Tens of thousands of dead fish wash up on a Texas beach due to low oxygen levels

QUINTANA, Texas (AP) — Tens of thousands of dead fish washed up on the Texas Gulf Coast over the weekend, covering the shoreline with rotting carcasses and leading local officials to warn visitors to keep away.

Waves from the Gulf of Mexico pushed in dead fish “by the thousands” Friday in Brazoria County, which is over 40 miles (64 kilometers) south of Houston, Quintana Beach County Park officials said.

Low levels of dissolved oxygen in the water made it difficult for the fish to breathe, Texas Parks and Wildlife Department officials said. The phenomenon — known as a “fish kill” — is common as temperatures rise in the summer, the state department said.

While no one has connected this specific incident to climate change, researchers have said such kills may become more prevalent as temperatures warm and oxygen levels in lakes across the United States and Europe drop.

Dissolved oxygen levels increase with photosynthesis, the process by which plants transform sunlight, water and carbon dioxide into oxygen. When there is less sunlight, photosynthesis slows and at night it stops. But plants and animals in the water continue to consume oxygen at the same rate, decreasing the concentration, Texas Park and Wildlife officials said.

Gulf menhaden, which fishermen commonly use for bait, was the species most affected in the kill, Texas Parks and Wildlife said.

By Sunday evening, Quintana Beach was mostly cleared of the dead fish save for some that machinery couldn’t remove, county officials said.