DR. V.R.P. SINHA
Senior Specialist, FAO/UNDP BGD/89/012
The man made modifications in water courses especially through flow control structures and in land profile through reclamation for agriculture, human settlement, construction of roads, have rendered the fragile aquatic ecology most vulnerable, leading to soil erosion, pollution, loss of mangrove, forests and aquatic bioproductivity.
The developmental activities, whether they are concerned with water resource or agriculture or industry or flood control or navigation improvement, all conflict considerably with fisheries. While, man made lake, diking of sea and river banks bring abrupt change in aquatic ecology, large scale earth moving, clearance of forest, and importation of migrant labour disrupt partly or wholly the whole ecosystem. Drainage of natural fish producing areas like wetlands, swamps ponds, pools and puddles reduces and affects flood plain fisheries. Intensive agriculture or agricultural related industries producing pesticide, fertilizers, oil, animal feed discharge directly or indirectly harmful waste materials to the aquatic ecosystem. Urban and municipal wastes are also detrimental to the aquatic resources.
The water resource development projects bring change to riverine to lacustrine ecosystem with concomitant increases in turbidity, organic content and oxygen limit, which affect the survival, abundance and distribution of the upstream and mainstream fish. Reduction of preferred habitat, shelter areas, suitable spawning sites and also of reduction in fish food species such as riverine insects, molluscs and other invertebrates affect the biological performance of the fish. The upland tributary fish suffer most, because of isolation particularly in dry season.
Watershed modification particularly forest manipulation involving removal of tree disruptes the protective cover of the soil resulting in the alteration of stream flow, increased upstream erosion, turbidity of water, siltation down stream and increased water temperature and its fluctuation and also salinity. While increase in the velocity of streams results in dislodging of fish eggs and benthic organism, deposits of silt in the spawning areas suffocate eggs, embryos and young fish. High turbidity causes inflammation of the gill and kill young fish. Silt provides ideal substrate for bacterial growth and bacterial infections flares up in water with heavy silt. Similarly rise in temperature increases the fish pathogens and also increases the rate of eutrophication. Temperature fluctuation affects life history of the fish and has adverse affect on their survival, growth and feeding.
Looking at the other side of the story, the fish originally considered as environment friendly and even helping in upgrading soil and water is now regarded by many as disruptive because of intensive cultivation. Recent global surge and emerging opportunity of fisheries resulted in intensive cultivation of fish indiscriminately in fresh, brackish and sea water without giving much consideration to the environmental issues. Intensive aquaculture practised primarily involves increasing use of energy, formulated feeds, fertilizers, pesticides and disease control chemicals, besides water exchange. All of them may adversely affect aquatic environment. Also, the fast expansion of aquaculture in coastal area has caused interest conflicts and, probably, adverse social environmental impact.
As a result of blocking tidal seawater access by farm dikes and roads, mangrove forest has been degraded with consequent loss of biological diversity such as waterfowl, reptiles, estuarine invertebrates and fishes. Overharvest of postlarvae shrimp and incidental capture of larval or fry stages of other species are expected to result in depletion of nearshore fishery stocks. Salinization of agricultural land becoming serious problem as a result of conversion of such land to shrimp ponds. As a result of drainage of enriched effluent water from shrimp ponds, coastal water is getting entrophic with increased BOD. Large-scale mangrove conversion in many countries has also displaced rural communities which traditionally depended on mangrove resources for their livelihood and reduced the range of goods and services produced from the mangrove forests.
Land subsidence in Taiwan Province has occurred by excessive pumping of groundwater for shrimp and eel culture. This has resulted in salinization of underground water and land due to salt-water intrusion ultimately affecting agricultural productivity, and reducing freshwater-supply.
Because of fish farming, disturbance to wild life and their habitat destruction have been reported from many countries. Cormorants descend on shrimp farms in large numbers, consume 100– 200 grams of shrimp per feeding over six to eight feedings per day, and thereby cause considerable financial loss. Cormorant populations have increased as a result of fish farming in Germany. In Latin America most shrimp farms employ crews of full-time cormorant hunters who kill hundreds of these birds per month per farm. There is no reason to believe that this scenario will not occur in future here as it has occurred worldwide. Faced with economic losses of the proportions described and unless otherwise informed, the shrimp farmers will not bother with taxonomic distinctions, and will simply hose any bird that is in the vicinity of their pond.
While the public health consequence of red-tide outbreaks in areas where shell fish are grown are well known, the epidemic outbreaks in fish have become a common phenomenon because of general environmental degradation. While, Norwegian cage fish farming industry was hit by Hitra disease, milkfish culture in Philippines, Laguna de Bay, crashed entirely due to excessive organic load resulting from over crowding of fisheries in an area with insufficient tidal exchange.
Taiwan tiger prawn exports declined from about 90,000 ton to 18,000 tons in one year due to disease epidemic. Similarly Equador shrimp culture production dropped from about 55000 tons to 43000 ton a year due to disease. The most devastating outbreak of epizootic ulcerative syndrome affected the intensive snakehead and catfish culture in Thailand in 1982–83 with a loss of approximating US$ 8.7 million in one year. Similarly Bangladesh suffered loss from EUS in 1988–89, resulting in reducing price of fish up to 75%. Similarly Australia, Indonesia, Malaysia, India, Nepal and Srilanka also suffered the serious setback.
The above account shows the gravity of the situation. Therefore, the training programme has been intended to focus the issues and problems caused by other development activities to fisheries and vice versa both at the physical/material level and at the societal level.
It is hoped that developmental projects shall take due care to mitigate any deleterious environmental impact through monitoring and evaluation of the environmental changes at regular intervals. But it is necessary for all of us to understand the impact, and intricacy and identify suitable corrective measures, wherever necessary. I sincerely hope that the deliberations in the training programme will enable the participants to understand the width and depth of issues confronting us to have sustainable development of fisheries resources of the country without impairing the environment.
ADDRESS BY PETER MYERS, FAO REPRESENTATIVE, DHAKA
We have seen increasing emphasis on environmental issues and on the need for sustainable development in recent times and it is noteworthy that the environment is also strongly on the agenda of the Fisheries Research Institute as evidenced by Seminar/training course. In the context of the fisheries sector, environmental issues are, of course, very diverse and very complex and solutions to many of the problems call for political decisions and for strong community and public support as well as for technical and economic inputs.
Fortunately there are now somewhat brighter prospects in most countries and around the world that such political and community commitment may be more strongly forthcoming in future than it was previously as we are now, all of us, very much more aware of environmental issues. A 100 years ago, towards the end of the last century when fisheries scientists first started to investigate fisheries resource management, the phrase ‘sustainable development’ had not been coined and even up until the middle of the present century there was very little public awareness of the concept of sustainability especially as far as fishing was concerned. Until quite recently, to the laymen and even to the amateur fisherman, fisheries resources were largely regarded as being renewable and almost unlimited.
Since then, public awareness has been considerably heightened. Firstly, a few years ago the report of the Bruntland Commission sharpened our perception of sustained development and sustain resource use and more recently the world-wide participation in, and publicity given to, the UN Conference on Environment and Development (UNCED) held last year in Rio de Janeiro represented a major international landmark as far as world environmental issues are concerned.
As scientists and colleagues involved in the natural resources sector, many of you here will have followed those deliberations closely as well as being aware of the actions being taken to implement the UNCED recommendations particularly under the Agenda 21 programme. You will be aware therefore of the subsequent UN General assembly decision to establish under ECOSOC a high level Commission on Sustainable Development in order : to ensure an effective follow up to UNCED, to enhance international cooperation and to monitor progress in the implementation of Agenda 21 at national, regional and international levels. The 53-member Commission - which includes representatives from 11 Asian countries - will work closely with NGOs as well as with the governments of UN member countries and the work of the Commission will encompass a comprehensive agenda within which it can be expected that fisheries will be given appropriate priority. A high level board of eminent persons will advise the UN Secretary General on matters of sustainable development and on the issues and themes to be addressed by the Commission on Sustainable Development. FAO and other appropriate UN agencies will participate in an Inter Agency Committee on Sustainable Development which has been set up to act as the Secretariat for the Commission.
Parallel to these more recent UN System developments and more specifically related to marine fisheries, building further on the groundwork established by the UN Law of the Sea Convention and the FAO World Fisheries Conference in 1984, international meetings were held last year on responsible fishing and High Seas Fishing and there is strong consensus to carry these and similar initiatives forward.
We can be hopeful, I think, from these developments at international level that there is a sufficient weight of public and political concern that nations of the world are taking environmental issues seriously and are establishing new and stronger mechanisms to monitor environmental development and to promote programmes which balance the needs of development with the need for conservation and environmental protection.
Action and arrangements at the international level cannot however of themselves achieve the desired results in terms of sustainable production and an optimal environmental balance. National commitment and national programmes are required to galvanise public awareness and to promote responsible action by the community and also, and importantly, at the level of the individual. The situation is particularly complex in Bangladesh where the concept of fisheries as an ‘open access’ resource is inextricably linked with poverty alleviation issues.
Mr. Chairman, there are a host of technical and economic problems related to sustainable fisheries production in Bangladesh that will doubtless be addressed during this training seminar and I certainly don't need to itemise these. In the marine sector I am thinking of the need for better information and statistics through more comprehensive and periodic resource surveys; the need for effective management of artisanal fisheries; for integrated coastal area management and for the utilisation of by-catch. These are but a few. In the inland fisheries sub-sector there is need for water quality studies and monitoring; protection of breeding grounds and control over the catching of immature or breeding stocks; participation - in fact, local leadership-of user-communities in fisheries management as well as the much publicised issue of the impact of flood control, drainage and irrigation projects. FRI has a valuable contribution to make on all of these issues and I am sure this training workshop will yield useful results. In addition to addressing the technical and economic factors involved I would urge, however, that due consideration also be given as to how FRI should collaborate and cooperate with other agencies concerned with the environment and what methods and mechanisms are needed in order to bring practical solutions and improvements which are acceptable to, and can be adopted by rural communities and individual fisherfolk.
