Researchers are on the lookout for red tide at South Padre Island.

The first sign of the algae that gets into the air and makes your throat burn was detected at Isla Blanca Park, but it quickly disappeared.

A sample taken Monday of the water at Isla Blanca Park found a red tide level of 800 cells per milliliter. A Thursday check came up with no signs of red tide.

Tony Reisinger, an extension agent with Sea Grant with Texas A&M University, said the samples taken from the South Padre Island Gulf and the Laguna Madres didn’t show similar levels of red tide.

“We found it on the 18th, the 19th and then yesterday we only found three cells per milliliter,” Reisinger said Thursday. “And now today, zero.”

“I'm optimistic that it's not going to hang around,” Reisinger added.

But after the alert sent earlier this week, researchers said they'll continue monitoring samples.

“The only thing predicable about red tide is its unpredictability,” Reisinger said.

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