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Entre Ríos, Argentina – February 13, 2025: A severe bloom of cyanobacteria has spread across lakes and waterways in Entre Ríos, turning waters into a striking but toxic green. The phenomenon, exacerbated by high temperatures and nutrient pollution, poses a serious threat to local fauna, including fish and bird species dependent on these ecosystems. Environmental authorities have issued warnings, urging residents and tourists to avoid contact with the affected waters due to potential health risks. Scientists are closely monitoring the situation, assessing its long-term ecological impact. (Credit: Ignacio Rollano/UNAR AGENCY)