India is home to a diverse range of freshwater fish species, with over 2,500 known species found in its rivers, lakes, and ponds. These fish species vary in size, color, and habitat, and are of great ecological and economic importance. Many of these species are popular food fishes, while others are highly sought-after by anglers and aquarium enthusiasts. The most commonly found freshwater fishes in India include rohu, catla, hilsa, snakehead, mahseer, Indian carp, and gourami. However, there are many more species that are endemic to specific regions or habitats, making India a unique and rich destination for freshwater fish enthusiasts. Despite their significance, many of these species are under threat due to habitat destruction, pollution, and overfishing, highlighting the need for conservation efforts to protect these valuable aquatic resources.
The Walking Catfish, also known as Clarias batrachus, is a freshwater fish species found in Southeast Asia, including India, Bangladesh, and Thailand. It is a hardy species that can survive in a range of aquatic environments, including low-oxygen and stagnant water. The fish has the unique ability to breathe air, which allows it to survive for extended periods out of the water, hence its common name. Walking Catfish has a cylindrical body, with a mottled brown coloration and long, whisker-like barbels around its mouth. It can grow up to 50 cm in length and weigh up to 3 kg. Walking Catfish is an important food fish in some regions, but it is also considered a pest in others due to its invasive behavior. The fish can move overland, using its fins to “walk” across the ground, allowing it to colonize new water bodies and disrupt local ecosystems. As a result, the species has been listed as one of the world’s 100 worst invasive alien species. Efforts are underway to control the spread of the Walking Catfish, including the use of barriers and the promotion of sustainable fishing practices.
| Serial Number | Characteristics | Description |
| 1 | Common name | Walking Catfish |
| 2 | Scientific name | Clarias batrachus |
| 3 | Colour | Dark brown or gray with mottled patterns |
| 4 | Average length in m | 0.3 – 0.4 meters |
| 5 | Average weight in kgs | 1 – 3 kilograms |
| 6 | Found in river systems of | Ganges, Brahmaputra,Godavari , Krishna |
| 7 | Habitat | Freshwater habitats, such as rivers, streams, ponds, and swamps |
| 8 | Any special characteristics | Can “walk” on land using its pectoral fins, and can breathe air through its skin or a modified swim bladder called a labyrinth organ. |
Features
The Walking Catfish, also known as Clarias batrachus, is a freshwater fish that is native to Southeast Asia but has been introduced to other parts of the world, including Africa, South America, and North America.
Walking Catfish are generally a dark brown or gray color with a mottled pattern, although the color can vary depending on the fish’s habitat.It can grow up to 24 inches (60 cm) in length and weigh up to 6.6 pounds (3 kg), although they are more commonly around 12-15 inches (30-38 cm) in length and weigh around 2-3 pounds (0.9-1.4 kg).
Walking Catfish are not known for their speed in the water, as their name suggests, they are more adept at walking along the bottom of streams, ponds, and other bodies of water using their strong pectoral fins to “walk” on the substrate. Walking Catfish have a long dorsal fin that runs along the length of their back, and a pair of long, barbels or whiskers that protrude from their upper lip. They also have a spiny first ray on their pectoral fins and three spiny rays on their anal fin, which they use for defense against predators. Additionally, Walking Catfish are able to breathe air through a specialized organ called a labyrinth organ, which allows them to survive in low-oxygen environments or even out of water for short periods of time.
Habitat
Walking Catfish prefer shallow, slow-moving or standing water bodies such as swamps, ponds, marshes, and rice paddies. They are also known to inhabit slow-moving streams and rivers with muddy or sandy bottoms. They can tolerate a wide range of environmental conditions, including low oxygen levels, high water temperatures, and low water quality, which makes them well-adapted to survive in different habitats.
Additionally, as their name suggests, Walking Catfish are able to move across land and can travel short distances over moist ground to reach other water sources during the dry season or to escape predators. This ability to move over land makes them particularly difficult to control in areas where they have been introduced and have become invasive.
River System
The Ganges River system is the largest river system in India and the walking catfish is found in the main river as well as its tributaries like the Yamuna, Ghaghara, Gandak, and Kosi.
The Brahmaputra River system in Northeast India is another major river system where walking catfish can be found. It includes the Brahmaputra River and its tributaries like the Subansiri, Kameng, and Manas.
The Godavari River system in South India is home to the walking catfish. It includes the Godavari River and its tributaries like the Penganga, Wardha, and Pranhita.
The Krishna River system in South India is another major river system where walking catfish can be found. It includes the Krishna River and its tributaries like the Tungabhadra and Bhima.
The Cauvery River system in South India is also home to the walking catfish. It includes the Cauvery River and its tributaries like the Kabini and Hemavati.
It is important to note that walking catfish are not native to all of these river systems and have been introduced in some areas.
Threatened Status
The Walking Catfish (Clarias batrachus) is not currently listed as a threatened or endangered species by the International Union for Conservation of Nature (IUCN). However, it is considered an invasive species in many parts of the world where it has been introduced outside of its native range, including in Southeast Asia, Africa, and North America.
As an invasive species, the Walking Catfish can cause ecological harm by competing with native fish species for resources, preying on native fish and their eggs, and altering habitats. In some areas, they have been known to cause declines in local fish populations and disrupt aquatic ecosystems.
Additionally, the practice of introducing the Walking Catfish for mosquito control in rice fields and other water bodies has resulted in the accidental introduction of the species to many new areas, where it has become established and caused problems. Therefore, efforts are needed to control its spread and prevent further introductions of this species to new habitats.
