GLENHAVEN >> The hot weather and algae blooms are being blamed for the fish die-off that occurred Monday off the Indian Beach Resort in Glenhaven.

Ken Taddie, manager of the Indian Beach Resort, said he observed hundreds of dead threadfin shad around the resort’s docks early Monday morning. Later in the day he observed dead and dying adult bass, catfish, crappie and bluegill. According to Taddie, many fish were swimming on the surface gasping for air. He said there was no wind and the water around the resort is undergoing a heavy algae bloom.

Taddie said he asked the resort’s clients to start up their outboard motors on their boats to help aerate the water. Within 30 minutes the fish were swimming normally and the die-off appeared to be over. The wind also increased, which helped stir up the water

Experts believe the die-off is because of a lack of oxygen. Fish die-offs are a common occurrence on Clear Lake during the hot summer months. The water around the resort is protected from the winds and the recent 100-plus-degree days have resulted in a depletion of dissolved oxygen.

Dissolved oxygen consists of oxygen molecules that enter the water through wave action and other water movement. A fish will inhale water through its mouth and as the water passes over the gills the oxygen molecules are extracted from the water and passed to the blood of the fish, similar to what occurs in the lungs of mammals. When there are algae blooms the dissolved oxygen is often depleted.

Dissolved oxygen levels are measured on a scale of 0-20. Bass and crappie require a dissolved oxygen level of at least 3 although 5 or above is considered optimum. When the level falls below 3 the fish that remain in the area will die.