El agua, nuevo campo de batalla y vulneración de derechos humanos

Table 21. Tilapia Farming Regions in the Country based on Farming Intensity Intensive Farming, 15

ton or above/ha

Semi-intensive Farming, 10-14 ton/ha

High-Density Farming, roughly 8-9 ton/ha

Bogra Joypurhat Pabna

Norshindi Brahmanbaria Feni

Jhenaidah Jessore Noakhali

Kishoregongj Dinajpur Chaudanga

Naogaon Satkhira Gaibandha

Kustia Jessore Hobigonj

Netrokona Mymensingh Shariatpur

Jamalpur Sherpur Madaripur

Tangail

7.6.1 Monoculture of Pangas

Pangas is relatively a larger fish compared to tilapia. The fish has better market with size ranges of 500-1000g and above. However, fish as small as 300g are often sold in markets.

Conventional grow-out of pangas with or without in-house nursing usually lasts 7-9 months. Some farmer’s stock fingerlings directly to grow-out ponds and harvest the market sized fish. Other organized faring business usually performs series of nursing to maximise use of physical farming resources, the ponds. Grow-out of pangas is usually done either mono-culture or mixed culture basis. Fig. 45 shows a high density harvestable pangas farm in Mymensingh area.

Fig. 45. A high density harvestable panags crop in pond

Fig. 46. A high density harvestable panags mixed with tilapia in pond

Initially, mono-culture of pangas got popularity due to its fast growth high survival and

good feed conversion rates. However, high yield from a unit area creates high demand for supplemental feeds as pangas are scavengers and they do not utilize plankton foods naturally grown in fish ponds and excessively grow where fertilization and supplemental feeds are used. Soon, farmers discovered that mono-culture of pangas creates heavy plankton bloom that since they are not utilized by pangas it drops to the bottom completing its life cycle for about a week. The dropping of dead plankton to bottom of pond pollutes water and release of minerals by decomposition of dead plankton again creates an environment that allows more phyto-plankton to grow. Fig. 46 shows a high density panags and tilapia farming where both species showed high yield.

Though, there is a rough estimate of fish production in Bangladesh and fish landings from natural and farming sources but species-wise fish production from aquaculture/

farming is fragmentary and it appeared through the study that government statistics is out-dated and does not reflects rapid changes occurred in grass-root level specially in farming of panags and tilapia. Table 22 shows recorded production of tilapia and pangas in 2008-2209 and estimated production in 2009-2010 and projected production in 2015-2016. As shown in Table 22, estimated country-wide production of pangas in 2009-2010 is roughly 4 times higher than recorded production of 2008-2009 and that of tilapia is also 5 times higher than the recorded figure of a year earlier. As shown in Table 22, Dhaka division tops both in panags & tilapia productions followed by Rajshahi.

Table 22: Total estimated production of Pangas and tilapia in 2009-2010 and projection for 2015-2016*

Total fish Pangas Tilapia Pangas Tilapia Pangas Tilapia Dhaka 40570 130470 24410.7 6625.8 180,110 24290 270165 36435

• Division-wise figure for panags and tilapia till 2008-2009 were collected from Fisheries statistical yearbook based on districts.

Table 23: District-wise pond based pangas and tilapia production in Dhaka Division

Total fish Pangas Tilapia Pangas Tilapia Pangas Tilapia

Mymensingh 8353 29184 7617.0 29.2 73,500 1460 110250 2190

Table 23, shows recorded, estimated and projected production of pangas and tilapia for 2008-2009, 2009-2010 and 2015-2016 years, respectively in geographical distributions in districts of Dhaka division. As mentioned earlier, Mymensingh produces highest amount of panags in Dhaka division followed by Norshindi. Whereas Kishoregongj tops the list in tilapia production in the division followed by Norshindi.

Table 24 : District-wise pond basedpangas and tilapia production in Rajshahi Division

District ^Pond Production Production Production 2015-2016

area (ha)

2008-2009 (ton) 2009-2010

(Estimated)

(Projected)

Total fish Pangas Tilapia Pangas Tilapia Pangas Tilapia

Bogra 9477 26970 16,155.0 612.2 33,200 7,560 49800 11340 In Rajshahi division, Bogra tops the list among the districts in production of both pangas and tilapia followed by Naogaon and Pabna as shown in Table 24.

Chittagong division is not as prominent as of Dhaka and Rajshahi divisions in production of pangas and tilapia in the country as shown in Table 25. Combined production of pangas and tilapia in the division is around 5-6 thousands only. However, it was found that GOB statistics till 2008-2009 completely ignored Chandpur district where sizeable amount of tilapia are being produced through cage farming. By a current estimate roughly 3000 ton of mono-sex tilapia is produced in Chandpur by cage farming alone.

Table 25: District-wise pond based pangas and tilapia production in Chittagong Division

Pangas Tilapia Pangas Tilapia Pangas Tilapia

Noakhali 12332 35811 669.7 548.2 1,370 1,890 2055 2835

B. baria 8326 28215 2040.0 829.5 4,480 2,750 6720 4125

Chandpur* 3,000 5000

Total ₂₀₆₅₈ 64026 2709.7 1377.7 5,850 7,640 8775 11,960

* production through cage farming alone, faring area is not shown.

Table 26, shows that only two districts in the division out of 8 districts has significant amount of area under pangas and tilapia farming. However, out of two districts, Dinajpur has higher farming areas and higher production compared those with Gaibandha. Te northern part of Bangladesh that comprise newly formed division of Rangpur is reportedly short fish supply areas in the country and bulk of pangas produced in Bogra districts reportedly goes to districts in Rangpur division. Some key informant reported that Rangpur division has more prospects of pangas and tilapia farming as the districts in

the division is mostly placed on flood-free zone and land prices in these districts are reportedly cheap compared to other districts.

Table 26: District-wise pond based pangas and tilapia production in Rangpur Division

Pangas Tilapia Pangas Tilapia Pangas Tilapia

Dinajpur 10662 33659 905.4 818.0 1,620 3,180 2430 4770

Gaibandha 1844 5980 208.1 141.1 710 960 1065 1440

Total _{12506 39639 1113.5 959.1 2,330 4,140 3495 6210} Khulna division harbour biggest fish seed market place in the country but the market

place is mainly trade carp seeds of both local and exotic species. Anyway, three districts of the division produced roughly little over five thousand tons of pangas and nearly 8 thousand tons of tilapia as shown in Table 27.

Table 27: District-wise pond based pangas and tilapia production in Khulna Division

Pangas Tilapia Pangas Tilapia Pangas Tilapia

Jessore 6797 24761 463.0 996.4 1,650 3,200 2475 4800

Satkhira 3180 9008 736.9 1153.0 2,900 3,180 4350 4770

Jhenaidah 5011 16578 94.5 172.4 705 1,480 1057.5 2220

Total ₁₄₉₈₈ 50347 1294.4 2321.8 5,255 7,860 7882.5 11790 The production figure of pangas and tilapia in Sylhet division are shown in Table 24.

Among seven divisions in the country, only Barisal division so far reported to produce negligible amount of pangas and tilapia productions. Among other 6 divisions, Sylhet produces lowest amount of pangas and tilapia as shown in Table 28. There are 4 districts in Sylhet division and out of these 4 only 2 districts have notable pangas and tilapia farming. Sylhet division is famous for natural/wild fresh water fish production from natural depressions popularly known as hoars and wild fish are more favoured Sylhet compared to other divisions in the country.

Table 28: District-wise pond based pangas and tilapia production in Sylhet Division

Pond area

Pangas Tilapia Pangas Tilapia Pangas Tilapia

Hobigonj 3441 9087 673.3 357.1 1,295 1,495 1942.5 2243

As mentioned earlier, pangas and tilapia are exotic species and total biomass production from these two species are actually comes from farming, unlike most of other farming species where both wild and cultured stocks makes the landing. Besides, high density fish farming in the country is practiced using pangas and tilapia. And in most cases the

farming of these two species is done with supplemental feeds. Initially, home made mash feeds were popular due to its cost-effectiveness in low to mid density farming. However, farmers reportedly soon learned that in high density farming use of mash feed crates more water population and it causes diseases and currently, most farmers practicing high density farming uses commercial dry pellet of factory manufactured. The study found that roughly 30 commercial pellet feeds in the country is consumed by farmed tilapia and that of pangas consumes approximately over 60% of dry pellet feeds. Therefore, it was relatively easier to quantify total amount of pangas and tilapia biomass produced in the country based of production and sale of factory based dry pellets for fish and shrimp.

Table 29 shows estimated biomass production of pangas and tilapia in the country based on feed consumed in the country during 2009-2010.

%

As mentioned earlier, initially monoculture of pangas got popularity in the country when the species was first introduced in the country as farmed species. However, farmers soon

discovered that introduction of plankton feeding herbivore fish like carps and tilapia may control excessive growth of planktons and as they will strain plankton from culture water and will grow using plankton as its energy source. Therefore, commercial pangas farming currently uses pangas and mono-sex tilapia and other carp species as companion crop. The mixed farming of pangas and other specie/s performs two important tasks, it increases production of fish biomass without extra spending and companion species with pangas acts sweeper fish that clean excessive plankton growth. This combination truly acts as symbiotic where pangas gets clean environment due to cleaning by tilapia and/or carps and carps get plankton grown due to left over feed and excreta of pangas decompose to mineralize and enhance plankton growth.