Biologists along the South Texas coast are testing for red tide after reports of discolored water and extensive fish kills resulting from the toxic algae.
Officials say reports of the algae came throughout the week in the areas of Corpus Christi, Port Aransas, Matagorda Island and Padre Island.
The toxic algae gives a reddish hue to the water. The blooms also choke off oxygen in the water, destroying undersea life. The organisms emit a toxin that paralyzes fish and causes discomfort for humans breathing the mist.
Officials say visitors Sunday at Padre Island National Seashore spotted red water and reported respiratory irritants.
But Meridith Byrd of the Texas Parks and Wildlife Department says much of the area remained safe for recreational activities.
She tells the Corpus Christi Caller-Times that people can always move a bit north or south to find areas of clear water.