Humans are making red tide blooms much worse. There’s one way to stop it, professor says

Suncoast Waterkeeper is non-profit that takes on environmental issues facing Southwest Florida through community education, fieldwork, advocacy and, occasionally, legal action.

Each year at Brunch for the Bay, the group invites a guest to speak directly to community members about an issue facing the region.

This year, no issue was more timely than red tide.

The event was held on Sunday at the Bradenton Yacht Club in Palmetto, and the group invited University of Miami professor Larry Brand to present his research on harmful algal blooms.

Brand is a professor of Marine Biology and Ecology at the Rosenstiel School of Marine and Atmospheric Science at UM.

In 2007, he published research with colleague Angela Compton that attributes a long-term increase in red tide severity directly to human activity. The study made use of date collected by the Florida Fish and Wildlife Research Institute from 1994 to 2002.

Brand and Compton’s conclusions are in direct contrast with other prominent red tide researchers in the state of Florida, including Mote Marine Laboratory and the Florida Fish and Wildlife Commission.

Both Mote Marine Lab and FWC claim that there is no direct evidence linking nutrient pollution with the frequency or start of red tide blooms.

Brand disagrees with how they are interpreting the data.

The culprit behind intense harmful algal blooms, Brand says, is nutrient overload in state waters due to human activity. Brand says that the nutrients that cause extreme red tide blooms are carried to Florida’s west coast from Lake Okeechobee via the Caloosahatchee River.

Harmful algal blooms aren’t just a Florida problem. The issue is popping up all over the world.

“We’re having to feed seven and half billion people on this planet now,” Brand said. “That takes a lot of food. That takes a lot of nutrients. The two major nutrients you need are nitrogen and phosphorous.”

Those same nutrients will feed algal blooms when out of proportion, Brand explained.

“When you fertilize your crops, you’re not 100 percent efficient. Basically the algae need the same exact nutrients as the higher plants do on land. So you have this runoff of these nutrients and you generate algal blooms.”

Florida’s natural geology also comes into play.

Phosphate deposits on the west coast enrich waters with phosphorous, while limestone-dominated east coast waters are richer in nitrogen. The balance is thrown further out of whack by the extra nutrients, allowing harmful algal blooms to thrive.

In addition to runoff from farmlands, Brand says that the drainage and rerouting of Florida’s waterways has caused natural nutrient deposits buried over thousands of years to become exposed.

Nutrient pollution and subsequent harmful algal blooms have dramatically increased since the government started subsidizing the sugar industry in the 1950s, Brand says.

“They continue to subsidize the sugar industry to the tune of maybe two to five billion a year,” Brand said. “Well, basically I was pointing out a correlation between the algal blooms in Florida Bay and sugar cane farms and a lot of people were very displeased with that. Some scientists that got a lot of curious money, millions of dollars, came up with the conclusion that there actually was no correlation between the algal blooms in Florida Bay and runoff from the north.”

Brand says state researchers used sample data from areas where no algal blooms were occurring in order to support a theory that agriculture runoff was not impacting water quality.

In Brand’s view, the only way to stop the problem is by cutting off the supply of nutrients and allowing the state’s waters to flow naturally once again.

Brand says there is a reason that red tide does not occur every year, but scientists aren’t sure what that is yet.

“You get an algal bloom every year,” Brand said. “But it’s not always red tide. Some years it’s non-toxic algae. What you have is all of these different species of algae competing with each other for these nutrients that are coming down the river. Some years red tide wins out; some years it’s some other species. That’s the part we don’t understand yet. We can’t predict it very well.”

As research continues, Suncoast Waterkeeper is putting pressure on local and state government to make water policy changes now.

The group sued the city of St. Petersburg in 2016 for releasing sewage in Tampa Bay and successfully reached a settlement.

The group is seeking funds to take on more water issues around the state, including red tide.

“We love Mote and their scientists but something has been wrong about their take on this,” said Andy Mele with Suncoast Waterkeeper. “We need to try to move towards science-based and common sense water policy.”

Local organizations attending the event included Manatee Fish and Game Association, the Florida Institute of Saltwater Heritage, Sarasota Bay Watch, Solutions to Avoid Red Tide, ManaSota-88 and the Manatee-Sarasota Sierra Club.

After Brand’s presentation, representatives from each group spoke about issues they are addressing in the community and called for more citizens to take action on the environment.

Ryan Ballogg covers arts, entertainment, dining, breaking and local news for the Bradenton Herald. He has won awards for feature writing and environmental writing in the Florida Press Club’s Excellence in Journalism Competition. Ryan is a Florida native and graduated from University of South Florida St. Petersburg.
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