Lago de Cuitzeo

Lago de Cuitzeo spreads across a valley of the Trans-Mexican Volcanic Belt north of Morelia, mostly in Michoacán with a small part in Guanajuato. It takes its name from the town of Cuitzeo del Porvenir on its north shore. It is Mexico's second-largest freshwater lake after Chapala, covering somewhere between 300 and 400 square kilometres, but it is never more than about 10 m deep and its size changes constantly with the rains: scientists call it astatic. It lies in a closed basin of some 4,000 square kilometres that does not drain to the sea; its main feeders are the Grande de Morelia, the Viejo de Morelia and the Queréndaro rivers, which enter through the marshy centre of the lake, and a canal cut to the north lets high water drain toward Lake Yuriria and the Lerma river.

The lake is irregular, with northern, western and eastern arms joined by that central marsh, and two highways run straight across its western part on causeways: the free Federal Highway 43 and the 43D toll road between Morelia and the Bajío, while the 15D motorway skirts the south shore. The western section is saltier and supports unusual fisheries of clam shrimp, and the basin is the only home of a subspecies of the Mexican garter snake. Local people fish for charal, carp, mojarra and tilapia, catch frogs and weave the lake's tule reeds into mats, baskets and animal figures in San Agustín del Pulque, sold on weekends in Cuitzeo's main square.

In winter many migratory birds stop on the lake, and flocks of hundreds of pelicans and white egrets can be seen; Cuitzeo is part of the Western Hemisphere Shorebird Reserve Network as a site of regional importance. The lake is under heavy pressure: water extraction for farming, pollution, deforestation and evaporation from its broad, shallow bed have shrunk it, and in early 2024 Mexico News Daily reported that it had lost about 70 percent of its water over 25 years, after three dry years in a row, hurting the fishermen who depend on it. Around the shore are hot-spring pools, the most numerous at Huandacareo, and the small Tres Cerritos archaeological site near Cuitzeo.