Thousands of fish turned up dead in a lake in a Baja California border city last week and authorities said it could be due to a natural phenomenon provoked by scorching temperatures.
Biblical in appearance, a white sheet of fish carcasses covered the surface of the México lagoon in Mexicali, as seen in a video posted to social media on Friday.
In the video, a blanket of motionless fish are seen across the lake, stretching for hundreds of meters. The fish species have been confirmed as Mayan sardine, gizzard shad, black bass, European common carp and African tilapia.
Temperatures of 45 C (113 F) are thought to have lowered water levels, provoking a reduction in the lake’s oxygenation, leaving the fish vulnerable, the news site Excelsior reported. However, the head of a process control laboratory for the State Comission of Public Services in Mexicali (CESPM), Abraham Castro, said that rain was the causative factor, which he said had disturbed sediments at the bottom of the lake.
Mexicali Mayor Norma Bustamante denied that the deaths had been caused by waste dumping in the lake.
Mexicali’s head of wastewater for the CESPM, Benjamin Carrillo, said the phenomenon occurs twice a year, in August and again in March or April and that it can be sparked by cloudy conditions, causing the lake’s oxygen levels to dive.
National Water Commission (Conagua) personnel collected the bodies of the fish for further analysis.