Freshwater Fish

  

Sri Lanka, a tropical island in the Indian Ocean, is home to a diverse array of freshwater fish species, many of which are endemic to its rivers, lakes, and wetlands. The island’s freshwater ecosystems are influenced by its monsoon climate, with rivers flowing from the central highlands to the lowlands, creating a variety of aquatic habitats.

Diversity of Freshwater Fish in Sri Lanka

Sri Lanka boasts more than 90 species of freshwater fish, with over 50 species being endemic. The country’s freshwater fish can be classified into different groups based on their habitat, behavior, and ecological role.

1. Endemic Freshwater Fish

Several fish species are found only in Sri Lanka, making conservation efforts crucial. Some notable endemic species include:

• Sri Lanka Zebra Loach (Lepidocephalichthys jonklaasi) – A small, beautifully patterned fish found in slow-moving waters.
• Blotched Filamented Barb (Dawkinsia singhala) – A strikingly colorful species commonly found in streams and rivers.
• Sri Lanka Green Barb (Pethia nigrofasciata) – Known for its black horizontal stripes, this species is popular in the aquarium trade.
• Spotted Gourami (Trichogaster pectoralis) – A native labyrinth fish adapted to low-oxygen environments.

2. Commercial and Invasive Species

While many native species thrive in Sri Lanka’s waters, some introduced fish species have also established populations. Some of these include:

• Tilapia (Oreochromis mossambicus) – Originally introduced for aquaculture, tilapia now competes with native fish.
• Asian Arowana (Scleropages formosus) – Occasionally found in ornamental fish markets.
• Snakehead Fish (Channa striata) – A predatory species commonly found in marshes and rivers.

3. River and Wetland Species

Sri Lanka’s extensive river systems and wetlands support various freshwater species, such as:

• Freshwater Eel (Anguilla bicolor) – A migratory species that moves between freshwater and marine environments.
• Puntius species (Barbs) – These small, colorful fish are an essential part of the ecosystem and are widely found in Sri Lanka’s rivers.

Conservation and Threats

Many freshwater fish in Sri Lanka face threats due to habitat destruction, pollution, and overfishing. The introduction of invasive species has also impacted native populations. Conservation efforts focus on protecting natural habitats, preventing over-extraction of water resources, and promoting sustainable fisheries.

Conclusion

Sri Lanka’s freshwater fish are an essential part of its biodiversity, with many species being