Diversity, Distribution and Conservation Status of Freshwater Fishes of Andaman and Nicobar Islands
Mrinal Kumar Das
*
Zoological Survey of India, Andaman and Nicobar Regional Centre, Port Blair –744102, Andaman and Nicobar Islands, India.
Chandrakasan Sivaperuman
Zoological Survey of India, Andaman and Nicobar Regional Centre, Port Blair –744102, Andaman and Nicobar Islands, India.
*Author to whom correspondence should be addressed.
Abstract
The present study investigated the species diversity, distribution patterns and conservation status of the freshwater fish fauna of the Andaman and Nicobar Islands. Sampling was conducted from October 2022 to August 2024 across six islands, and specimens were captured using cast nets and hand nets. A total of 3,552 specimens, comprising 46 fish species belonging to 13 orders, 19 families and 33 genera, were recorded. Gobiiformes showed the highest species richness (41%), followed by Cypriniformes (13%), Anabantiformes (11%) and Cyprinodontiformes (7%). Among the families, Oxudercidae had the greatest species richness, with six species. Of the 46 species, one was categorised as Endangered (Clarias magur), two as Vulnerable (Microphis insularis and Oreochromis mossambicus), and one as Near Threatened (Anguilla bicolor). Three exotic species were also recorded, of which Oreochromis mossambicus was the most abundant. The inventory documented five new distributional records from freshwater bodies of the Andaman and Nicobar Islands: Chanda ranga (Hamilton, 1822), Labeo bata (Hamilton, 1822), Poecilia reticulata Peters, 1859, Oreochromis niloticus (Peters, 1852) and Oryzias dancena (Hamilton, 1822) (Adrianichthyidae).
Keywords: Freshwater ichthyofauna, island biodiversity, species richness, fish distribution, conservation status, endemic fishes, introduced fishes, Andaman Islands, Nicobar Islands, freshwater habitats