‘Suffocated to death’: Florida researchers testing water, carcasses to determine what caused fish kill

Researchers are racing to figure out what killed hundreds of fish in the Indian River Lagoon.

FOX 35 first reported on the fish kill that happened on Wednesday. Experts want to know how far it spread, and some are convinced – this is just the beginning.

Homeowners on Rocky Point Road have fewer dead fish near their docks, but the smell of rotting animals still fills the air.

 "They suffocated to death," said Mara Skadden who’s the restoration coordinator with the Marine Resources Council (MRC) and came out to test the water and carcasses.

Different species of dead animals are baking in the sun, and that decay is making the issue worse.

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"If we have large amounts of death and decay at the surface, it’s going to further zap oxygen out of this water, and it can spread," said Jessica Cline who’s also a restoration scientist with MRC.

They wanted to see how far the killing spread and are examining water, dead fish, and sediment samples from the lagoon.

What they found isn’t good: black, tar-like sand. The sand should be tan and gray colors instead.

The black tar-like substance is something animals cannot survive in.

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"Today, footage revealed it’s going to be very dark mucky. You can’t smell it on your tv, but it smells like hydrogen sulfide, rotten eggs. That is not great for our animals," Cline added.

"This is sort of a perfect storm," said Jim Moir who’s the Indian River Keeper.

He drove his boat up from Stuart and says he saw dead animals start to surface about 2.5 miles from Malabar.

"These are really serious indicators of something not right and something that may have an impact on not only our economy but our health and environment," Moir said.

He thinks numerous factors played into this specific fish kill.

"We may be seeing a high heat, low oxygen event as well as a nutrient cycle that’s inspiring an algal bloom," Moir said.

Numerous tests are on their way to labs. Researchers hope they can figure out what caused the kill before death strikes again.

"It’s just really sad to see all these things that are dead and washed up, but it also makes me want to figure out why," Skadden concluded.

If the fish kill does spread to new areas in the lagoon – you can expect to smell rotten eggs, see black tar-like sand coming to shore and more dead animals washing up from the water.

MRC is working with Florida Tech and FWC to finish testing and determine what exact toxins are in the Indian River Lagoon.