on the Pantanal wetlands. An effort by the Rios Vivos coalition to educate people on the effects of the project was successful in delaying the project, and the nations involved agreed to reformulate their plan. The final plan is still uncertain, along with the effect it will have on the Pantanal and the ecology of the entire Río de la Plata basin. The controversy over whether or not the project will have a disastrous effect on the local ecology, as well as the potential economic gains, continues to this day. Water characteristics The Paraguay River basin includes several distinctive habitats, ranging from very clear waters such as Rio da Prata (pt) near Bonito in the upper part to the sediment-rich Bermejo River in the lower part. The suspended load of the Paraguay River is about before the inflow of Bermejo, but rises to about after. Directly after the inflow of Bermejo River, the pH of the Paraguay River may reach up to 8.2. The typical pH of the Paraguay River is 5.8—7.4 in the upper part (defined as the section before the inflow of the first non-Pantanal tributary, the Apa River) and 6.3—7.9 in the lower part. The peak of the flood season in the Paraguay River (measured at Corumbá) is delayed 4–6 months compared to the peak of the rainy season due to the slow passage of water through the Pantanal wetlands. There are significant temperature variations depending on the season. During the low-water season, the water of the Paraguay River is relatively warm (typically above ) and clouded (Secchi depth typically less than ), but in the flood season it is colder (typically ) and clearer (Secchi depth typically ). The upper part of the Paraguay River is warmer than the lower and generally its temperature does not fall below , although some upper Paraguay tributaries may fall below this. Fauna The Paraguay River ecoregion has high species richness with about 350 fish species, including more than 80 endemics. About 80% of the fish species in the river are characiforms (tetras and allies) and siluriforms (catfish). Several of these migrate up the Paraguay River to spawn, including Prochilodus lineatus and Pseudoplatystoma corruscans. Unsurprisingly many species in the river are essentially of Paraná River Basin origin, but the fauna also has a connection with two Amazonian rivers, the Guaporé and Mamoré. While flowing in different directions, the Paraguay, Guaporé