2.1 Introduction
2.2 Inland Open-Water Fisheries
2.3 Productivity of Inland Open-water Fisheries
2.4 Exploitation
2.5 Management Programmes
2.6 Recommendations for Research Needs
The fisheries resources of Bangladesh have been divided broadly into inland and marine fisheries. The inland fisheries covers an area of about 4.3 million ha, while the area of marine fisheries is about 7 million ha-both producing about 0.95 million mt of fish annually. However, most of this fish production comes from inland fisheries resources totalling about 0.71 mt per year. This inland fish production constitutes about 72.1% of the total fish production of the country. The inland fisheries is again divided into open-water fisheries (capture fisheries) and closed-water fisheries (culture fisheries).
2.2.1 Riverine Fisheries
2.2.2 Floodplain Fisheries
2.2.3 Beel Fisheries
2.2.4 Kaptai Lake
The inland open-water fisheries of Bangladesh includes rivers (including estuaries), canals, beels, floodplains, Sundarbans and Kaptai lake. All these waterbodies cover an area of 4.05 million ha, which is about 94% of the total areas of the inland fisheries of the country.
Bangladesh possesses about 230 rivers including their tributaries. The three main rivers of the country viz., Padma, Meghna and Jamuna-Brahmaputra and their tributaries cover an area of 1.03 million ha, which constitute about 25.49% of the total inland open water area. During monsoon, annual flooding of the rivers inundate 70% of the total land surface (Rahman, 1985).
Floodplain fisheries are the areas of relatively low-lying flat land annually inundated by the over-spill of adjacent rivers, lakes and natural depressions during rainy season. Bangladesh possesses extensive floodplains along both sides of the river courses. The area covered by the flood plain is about 2.8 million ha which comprises about 69.99% of the total inland open water area.
Beels are low-lying natural depression-like small lakes located in floodplain regions. The total area of beel is about 1.14 lakh ha which constitutes about 2.82% of total inland open water area. These beels remain submerged for about 4-6 months during rainy season. There are two types of beels viz., the seasonal beels which dry-up annually and the perennial beels which retain water round the year.
The Kaptai lake was impounded in 1961 by constructing a dam across the Karnaphuli river at Kaptai of Rangamati Parbottya Zilla. The primary purpose of this lake is to generate hydro-electric power. The area of this lake is about 68800 ha comprising about 1.7% of the total inland open-water fisheries.
The open-water fisheries is the most important fisheries of the country which alone produces about 0.48 million mt annually. It contributes 50.4% to the total fish production of the country and 68% to the total inland fish production.
Floodplain fisheries alone shares 61.53% of the total inland open-water fish production. It produces about 2.95 lakh mt. Next to floodplain fisheries, river fisheries and beel fisheries occupy successive position (Table 1).
Table 1 Productivity of different types of inland open water fisheries and their percentage contribution to total production.
|
Name of waterbodies |
Production Total (mt.) kg/ha |
% Contribution | |
|
Rivers including estuaries |
5 124,843 |
121 |
26.02 |
|
Sundarban |
6,297 |
|
1.31 |
|
Beels |
49/201 |
431 |
10.26 |
|
Kaptai lake |
4,216 |
61 |
0.88 |
|
Flood lands |
295/185 |
104 |
61.53 |
|
Grand Total |
479,742 |
119 |
|
Source: DOF (1991-1992)
However, with respect to productivity, beel fisheries occupies the highest position which is about 431 kg/ha. Next to beel fisheries, river and floodplain fisheries occupy the successive positions with respect to productivity (Table 2). But in Kaptai lake the lowest productivity had been recorded. However, fish production as recorded by the FRI Scientists in the beels of the 3rd Fisheries Project areas varied from 274.7-865 kg/ha.
Meghna, Padma, Jamuna and Brahmaputra are the principal rivers of this country. Among these rivers, Meghna plays dominant role over other rivers both in respect of productivity and production. It alone contributes 11.30% to the total inland open-water fish production with per hectare production of 1369.60 kg. After Meghna, Jamuna and Padma occupy the successive positions. Fish production in Brahmaputra river is not significant (Table 2).
Table 2 Production of principal rivers and their percentage contribution to total inland open-water production.
|
Name of the river |
Area of river (ha) |
Production |
% Contribution | |
|
|
|
Total (mt.) |
kg/ha |
|
|
Meghna |
73999 |
54244 |
1369.60 |
11.30 |
|
Padma |
69481 |
1641 |
50.6 |
0.34 |
|
Jamuna |
73666 |
2253 |
30.58 |
0.46 |
|
Brahmaputra |
- |
391 |
- |
0.081 |
Source: DOF (1991-1992)
During dry seasons, the fishes of different species get concentrated in great number in the permanent waterbodies along with the receding of flood water. This provides an excellent opportunity to exploit them as much as possible. This causes heavy mortality to fish every year. But there is hardly any study on the fish and prawn population and their stock assessment. Consequently, it becomes hard to relate overfishing to the causes of stock declination. However, a few studies on the exploitation of fish population have been made.
Tsai and Ali (1985) had carried out a study on open-water carp fisheries management. They recorded a decline in Padma/ Brahmaputra and upper Meghna stocks of major carps. According to them the reasons for decline are construction of embankments, sedimentation and overfishing for Brahmaputra stock and Farakka barrage, embankments and over fishing for Padma stock, while for the Meghna stocks, overfishing was identified as the main cause.
Tsai and Ali (1987) also recorded overfishing in major carps of Sylhet-Mymensingh basin.
BCAS (1989) reported the mortality and rate of exploitation of hilsa, Hilsa ilisha of Narisha-Padma fishery, Nayabhangni fishery and Meghna fishery.
BCAS (1989) recorded maximum fishing mortality of H. ilisha in Nayabhangni fishery (0.89/year) and lowest of it was recorded in Meghna fishery (0.33/year). The rate of exploitation values recorded in Narisha-Padma fishery (0.64) and Nayabhangni fishery (0.57) were above optimum exploitation level which is about 0.50. But its value as recorded in Meghna fishery was 0.31 which indicated some degree of under fishing in this fishery. Whereas the rate of exploitation of H. ilisha reported by Rahman (1992) is 0.518 and the size of first capture (Lc) is 35 cm. This value is just slightly above the optimum value. The total mortality, fishing mortality and natural mortality values as recorded by Rahman (1992) were 2.411, 1.246 and 1.162 respectively. All these values are higher than the values recorded by BCAS (1989). In Narisha-Padma and Nayabhangni fisheries the present exploitation rate should be reduced for obtaining sustainable yield of fish.
The fish production in the major rivers viz., Meghna, Padma, Jamuna and Brahmaputra have declined greatly. Within 8 years (1984-1992), the fish production has been decreased by about 89.69% in Brahmaputra, 84.35% in Padma and 65.98% in Jamuna. The decline in Meghna (23.38%) is relatively low as compared to other rivers. This may be associated with more or less stable catch of the hilsa fish which comprises highest landing of fish from this river.
To know the present fishing status and fishing intensity as compared to last 8 years position the fishermen and middlemen were interviewed in the fishing spots as well as in the landing sites. About 99.2% of the fishermen reported a decrease in their catch. The average decline of their catch was 41% . Almost all the fishermen and middlemen stated that fishing intensity and fishing unit had been increased by about 37.4% and 33.7% respectively (Table 3).
Table 3 Opinion of fishermen regarding the present status of catch, fishing unit and fishing intensity as compared to last 8 years.
|
Particulars |
Fishermen opinion (%) |
Average | |||
|
|
Same as before |
Increased |
Decreased |
Increased |
Decreased |
|
Status of fish catch |
0.8 |
- |
99.2 |
- |
41 |
|
Status of fishing unit |
5.7 |
94.3 |
- |
37.4 |
- |
|
Status of fishing |
- |
100 |
- |
33.7 |
- |
|
Intensity |
|
|
|
|
|
Source: Present survey
All middlemen are of the opinion that the catch of the fishermen has decreased and reduction is about 44.6% by average (Table 4).
Table 4 Opinion of the middlemen regarding the present status of catch, fishing unit and fishing intensity as compared to last 8 years.
|
Particulars |
Middlemen response |
Average (%) | |||
|
|
Same as before |
Increased |
Decreased |
Increased |
Decreased |
|
Status of fish catch |
- |
- |
100 |
- |
44.6 |
|
Status of fishing unit |
- |
100 |
- |
41.3 |
- |
|
Status of fishing |
- |
100 |
- |
48 |
- |
|
Intensity |
|
|
|
|
|
Source: Present survey
Most of the fishermen (77%) and middlemen (71%) have also stated that the size of the fishes are now smaller than before (Table 5).
Table 5 Fishermen and middlemen views on the present size of the major species of fishes as compared to last 8 years.
|
Particulars |
Fishermen views (%) | |||
|
|
Same |
Smaller |
Much smaller |
Bigger |
|
Fishermen views |
11 |
77 |
9 |
3 |
|
Middlemen views |
9 |
71 |
20 |
- |
Source: Present survey
Due to adverse effects of overfishing and of FCDI Projects, some of the important species are reported to have either become extinct or at the verge of extinction. These species are, Labeo nandina, Tor tor, Tor putitora, Channa barca, Channa punctatus, Bagarius bola, Bagarius bagarius, Rita rita, Puntius ticto, Silonia silondia, Eutropiicthys vacha, Scatophgus, Scatophgus argus, Labeo pangasia and Pangasius pangasius.
However, from all the above statements it can be concluded that the fish exploitation rate has been increased by now than before. The serious decline of fish stock in the major rivers has created an alarming situation for the sustainable fish production in rivers and other waterbodies.
2.5.1 Revenue Oriented Management System
2.5.2 New Fisheries Management Policy
2.5.3 Rehabilitation of Water Bodies and Other Development Programmes
To mitigate the losses and augment the fish production in inland open-water fisheries, the Government of Bangladesh has undertaken some management programmes on open-water fisheries. The old and existing programmes are described briefly.
The revenue oriented management system is an old system in which the open-water bodies are leased out segmentally either to the fishermen or to the middlemen for a period of 1-3 years. This traditional leasing system is much more revenue oriented which ignores the welfare of the fishermen as well as resource development. In the existing leasing system of the waterbody, the genuine fishermen are deprived from their fishing rights as they cannot compete in the bidding processes with the wealthy middlemen. To secure fishing rights, the fishermen are to pay money or a share of catch to the lease holder. Due to short term nature of the leasing systems, the lease holders do not derive any incentive to undertake conservation measures, rather they harvest fish as much as possible for obtaining maximum benefit.
To overcome the problems of existing leasing systems the Government has introduced new fisheries management policy. The main objective of this system is to free the fishermen from exploitation by the middlemen lease-holders by eliminating them through licensing system to genuine fishermen and to ensure better conservation of fish resources. The new policy has been implemented on a pilot-scale basis in May, 1987 in 3 selected areas representing the various types of waterbodies of Bangladesh. Bangladesh Centre for Advanced Studies (BCAS) has been conducting monitoring activities of these management programmes.
The monitoring team stated in the final draft report that the new licensing system has markedly increased the relative economic gain to the fishermen of the DOF managed riverine, baor and baor fisheries.
To improve the fish production in open water on a sustainable basis Govt. has undertaken two rehabilitation programmes viz., beel nursery programme under 2nd Aquaculture Development Project and fingerlings stocking programmes under Third Fisheries Projects. Under these rehabilitation programmes stocking of 3-5 days old hatchlings of major carps in the beels of old Sylhet and Mymensingh districts was started from 1992 and about 584.56 kg of hatchlings were stocked during 1994. The results obtained were reported to be not so satisfactory. The fingerling stocking programme was started in 1991 and about 417.85 tons of fingerlings were stocked in 1993 in 5 beels (Chanda, BSKB, Gorali, Halti and Hilna) of Natore, Khulna, Gopalgonj districts. The results obtained were reported to be quite satisfactory.
Besides, Government has also undertaken an integrated fisheries development project in flood control, drainage and irrigation project areas. But it is still in infant stage and only 17 farmers were alloted khals and borrow pits in Chandpur irrigation project for pen-culture very recently.
Several researches have been done on the culture fisheries in the country, specially on pond fish culture by different workers. But very few researches have been carried out on the inland open-water fisheries by the scientists of different institutes. Most of these works were on the biology and taxonomy of fishes. There is hardly any research work on the fish population dynamics, stock assessment, fish migration, bio-diversity, species diversity, fishing technology and limnology of waterbodies. Most of these researches were carried out by the scientists of different institutes sporadically. The Fisheries Research Institute (FRI) was established to carry out researches more systematically and precisely. The Riverine
Station of the FRI has been conducting researches on open-water fisheries since its inception. By this time, this research station has completed seven research projects and made significant achievements. At present, it has seven on-going projects and has proposed eight new projects for the next five year plan. However, the following recommendations are made for obtaining sustainable yield from open-water fisheries.
i) Research should be carried out on the stock assessment, population dynamics and exploitation rate of commercially important fishes specially hilsa, major carps, catfishes and shrimps for their effective management.ii) Studies should be carried out on the limnology of different types of inland open waterbodies such as rivers, khals, canals, beels and floodplains.
iii) Studies should be carried out on the toxic effect of different industrial effluents and pesticides to fish and other aquatic organisms.
iv) A research programme should be undertaken to assess the impact of FCD project on fish, other aquatic organisms and ecology of fish habitats by comparing all these parameters just before and immediately after the completion of the projects.
v) Studies should be carried out on the species composition of different types of open-water habitats to identify the species which are at the verge of extinction and to suggest measures for their propagation through artificial means.
vi) Studies should be carried out on the biodiversity of different types of open-water habitats.
vii) Researches should be conducted on the migration and stocks of Hilsa ilisha to determine its route of migration, types of migration, seasons of migration and migratory circuit of its different stocks.
