Rio Tamasopo, San Luis Potosi, Mexico

Environment

Environment

Affected by human activity

Affected by human activity

Agriculture

Agriculture

Advanced

Surrounding area

The surrounding area of Rio Tamasopo is characterized by lush and diverse natural landscapes. It is typically covered with tropical vegetation, including dense evergreen forests, abundant plant life, and vibrant vegetation. The region is known for its rich biodiversity, with a wide variety of plant and animal species.

The climate in the area is generally warm throughout the year, with temperatures ranging from approximately 25 to 30 degrees Celsius. This favorable climate supports the growth of a thriving ecosystem and contributes to the beauty of the surroundings.

The terrain near Rio Tamasopo often features hills, valleys, and rugged landscapes. The river itself carves its way through the terrain, creating cascades, waterfalls, and natural pools that are popular attractions for locals doing the dry season.

During the rainy season the river is undergoing significantly changes. As the water level rises the riverbeds become flooded, carrying a considerable amount of sediment that clouds the water, rendering it impossible to see anything beneath the surface. In this period water parameters changes as well, making big seasonable changes for the fish as well.

Underwater landscape

The underwater realm of Rio Tamasopo reveals a fascinating array of fish species. Among the diverse inhabitants, we can encounter:

• Xiphophorus montezumae (Poeciliidae)
• Poecilia mexicana (Poeciliidae)
• Herichthys tamasopoensis (Cichlidae)
• Astyanax mexicanus (Characidae)

Xiphophorus montezumae, aptly named after the Aztec emperor Moctezuma I, boasts an impressive feature known as the Montezuma swordtail. This unique extension exhibits remarkable proportions, often growing up to two-thirds the length of the fish’s body. It is not uncommon to witness specimens measuring around 5-6cm in length, with awe-inspiring swords stretching 7-9cm.
The primary pool experiences near stagnant currents, enriched with oxygen due to the mesmerizing flow of the Tamasopo waterfall cascading into it.

Vegetation within the rivers and primary pool is moderate, mainly comprising algae, brushes, and shrubs along with some submerged grassy types of vegetation, that gets covered doing the raise and fall of the rivers waterlevel.

The rest of the biotope is adorned with rocks, logs, and fallen leaves from the surrounding trees. The bottom substrate also varies, with the main pool consisting mainly of coarse gravel, while the rivers feature finer sand to medium-sized gravel. In some areas, there are sections with a mountainous bottom, particularly before the waterfalls.

Overall, Rio Tamasopo offers an exceptional opportunity to observe fish in their natural habitat, showcasing the diverse underwater landscape of the region.

Fishlist:

• Xiphophorus montezumae (Poeciliidae)
• Poecilia mexicana (Poeciliidae)
• Herichthys tamasopoensis (Cichlidae)
• Astyanax mexicanus (Characidae)
• Poeciliopsis gracilis (Poeciliidae)
• Tampichthys catostomops (Cyprinidae)
• Herichthys pame (Cichlidae)
• Herichthys steindachneri (Cichlidae)

Aquatic plants:

• Ceratophyllum demersum (Ceratophyllaceae)
• Bacopa monnieri (Plantaginaceae)
• Marsilea mollis (Marsileaceae)
• Ludwigia peploides (Onagraceae)

Wetland plants:

• Setaria geniculata (Poaceae)
• Arundo donax (Poaceae)

Threats to ecology

The delicate ecology of Rio Tamasopo faces numerous threats, primarily stemming from human activities such as tourism and deforestation. The influx of tourists, while bringing economic benefits, can exert significant pressure on the ecosystem. The area around the main pool is extremely popular with both locals and tourists who use it to bathe and relax. There is also a camp site located close to the area, which also contributes to pressure on the ecosystem.

Deforestation, driven by various factors including agriculture, logging, and urbanization, poses a severe challenge to the ecological stability of Rio Tamasopo. The clearing of forests along the riverbanks not only diminishes the natural beauty of the area but also results in the loss of critical habitats for numerous plant and animal species. From 2002 to 2021, Tamasopo lost 1.73kha of humid primary forest, making up 25% of its total tree cover loss in the same time period.

Riparian zone

Trees near the aquatic habitat

Many -

Bibliography

• First Edition 2009 Third print. - Freshwater fish biotopes in Mexico by Kai Qvist and Rune Evjeberg
  ISBN 978-87-993012-0-1
  
• → Poecilia bladet - Artsbeskrivelse: Xiphophorus montezuma by Rune Evjeberg
  ISBN ISSN 0349-7380
  
• → American Currents - Vol. 45, No. 1 - ANOTHER SLICE OF MEXICO by Konrad Schmidt
  
• → 1999 - Diversidad de plantas acuáticas y subacuáticas en ríos y arroyos de la Cuenca del Pánuco by Córdova Delgado, Brenda Carlina
  ISBN 1645 - RI003595
  

Sitography

Comment by the expert