There are about 60 000 reservoirs worldwide with a total volume exceeding 10 million m’ and covering 400 000 km’. Culture-based fisheries are effective means to increase productivity from these inland waters with adequate attention to carrying capacity and maintenance of environmental quality (FAO, 2014). Nevertheless, reservoir fish production has been treated as a by-product giving it less importance as a fish production system.
Kanhirapuzha reservoir located in the tropical west eastern mountainous highlands of Kerala receives a bountiful average annual rainfall of 1000-1500 mm, mainly by the southwest monsoon. This reservoir was constructed in 1980 in the Bharathapuzha river basin for the sole purpose of irrigating the down lying agricultural lands in Palakkad district and receives water from two rivers, Palakayam and lrumbagasolai. This reservoir has highly undulated basin with crusts and troughs even in the transitional zone, where the water level varied from 5.4 m to 24 m at full reservoir level. There are several land masses seen with vegetation in the middle of the reservoir.
Morphology
Kanhirapuzha reservoir with a total area of 515 ha is in the category of small reservoirs «1000ha) as per the records of the GovernrnentofIndia(Sugunan, 1995)..read more
Habitat Characteristics
Water chemistry and nutrients
The physico-chemical characteristics of the reservoir water play vital role in the productivity of the system. The important physico-chemical features ofKanhirapuzha reservoir are presented in Significant variations in these parameters were not observed between months or seasons and they largely depicted the oligotrophic nature of the reservoir.. read more
Biology of selected indigenous fishes
G. curmuca is one of the dominant native fish observed in the daily fish catch of Kanhirapuzha reservoir. It is an omnivorous, gregarious species that normally occupy deep waters in the rivers of the plains or in deep and cool pools in hilly regions and as adults migrate to smaller tributaries and streams for spawning..read more
Fisheries
Kanhirapuzha is a low productive reservoir by virtue of its oligotrophic nature. It is a culture based reservoir, which depends on artificial recruitment for the enhancement of fish production and natural productivity for growth..read more
Post-stocking yield
Stocked fishes, particularly catla and mrigal, of one year age, commenced to come in the landings from January 2010 increasing the total yield in 2010 and 2011..read more
Socio-economic status
The socio-economic status of fishermen of the Kanhirapuzha reservoir was studied for the period under report. The fishermen belong to the SC/ST Cooperative fisheries society. About 126 fishermen are members of the society. Sampling was done by collecting information from ten active fishers out of 30 fishermen operating in this reservoir. Majority of the fishermen have a middle level of educational background..read more
Salient findings
The growth performances of catla and mrigal are significant and are best suited for stocking in this reservoir. The optimum stocking density for catla was estimated at 250-350 nos.ha’ as per Lorenzen’s density dependent growth model..read more
Source-
- Central Inland Fisheries Research Institute, Barrackpore
