Potential of fish kill gives officials pause

County officials, while hoping for the best, are strategizing how they might clean up thousands of dead fish if a fish kill results from a current brown algae bloom that eerily resembles conditions that caused the massive 2016 fish kill in Brevard’s portion of the Indian River.

There have been no fish kills reported as of press time, but Brevard County Natural Resources Management Department Director Virginia Barker has created an emergency response team to map fish kills and to share river condition data, and is coordinating procedures for volunteers and contractors to remove dead fish.

“Conditions are ripening and we ought to dust off the lessons learned from 2016 and we ought to prepare,’’ she said of the bloom that appears more severe in the Banana River.

Time is of the essence when removing dead fish because the decomposition of their carcasses removes additional oxygen so that any sea life that survived the initial fish kill will die, she said.

“We have helicopter and airplane pilots willing to go up because when we get a call, we don’t know. We have to verify and check the surrounding area,’’ she said.

If the kill is small, it will be noted but nothing will be done. In case it’s large-scale like 2016, Barker is checking with other state agencies about the use of dead fish harvesting equipment. “We’re trying to figure out who has the resources, where are the resources so we can mobilize them quickly on an emergency style response,’’ she said.

Watching the weather is a big part of fish kill predictions, with the worst weather being several consecutive days of cloudy warm weather.

During daylight, algae produce oxygen through photosynthesis, replenishing oxygen levels in the water. However, at night the algae consume oxygen, causing a dip in the dissolved oxygen.

In addition, algae blooms, intensified by nutrients in the water, block the sunlight and cause damage to seagrasses. With no sun to replenish on cloudy days, the oxygen levels drop too low for fish to survive.

“You don’t want to cry wolf but it’s really darn similar. When has it ever looked like this that we didn’t have a massive fish kill? Never, because we’ve only had one,’’ she said.

Blooms can burn themselves out, but use up all the nutrients, if the weather stays cool and sunny.

Duane DeFreese, executive director of the Indian River Lagoon national Estuary Program added, “Our hope is for good conditions and no fish kill, but we can’t predict when or if it will happen. If it does happen we have a lot of tools to track what’s going on. To keep fish kills from happening in the future we need to put the lagoon on an aggressive nutrient diet,’’ he said.

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