Men fishing in the traditional manner in Lake Atitlan, Guatemala, 2022 (photography)

Men fishing in the traditional manner in Lake Atitlan the largest lake of Guatemala. Polluted lakes. The waters of Lake Atitlán turn green due to the appearance of a toxic algae called cyanobacteria. Lake Atitlán is of vital importance for the 15 municipalities that are part of this basin. It generates jobs, is a source of water for some 80,000 people and is also a first-class tourist destination. It is estimated that the population around the basin is about 400,000 inhabitants. Increased discharge of sewage, sediment, and nutrients contribute to algal growth and cause blooms in the lake. These can originate in different species of aquatic plants, of which cyanobacteria turn out to be the most toxic. These algae produce a degradation that limits the excess of sun and oxygen to other organisms in the lake. Cyanobacterial overpopulations are also the ecosystem's response to increasingly common tropical storms due to climate change.