Limnology
A wide variety of commercially viable fish, 27 species of 5 families, such as Mahseer, Catla, Mirror Carp, Singhara (native) and others are recorded in the Pong Dam reservoir and its tributaries. Before the reservoir was built, catfishes, mirror carps and a few coarse fish were the dominant fish fauna in the Beas River. With the emergence of the reservoir, commercial fishing was encouraged as an important programme not only to provide employment to about 1500 fishermen but also to promote the eco-tourism potential. A planned operation of fish stocking was launched with first introduction of Common carp in 1974 and Indian major carps or Silver carp in 1976–77. This resulted in a shift in the catch structure of the reservoir, with carps accounting for 61.8% of the total landings in 1987–88. The present fish stocks in the reservoir, in the sequence of their abundance are: 1) Rohu, Aorichthys seenghala, 2) Labeo calbasu (native), 3) Tor putitora (Himalayan Mahseer), 4) Cirrhinus mrigala, 5) Wallago attu, 6) Cyprinus carpio, 7) Labeo dero, 8) Catla catla and 9) Channa sp. The reservoir, unlike other reservoirs in the region, has shown a marked growth in catch of Mahseer fish, recording 20% of the total catch during 1999-2000 with the average size of the fish ranging from 1.5–1.7 kg (3.3–3.7 lb). This is attributed to the change in the Himachal Pradesh (HP) Fishing Rules, with an added clause which specifies the minimum catchable size for Mahseer as 300–500 mm (10–20 in) or approximately 1.2 kg (2.6 lb). That rule is stated to give to each female Mahseer to breed at least once before being caught.
Mahseer angling in the Pong Dam reservoir is said to be the only one of its kind in the country.
Read more about this topic: Maharana Pratap Sagar, Flora and Fauna