunlight only penetrates down so deep in a lake, so in a lake with golden algae blooms, fish located at greater depths may be exposed to more algal toxins," said study co-author Dr Bryan Brooks, associate professor of environmental sciences and biomedical studies at Baylor and director of the environmental health sciences programme.

"Golden algae is aggressive and very unique because it can produce its own toxins, swim, photosynthesise and feed on other organisms. If we can figure out what stimulates and decreases the growth of this algae, we might be able to control it," he concluded.

Along the Brazos River in north and central Texas, at least seven million fish have been killed since 1988 due to high golden algae levels, according to Texas Parks and Wildlife.

In 2005 more than a million fish died in Lake Whitney over a three month period. Officials again believe that large golden algae blooms contributed to the deaths, attacking the fishes' gills and causing them to suffocate.

Scientists from the University of Texas at Arlington and Texas A&M also contributed to the study. The study funded through a grant from the Texas Parks and Wildlife Department.

The study can be found online at the Journal of Plankton Research.