Experts worry fish kill could impact manatees

It began one week ago, as tens of thousands of fish -- more than 30 different species in all -- floated to the top along a 50-mile stretch of the Indian River Lagoon. Authorities suspect brown tide may be to blame.

"They were suffocated. They could not breath," said Dr. Robert Weaver, the director of the Indian River Lagoon Research Institute. He said he just received new data about oxygen levels in the lagoon at the the very beginning of a massive fish kill. "This would be Saturday at 2 a.m. on this line here," he said, gesturing to a chart that showed there was no oxygen at the depth of water where this sample was taken near Sykes Creek in Merritt Island.

Weaver said algae had gobbled up all the oxygen. "With all these dead fish in the water, so many people are looking at this saying, 'Who's to blame for this?'" said Weaver. "This is a tough question to answer, because we all have to look in the mirror. This problem started years ago with unfettered development over the past 50 years is what's to blame for this."

Weaver said he believes decades of fertilizer runoff by an ever growing population and antiquated storm water systems created high nutrient levels that are fueling recent algal blooms. But it's not just killing fish. He said sea grasses are likely dying too, which are the keystone of the lagoon's ecosystem.

"That's manatee food. Manatee eat sea grass. So we can expect that it's likely the manatees will start being stressed," he said. "I'm not a marine biologist, I'm not a scientist. Leave that to them to answer that question, but the scale of this fish kill, they haven't seen anything like this in 50 years."