Blue-green algae blooms remain in the Manatee River. Could help be on the way?

The Florida Department of Environmental Protection has increased the number of sampling sites along the Manatee River and in Robinson Preserve after previous testing showed the formation of blue-green algae blooms.

DEP tested 25 sites from June 28 through July 4, noting that conditions in the river seem to be improving with one notable exception.

“The Manatee River conditions have improved with no new reports,” the DEP’s weekly report states. “DEP staff report that conditions look much better except in the Bradenton area where staff were scheduling a sampling event for next week.”

Of the 25 sites tested, 17 were reported to have a bloom present and three of those 17 sites were in the Braden River. Most of the sites that tested positive were in the Bradenton area corridor of the river on both the north and south banks.

The good news is that Robinson Preserve is testing free of cyanobacteria, the bacteria responsible for blue-green algae. Algae blooms began being reported on June 24 along with a species of filamentous cyanobacterium that were clogging up waterways and causing a, “mucky mess,” Manatee County Parks and Natural Resources Director Charlie Hunsicker said on July 1.

Hunsicker said it was worse this year because of last summer’s devastating red tide event. The county took action by moving the dead algae pads to where they could be pulled by the tide from the preserve and put up a barrier to keep it from reentering the preserve. The water was already beginning to clear when U.S. Rep. Vern Buchanan, R-Longboat Key visited on July 1.

Waters around Anna Maria Island remain clear from blue-green algae, which includes Palma Sola Bay and Perico Bayou.

Could pitting virus vs. bacteria be the solution?

Scientists at Florida Gulf Coast University say they are inching closer to a solution to the blue-green algae problem by using a type of virus to fight the bacteria that forms the blue-green algae.

According to Florida Today, FGCU virologist professor Sharon Isern and her team are working to isolate a naturally occurring bacteria-killing virus known as phage.

Phage is the most abundant organism on earth and is equally diverse. So, Isern said the trick is to find the specific phage that will have the desired impact on cyanobacteria and to treat the “patch” before it becomes the “bloom.”

The use of phage against bacteria is nothing new and was the go-to treatment against bacterial illnesses in humans before the development of antibiotics.

“The impetus of using phage therapy — using viruses that can control and sometimes kill the bacteria — that research got sidelined because we had antibiotics,” Isern told Florida Today.

Phage is making a comeback as some bacteria develop a resistance to antibiotics and it’s proving successful, so, “Why not explore its potential for curing the environmental ills as well?” Isern said.

Phage is perfectly safe to humans and scientists wouldn’t have to introduce the kind of chemicals that are being tested now to battle both blue-green algae and Karenia brevis, the organism responsible for red tide. However, phage would not be effective against Karena brevis because it is not a bacteria.

Isern said phage is already in the water so it’s not being introduced, it’s just a matter of isolating the ones that are already doing what they do naturally. That is the current focus of her team.

Not everyone is confident it will work. University of Miami professor and algae scientist Larry Brand told Florida Today that it’s an attractive idea, but not without challenges. Brand explained that the phage will have success with its specific target but that blooms have enough genetic diversity to where it won’t kill off an entire bloom.

This story was originally published July 8, 2019 at 10:51 AM.