More than 10 million fish died in Lake Cajititan because of an excess of organic matter and fecal coliform bacteria, according to a preliminary study by the Jalisco Forensic Sciences Institute.
The contamination caused an increase in algae and a drop in oxygen levels, which in turn provoked the mass deaths of the fish type known as popochaes, Marco Antonio Cuevas, IJCF’s director general, said this week
“What we are seeing in the lake today is not a natural phenomenon but a process of systematic degradation of its fragile conditions,” Cuevas said.
Lake Cajititan is located 15 miles south of Guadalajara and is sometimes referred to as Lake Chapala’s younger sibling.
The popochas are the least resistant of the fish types found in Lake Cajititlan, Cuevas said, noting that tilapia, carp and charral were not affected.
Cuevas stressed measures must be taken to reduce contamination in the lake or other fish types may also start to perish en masse.
In addition, National Water Commission (CNA) studies taken at five points around the lake show higher than normal levels of fecal matter, phosphorous, sulphur and other chemicals and particles.
On Tuesday, CNA Director Tito Lugo Arias said ten aerators would be installed in Lake Cajititlan to enhance the health of the aquatic ecosystem. The equipment will boost oxygenation and reduce the proliferation of algae, he said.
State Environment Secretary Magdalena Ruiz said Tuesday that the final total of dead fish removed from Lake Cajititlan is likely to be around 11 million. The weight of the fish could reach 275 tons. Workers and volunteers extracted the final fish floating in the lake on Tuesday. No new outbreaks of mass deaths have been reported for a week.