Habitat utilization and preference of cyprinid fishes in the Western Ghats streams of South India

Abstract

Freshwater ecosystems in the tropical regions are facing significant threats due to anthropogenic disturbances and habitat alterations. Tropical freshwater habitats comprise a fraction of the Earth's water and surface and are crucial for biodiversity as they house 40% of global fish diversity. This study focused on the biodiversity and habitat utilization of dominant cyprinid fish species across 21 streams in the Western Ghats. Field assessments indicated varying habitat characteristics and preferences among cyprinid species, with shallow pools and slow riffles being important for fish reproduction and survival. Over 2,700 fishes were collected, and species such as Hypselobarbus and Puntius favoured specific habitat types based on size and ecological needs. The analysis of habitat features showed strong associations with fish density, thus highlighting the diverse stream conditions for fish populations. Conservation measures are critical for threatened cyprinid species, as overfishing poses a threat to their survival. The necessity for immediate action by competent authorities and conservationists is emphasized to protect the vital ecosystems having the diverse fish species which ensures freshwater biodiversity sustenance in the Western Ghats.