TEXAS— Over the weekend of June 9, Texas beachgoers stumbled upon thousands of dead fish that had washed ashore on the Gulf of Texas, coating the shoreline in a blanket of fish carcasses. According to local officials, the Friday waves from the Gulf of Mexico pushed the dead fish onto the shore in Brazoria County, 41 miles south of Houston.
According to Texas Parks and Wildlife Department officials, low dissolved oxygen levels in the water made it hard for the fish to breathe. The rare occurrence is called “fish kill” and is becoming more common as temperatures rise during the summer. The event hasn’t been linked to climate change. Still, researchers have stated that events like these can be expected to increase as temperatures increase and oxygen levels in water drop across the United States and Europe.
According to the United States Geological Survey, dissolved oxygen is the measure of how much oxygen is dissolved in the water— the amount of oxygen available to living aquatic organisms and the amount of dissolved oxygen in a stream or lake can tell a lot about the water quality. Dissolved oxygen levels will increase with photosynthesis, the process by which green plants use sunlight to synthesize food from carbon dioxide and water. When less sunlight is present, the photosynthesis process is slowed, and it stops at night, all while aquatic plants and animals continue to consume oxygen at the same rate, which causes to decrease in concentrated oxygen.
The most affected species to wash up were Gulf menhaden, the most used bait species for fishermen. The potential silver lining is that Gulf menhaden washing ashore will be a popular snack for sea animals, and a significant nutrient surplus will be fed into the environment.