Lagos de Tepeyahualco y Guadalupe Victoria

Lagos de Tepeyahualco y Guadalupe Victoria is a state park in Puebla, Mexico, centered on two shallow highland lakes situated in the Llanos de San Juan Teotihuacan, a broad interior basin at approximately 2,300 meters elevation. The lakes—Laguna de Tepeyahualco and Laguna Guadalupe Victoria—occupy a semi-arid high-altitude plain that forms part of the migratory flyway for waterfowl moving along the Central Mexican Plateau. The park protects the lakes' wetland habitats, which are critical stopover and wintering grounds for thousands of migratory birds, and provides recreational access to a natural landscape increasingly surrounded by agricultural and industrial activity.

The lakes and their wetland margins support one of Puebla's most significant waterbird assemblages. During winter migration (October–March), tens of thousands of waterfowl use the lakes including northern pintail, American wigeon, green-winged teal, ruddy duck, and lesser scaup. Resident species include black-necked stilt, American avocet, white pelican (seasonal), and great blue heron. Long-billed curlews and marbled godwits stop over during migration. Several endemic amphibians including species of Ambystoma (axolotl relatives) inhabit the lake margins. The axolotl-like lake-dwelling salamanders are of particular biological interest, as highland lakes across the Mexican Plateau host regionally distinctive populations.

Vegetation around the lakes reflects the semi-arid highland character of the Llanos de San Juan Teotihuacan. Lake margins support emergent macrophytes including bulrush (Schoenoplectus spp.), cattail (Typha domingensis), and common reed (Phragmites australis). Submersed aquatic plants including Potamogeton spp. and Myriophyllum spp. provide submerged habitat for invertebrates and fish. The surrounding plain vegetation is dominated by grassland with Muhlenbergia spp. and Bouteloua spp., interspersed with xeric scrub elements including maguey (Agave spp.) and nopal (Opuntia spp.). Land use around the park is predominantly agriculture, principally maize, beans, and irrigated vegetable crops.

The Llanos de San Juan Teotihuacan is an endorheic basin—a closed drainage system with no outlet to the sea—formed by volcanic activity and tectonic subsidence during the Quaternary. The lakes occupy the lowest points of the basin floor, receiving runoff from surrounding volcanic highlands including the flanks of the Sierra Nevada (Iztaccíhuatl–Popocatépetl) massif to the west. The basin floor consists of lacustrine sediments—fine clay, silt, and volcanic ash layers—deposited over millennia. Pleistocene volcanic eruptions from the nearby Serdán-Oriental volcanic field deposited pumice and ash across the basin, recorded in stratigraphic profiles of the lake sediments.

The lakes region has a semi-arid highland climate (BSk) with cold winters and a pronounced summer rainy season. Annual precipitation averages 400–500 mm, concentrated in June–September. Winters are cold with overnight temperatures regularly below 0°C from November through February; frost damages crops and reduces emergent vegetation growth. Summer temperatures are moderate, typically 18–24°C, while winters average 8–12°C. The basin's open topography exposes the lakes to strong winds that drive water mixing and create local temperature extremes. El Niño events reduce monsoon rainfall, affecting lake levels and wetland extent, while La Niña years tend to bring above-average precipitation.

The Llanos de San Juan Teotihuacan has been occupied since at least the Early Formative period; archaeological evidence from the broader Puebla-Tlaxcala basin indicates continuous settlement for over 3,000 years. The lakes were important food resources for pre-Columbian populations, providing fish, waterfowl, and aquatic plants. Under Aztec tribute records, the Tepeyahualco area was required to supply the Triple Alliance with woven goods and agricultural products. After the Spanish conquest, the basin was divided into encomiendas and haciendas focused on sheep and cattle grazing. 20th-century land reform produced ejido smallholdings that now surround the lakes.

The state park designation for Lagos de Tepeyahualco y Guadalupe Victoria reflects recognition by Puebla state government of the lakes' importance for migratory bird conservation and as a recreational resource for the surrounding population centers. The Secretaría de Sustentabilidad Ambiental y Ordenamiento Territorial (SSAOT) administers the park. A management plan was developed to balance conservation objectives with continued agricultural use in the buffer zone and recreational fishing by local communities. Waterbird monitoring programs, coordinated with national and North American migratory bird initiatives, have tracked population trends of key species.

The primary attractions are the lakes themselves and the spectacular concentrations of migratory waterfowl from October through March. Designated bird observation areas with basic viewing platforms provide access to the lake margins without disturbing nesting and roosting areas. A walking circuit around the main lake covers approximately 5 km and passes through both wetland edge and grassland habitats. Fishing—particularly for introduced common carp and tilapia—is practiced by local residents. The open landscape offers views of the Malinche and Iztaccíhuatl volcanoes on clear days, providing dramatic scenic context for wildlife watching.

The lakes are accessible from Puebla city (approx. 100 km) or from Tehuacán via Highway 150 and state road connections. The town of Guadalupe Victoria provides the nearest services including basic food vendors and fuel. A paved road reaches the lake area; parking facilities are informal. Signage and basic facilities are maintained by SSAOT, including observation platforms and informational signs at the main access point. The peak visitation period aligns with the winter waterfowl season (November–February). No accommodation exists at the lake; visitors typically day-trip from Puebla or Tehuacán.

Lagos de Tepeyahualco y Guadalupe Victoria faces multiple threats to its ecological function. Agricultural drainage and groundwater extraction for irrigation have reduced lake water levels significantly in dry years, shrinking wetland area and concentrating pollutants. Fertilizer and pesticide runoff from surrounding maize fields has increased algal productivity and reduced water clarity. Introduced fish species—carp and tilapia—compete with native species and disturb macrophyte beds through bioturbation. Illegal hunting of waterfowl occurs during migration, despite enforcement efforts. Conservation measures include negotiating water allocation agreements that maintain minimum lake levels during dry season and establishing agro-environment agreements with adjacent ejido farmers to reduce chemical runoff.