Red tide has increased in the past 15 years, but some of the increase could be due to increased reporting, U.S. experts say.

Red tide occurs when the single-celled microscopic algae, which kills fish and turns water red, thrive and multiply. This usually happens in the spring and summer in response to increased light intensity and favorable levels of salinity and nutrients in ocean water. During such "blooms," each single algae cell may replicate itself 1 million times.

"We don't have any good way of predicting it from year to year," said Tracy Villareal, of the University of Texas Marine Science Institute, who spoke at the State of the Gulf of Mexico Summit Thursday in Corpus Christi, Texas. "My suspicion is we're not going to see fewer of them."

Some of the increase may be due to better reporting, but probably not all of it, according Villareal.

The science is moving in the direction of understanding red tide, but it's slow going, Villareal told the Corpus Christi (Texas) Caller-Times.

Copyright 2006 by United Press International