TITLE: Ban on shellfish pushed southward in wake of red tide

BYLINE: Lisa Marie Gomez

CREDIT: Special to the Express-News

EST. PAGES: 2

DATE: 09/30/97

DOCID: SAEN218736

SOURCE: San Antonio Express-News; SAEN

EDITION: State; SECTION: A Section; PAGE: 01A

CATEGORY: News - Texas

(Copyright 1997)

SOUTH PADRE ISLAND - Texas's lower coast came under a ban on harvesting shellfish Monday after thousands of dead fish washed up on beaches here as a wave of red tide bloomed at the mouth of the Rio Grande over the weekend.

State health officials extended the ban, which was imposed late last week on portions of the upper coast, after finding dead mullets, menhaden, red fish, trout, snook and other fish on the southern coast Monday. And one scientist predicted conditions were ripe for this latest outbreak of red tide to get worse.

"It's calm, sunny and warm," said Dave Buzan, who heads the Texas Parks and Wildlife Department's Kills and Spills Team.

"If I were an alga, I'd be thriving," Buzan said after looking at dead fish along the gulf beaches.

Red tide is formed by microscopic algae that releases a toxin paralyzing the central nervous system of fish. It also releases an aerosol that can cause respiratory irritation in humans, and it gives the water a reddish tint.

"There were millions and millions of dead shiners (menhaden)," said David Mendez, an avid fisherman from Brownsville who first noticed the dead fish Friday.

"My friend and I were going to fish for snook out there by the mouth of the (Rio Grande), when all of a sudden you see the shiners just going around in circles and they start hitting your legs. The dead fish got heavier as you got closer to the river," Mendez recalled.

Parks and wildlife officials flew over the island Monday and saw streaks of red tide from here to 35 miles north of Port Mansfield, which is about a 60-mile stretch, said Larry McEachron, the science director of the coastal fisheries division of the agency from Rockport.

"They also saw streaks up to a quarter-mile north of the Port Isabel/South Padre Island causeway," McEachron said. "The red tide is concentrated along the coast."

Scientist Don Hockaday, who has been working with other marine biologists collecting samples of water for cell counts, said that although the toxins are lethal to fish, they don't harm humans who ingest fish infected with the red tide toxins.

"The fish don't concentrate the toxin, so there's no problem in eating the flesh of the fish because the fish doesn't store the toxin," said Hockaday, acting director of the University of Texas Pan American Coastal Studies Laboratory on South Padre Island.

"And the same thing goes for crabs and shrimp," he said.

Hockaday does caution people, however, not to eat shellfish including mussels, clams and oysters collected in the Laguna Madre and the Gulf of Mexico.

"The problem is that shellfish do concentrate the toxin, and so if somebody eats an oyster from an area that has red tide, they are likely to get quite sick," Hockaday said. "But I don't know anyone who has been killed by this virus."

Common symptoms include vomiting, diarrhea and a hot-to-cold feeling.

Tony Reisinger, a Cameron County marine extension agent, has been keeping close tabs on the red tide and said the concentration is getting worse.

"The count went up from yesterday (Sunday) off the northeast point of Port Isabel," Reisinger said.

"On Saturday, it looked like we had long red fingers reaching out for the coast because the concentrated blooms were elongated and red. It was very eerie," he continued.

Although scientists say it's too early to tell how serious this wave of red tide is, what they see now is lame compared with what they saw in 1986.

"Oh, yeah, this is nothing compared to that one," Hockaday said. "The one in '86 lasted for about two months, and it was highly concentrated."

The strong stench of dead fish seemed to keep vacationers away from the beach Monday.

"I usually take my morning walk and collect seashells," said Betty Judson, a winter Texan from Missouri. "But not today. I can't stand the smell."

Kenneth L. Conway, director of the Cameron County Park System, said the red tide hasn't deterred visitors.

"We're giving people complementary advisories about the red tide," Conway said. "This is nothing compared to 1986. We haven't had anybody check out of our parks."

Scientists said Monday there's no way to tell how long the red tide will last.

"Only time will tell," Reisinger said.

ART: Caption: Express-News Graphic Map - Red tide outbreak