Written by Kendra Davis
A warmer and drier climate can cause an overgrowth of algae in water known as algal blooms that release deadly toxins which kill aquatic life, including fish, birds and mammals, and pose negative effects on the ecosystem.
Algal blooms are caused by an overabundance of simple plants that live in bodies of water. As stated by the Texas Parks and Wildlife Department, the most devastating type of algal bloom in Texas is the Golden Algal Bloom, which was discovered in 1985. This particular bloom killed more than 25 million fish valued at $10 million between 1985 and 2007. Since its discovery in Texas in the Pecos River, it has continued to make its way into 25 of the major river systems throughout the state.
The damaging effects of algal blooms do not stop with aquatic life. Large game animals, such as elk and deer, become poisoned when drinking from lakes or streams that have been infected. In 2013, more than 100 elk became victims to the algal blooms near the Buena Vista Ranch in Las Vegas, New Mexico, killing them within hours after ingesting the water.
A professor with Texas A&M University’s Wildlife and Fisheries program, Dr. Daniel Roelke, has dedicated much of his research to studying the driving factors that cause algal blooms to grow in certain areas and how to manipulate the conditions where the algal blooms are reproducing in hopes that the problem can be mitigated entirely.
“Our most recent studies have shown that phytoplankton made up of species that do not strongly compete against each other suffer more from blooms in comparison to those phytoplankton made up of species that strongly compete against each other,” said Roelke. “The driving force behind the growth of blooms comes from the amount of nitrogen and phosphorus levels in a body of water. If you can manipulate the hydrology in such a way so that these two chemical compounds fluctuate through time, then you can manipulate the systems so that the phytoplankton compete against each other more strongly, thus resulting in less blooms.”
To help support Roelke’s research, Texas A&M Ph.D. student, Rika Muhl, completed a study to appear in the scientific journal Ecology Letters, that focuses on the environmental conditions that can affect phytoplankton.
“Just like humans, phytoplankton need certain resources to survive, such as nitrogen, phosphorus, carbon or vitamins,” said Muhl. “The duration and intensity of harmful algal blooms is reduced when the need for those resources in phytoplankton groups is dissimilar, meaning one phytoplankton may need more nitrogen than another, and vice versa. Therefore, if we can identify and manage environmental conditions that promote healthy and diverse phytoplankton groups, we can create an environment that prevents the reproduction of out-of-control algal blooms.”
The majority of research conducted by scientists from Texas A&M’s Wildlife and Fisheries Department has been performed in lakes in Europe. However, methods are currently being developed and tested that could eventually be used in lakes in the United States and Texas with the use of time series data.
“The harmful algal bloom issue is increasing in frequency and magnitude as we speak, but we hope that the research studies we’ve conducted will bring us closer to mitigating the problem and finding a solution,” said Roelke. “Not only for ecological reasons, but also for the sake of human health.”
A large percentage of the funding for Roelke’s algal bloom research being conducted in Texas comes from agencies interested in combatting the problem, such as U.S. Congress and the Texas Parks and Wildlife Department. Other agencies that are also making efforts to solve water quality issues caused by algal blooms include the Texas Commission on Environmental Quality and the Texas Water Development Board.
To read more about the research regarding the harmful algal bloom issue conducted by Texas A&M Ph.D. student Rika Muhl and Dr. Daniel Roelke, visit Ecology Letters at onlinelibrary.wiley.com/doi/abs/10.1111/ele.13109