Fish mortality reported in Ucero River and San Lorenzo stream

Reports of significant fish mortality have emerged in two separate regions. In Spain, the Sociedad de Pescadores de los ríos Abión y Ucero has reported hundreds of dead fish, including trout, gobies, and crabs, along a two-kilometer stretch of the Ucero River. Local fishermen noted a foul odor and a layer of dark sludge on the riverbed near a wastewater treatment plant. The Duero Hydrographic Confederation (CHD) and environmental agents have launched an investigation to determine if a discharge from the facility is responsible.

In Argentina, specialists from the Directorate of Natural Resources in Corrientes investigated fish deaths in the San Lorenzo stream. Unlike the situation in Spain, technical reports indicate that physicochemical parameters, including dissolved oxygen and pH levels, remain within normal ranges. Experts attribute the mortality in San Lorenzo to environmental factors, specifically low water levels and sudden temperature drops during winter, which likely caused thermal stress in the fish populations.