Finfish Breeding and Hatchery Management

Unit 1 - Fish seed resources and natural breeding of finfishes

1.1.7. Coldwater fish seed resources

• The optimum range of temperature for cold water fish is 10-12⁰C.
• In India, lakes and streams located at more than 900 m above mean sea level qualify for coldwater. Trouts, salmon and mahseers are the typical cold water fishes in India.

Trout, salmon and char

• Trout and salmon are the only exotic game fishes introduced in India.
  The species of trout introduced are rainbow trout, brown trout, eastern brook trout, golden rainbow and tiger trout (a hybrid between Salmo trutta fario x Salvelinus fontinalis).
• In the Peninsular India trout has been introduced in the Nilgiris and Kodai hills in Tamil Nadu and in the high ranges of erstwhile Travancore in Kerala.
• In the Himalayas, trout has been introduced in Kashmir and Himachal Pradesh, in Garhwal Himalayas, Arunachal Pradesh, Nagaland, Meghalaya and in certain waters of Nepal.

Mahseers

• The mahseers are regarded as a sacred fish by the Hindus.
• They are distributed in streams, rivers and lakes in the hilly regions of the Himalayas and the Peninsular India. They are found in the plains where water is cool, clear with high oxygen content.
• There are seven species of mahseer belonging to the genus Tor in India. They are: Tor tor, T. putitora, T. khudree, T. nelli, T. progenius, T. mussullah and T. mosal. Mahseer fishery resources are protected in temple pools by Temple authorities

Snow trout

• Snow trout (Schizothorax spp.) are believed to have migrated into the lakes and streams of Kashmir from Central Asiatic watersheds.
• Most of them are now regarded as endemic to the Kashmir valley.
• Presently, there are eleven valid species of Schizothorax. Schizothoracids collected from different lakes and streams have been successfully induced bred.

Hilsa, Tenualosa ilisha

• The anadromous Indian shad, Tenualosa ilisha (Hamilton), commonly known as hilsa or river shad is, undoubtedly, one of the most commercially important fish of the country.
• Hilsa ascends the freshwater stretch of all the major river systems from sea mainly for breeding, thereby forming a lucrative fisheries in freshwater and brackishwater.
• It’s upstream migration has greatly been hampered by the construction of dams, weirs and barrages across the rivers.