in surrounding areas leads to high levels of nitrates, ammonium and phosphates from fertilizers being washed into the lagoon, causing eutrophication, an excessive growth of algae and bacteria that deprives the water of oxygen. A similar event occurred in August 2021, with four to five tons of dead fish being removed from the lagoon within a week. Shortly thereafter, a large demonstration took place, with 70,000 people surrounding the entire lagoon on August 28, 2021. Panoramic view of Mar Menor and La Manga Notes External links Mar Menor Tourism Site Unofficial La Manga del Mar Menor Tourism guide Mar Menor Activities Landforms of the Region of Murcia Lagoons of Europe Coastal lagoons Bodies of water of Spain Wetlands of Spain Ramsar sites in Spain Special Protection Areas of Spain World Heritage Sites in Spain Biosphere reserves of Spain Birdwatching sites in Spain Eutrophication Ecocide Protected areas of the Region of Murcia