9 Investigates manatee deaths in Indian River Lagoon

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BREVARD COUNTY, Fla. - The number of manatee deaths along the Indian River Lagoon continues to grow.

Officials are attributing the deaths to an "unusual mortality.” But experts hope it isn't a trend.

Channel 9’s Melonie Holt asks if we're likely to see more manatee deaths and what can be done to protect them.

Watch this story Friday on Eyewitness News at 5:30 p.m.

The number of manatee deaths along the Indian River Lagoon being attributed to an "unusual mortality,” is still growing, Eyewitness News has learned.

Channel 9's Melonie Holt found out there's concern with so little seagrass that Brevard County could see more deaths.

“So many people come to Florida and that's their dream to be able to see a manatee,” said Capt. Tonya Morgan, with Wildside Tours.

Some of the marine mammals are dying in what Florida Fish and Wildlife has called an "unusual mortality event." More than 160 manatees have died and officials believe it’s tied to a loss of seagrass linked to an accumulations of algae that started more than four years ago.

About a dozen deaths in 2016 have been linked to the "unusual mortality event,” officials said.

“We won't see long term recovery until we address those human impacts that are driving the blooms. And that's nutrient pollution septic tanks, faulty sewer systems, muck that's already in the lagoon needs to be removed,” said Dr. Duane Defreese, with the Indian River Lagoon Council.

Scientists said they think the manatee deaths may have been brought about by dietary changes brought on by localized changes in the environment, but they said they are still investigating.

“So in 2011, we went from what looked like an improving system with relatively good health, had a massive algae bloom that has been cycling on and off since 2011. The immediate impact of that bloom and subsequent blooms, is we've lost 60 percent of seagrass that is the primary food of manatees,” Defreese said.

The seagrass serves as a nursery for juvenile fish and a habitat for other animals.

“We have more species in this whole entire lagoon system then anywhere in the United States, and we need to save this,” Morgan said.

Brevard County voters just approved a half cent sales tax to pay for a 10-year, $300 million plan to clean up the Indian River Lagoon.

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