Thousands of dead fish have appeared in recent days along the shores of Lake Chapala, with the die-off stretching over two kilometers, mostly near Ajijic, according to locals.
The cause of the mass fish deaths has sparked widespread speculation. One fisherman blamed the ongoing use of the mangueadora—a 200-meter net that has been banned for 15 years. Other residents point to pollution as the likely culprit.
Similar mass fish die-offs have been recorded over the past decade at nearby Lake Cajititlán, often referred to as Lake Chapala’s “younger sibling.” In those instances, authorities cited seasonal temperature changes and algae buildup, which reduce oxygen levels, as the primary causes. However, some independent investigators argued that contamination also played a significant role. They raised concerns that fertilizers from surrounding cornfields may have leached into the fish breeding grounds.