Wildlife, Sea Grass Die-offs in Northern Indian River Lagoon Perplex Researchers
October 3, 2013 | WMFE - The Indian River Lagoon is in crisis. The lagoon stretches more than 150 miles from the Space Coast to Fort Pierce. It's among the most biologically diverse estuaries in North America. Water releases from Lake Okeechobee have devastated the southern lagoon. But in the northern lagoon the problems are a mystery.
The problems began in 2011 with an algal superbloom that killed 47,000 acres of sea grasses. The following year a brown tide swept the northern lagoon.
This year nearly 70 dolphins have died, along with more than 100 manatees and hundreds of pelicans.
It's a Friday, and the Banana River is bustling with recreational boaters, jet skiers and wind surfers.
"As you can see behind the boat here the discolored water a little bit, that's a result of a microalgae bloom."
Troy Rice is director of the Indian River Lagoon National Estuary Program.
The Banana River lost nearly all of its sea grasses in the 2011 superbloom.
I can see Kennedy Space Center and a school of dolphins not far from our boat. The dolphins are a good sign, but Rice says the sage green water and foamy wake are bad.
"It should look certainly a lot clearer than it is. The water clarity should be much improved. While you may not always be able to see the bottom of the lagoon at least you should have better light penetration, and the water color would be not quite as brown as it is today. Perhaps it would be blue-green."
Researchers believe a cold snap triggered the 2011 superbloom, shielding sea grasses from sunlight. They think the sea grass die-off might have disrupted the food chain, starving dolphins and pelicans and forcing manatees to eat toxic seaweed.
Megan Stolen of the Hubb-SeaWorld Research Institute says the dead dolphins are turning up emaciated. Biologists call them peanut heads.
"Because they're losing all of the body fat in that area. They store fat around their neck. And when all of that fat goes away they get a peanut-shaped head, and you can actually see the bones in their head."
It's not just biologists who are worried.
The Indian River Lagoon has an economic impact estimated at $3.7 billion annually. It draws fishermen and wildlife watchers and sustains property values and businesses.
Fish hang on the walls of the Nautical Spirits Bar and Grill at Merritt Island's Harbortown Marina. John Weber sits at the bar. He's boated and fished on the lagoon for 20 years.
"This time of year you could walk on top of the schools of mullet out there. Now they're hard to catch. You used to always catch mullet and use them for bait to go after the reds and the sea trout, and they're just not around anymore, and its year after year."
Nearly a dozen academic organizations and government agencies are researching the Indian River Lagoon's problems. The Florida Senate has appointed a committee on the lagoon, and the state's congressional leaders are meeting in Washington about the problems.
Researchers are experimenting with transplanting sea grasses to hard-hit areas. There's also discussion of creating inlets to let more fresh seawater flow into the lagoon.
But Troy Rice says the Indian River Lagoon's problems are more complex. He says the lagoon doesn't flow like a river, and so freshwater drainage and runoff carrying fertilizers and other waste remain there for a long time. He says the lagoon might be at a tipping point.
"If we continue to dump our stormwater and freshwater into the lagoon and not have a better handle on the nutrients coming from the other sources like the groundwater and things like that, we could see the lagoon unfortunately become a different system."
He says Mother Nature is resilient, but restoring the lagoon back to full health could take decades.