Diversity and longitudinal distribution of fishes in the Soto La Marina River basin, Mexico, and relationship with environmental variables

• Published in: Environmental biology of fishes 2021-10, Vol.104 (10), p.1321-1339
• Main Authors: Ruiz-Campos, Gorgonio, Martínez-Vázquez, Ana Verónica, Contreras-Catala, Fernando, Hernández-Guzmán, Rafael, García-De León, Francisco Javier
• Format: Article
• Language: English
• Subjects: Animal Systematics/Taxonomy/Biogeography; Anthropogenic factors; Biomedical and Life Sciences; Conductivity; Dissolved solids; Distribution; Dominant species; Environment; Fauna; Fish; Fish conservation; Fishery resources; Freshwater & Marine Ecology; Geographical distribution; Heterogeneity; Life Sciences; Mountains; Nature Conservation; Principal components analysis; River basins; River mouth; Rivers; Salinity; Salinity effects; Salinity gradients; Species diversity; Species richness; Temperature gradients; Total dissolved solids; Zonation; Zoology
• ISSN: 0378-1909; 1573-5133
• DOI: 10.1007/s10641-021-01158-9

The spatial and temporal heterogeneity of rivers largely determine both the richness and the variability of the fish assemblages; however, few studies have been carried out in the northern parts of Mexico. This study assesses the species diversity and longitudinal distribution of fish fauna in the Soto La Marina River (northeast Mexico) and how this relates to environmental variables in an area of biogeographic transition of the Nearctic and Neotropical regions. A total of 89 species (82 natives and seven exotic) belonging to 67 genera and 39 families were recorded. The fish fauna in this basin shows a clear biotic zonation represented by three different species assemblages related to the three physiographic zones of the river (mouth, plain, and mountain) with a replacement of species throughout a temperature and salinity gradient. A principal component analysis found that Astyanax mexicanus , Poecilia mexicana , and Herichthys cyanoguttatus were the most abundant species in the plain and mountain zones of the river but exhibited different high abundance hotspots throughout the basin. Salinity, conductivity, and total dissolved solids increased downstream, directly impacting fish composition and diversity. The mouth of the river was characterised by high salinity and conductivity values correlating with high species richness of marine derivation. Similarly, the richness of species negatively correlated with the longitudinal gradient of the river. An integral knowledge of the relationship between environmental and anthropogenic parameters in the Soto La Marina River basin will enable the design of conservation and management strategies for its fish resources and habitats.