Why unbridled aquaculture in East Godavari district needs to be monitored

Impacts of aquaculture need to be assessed from a more comprehensive value-chain perspective instead of a narrow production focus

By P V Krishna, Charudutta Panigrahi
Published: Monday 07 June 2021

The East Godavari region is a huge fish tank and a prosperous showcase of the Blue Revolution. The scale is overwhelming — with 13 coastal mandalas spread across a coast line of 161 kilometres, aquaculture is actively practised in more than 17,000 hectares (40,000 acres).

This supports as many as 400,000 fishermen backed by 650 and more fishermen cooperatives.

East Godavari district alone is home to a third of the hatcheries in the country. One can imagine the livelihoods generated by such a mega-scale vocation. Livelihoods bring to focus the significant role of ponds in meeting broader nutritional security needs as well as its importance in local and more extended value chains.

Such is its lure that agriculture is furiously converting into aquaculture in the district. Paddy cultivation is giving way to fish-rearing. More farmers are venturing into aquaculture. 

Over 30 per cent of aqua production is exported to foreign countries while the rest meets domestic demand. Paddy cultivation does not yield expected returns to farmers; the lush green paddy farms are hence fast turning into fish tanks.

The novel coronavirus disease (COVID-19) stalemate has dealt a severe blow to the industry and the stakeholders; the owners of hatcheries and feed firms are sceptical about their future. Any more delay in the resuscitation of the aquaculture activity may lead to a complete collapse of the industry.

But it is also the right time to bring about changes in our understanding of the interrelationships between aquaculture and poverty. There is a growing realisation across sectors and geographies that the impacts of aquaculture need to be assessed from a more comprehensive value-chain perspective rather than through a narrow production focus.

It is no more relevant to view the practice as a targeted intervention to alleviate poverty. It is posing a serious threat to agriculture because the discharges from the fishponds are being released into the nearby paddy fields. Salt water is used in aquaculture, so the ground water gets saline in the entire area.

The importance of aquaculture development as part of the measures to mitigate water scarcity and to support sustainable intensification of food production generally is under cloud. The development of appropriate safety nets for the poorest groups cannot be done risking the entire ecological sustenance of a large, progressive region like East Godavari.

It is accepted that the NEERI (National Environmental Engineering Research Institute) report has opined that aquaculture is a source of severe nutrient pollution and over a period of time this has the potential to destroy the entire aquatic ecosystems, as nutrient wastes are discharged directly into the surrounding areas and waters.

It states:

“For every ton of fish, aquaculture operations produce between 42-66 kilograms of nitrogen wastages and 7.2-10.5 kilograms of phosphorus wastes.”

Since intensive aquaculture necessitates large quantities of fresh water, pumping ground water in coastal areas invariably causes saltwater to ingress into aquifer and contaminate the underground reserves. Salt water can percolate into surface water bodies, sub-surface water reservoirs, canals, etc.

The unchecked sucking of ground water depletes water tables and contributes to the desertification of the area, gradually but steadily. Salt water stored in the ponds gets mixed with ground water. This causes widespread soil and water salinity, thereby damaging the land and water sources.

This would aggravate poverty inter-generationally. The negative environmental impacts of aquaculture include water eutrophication, water quality, alteration or destruction of natural habitats; introduction and transmission of aquatic animal diseases. The excess feed and faecal matter sedimented in the pond gets ammonified, which leads to excess ammonia formation in water.

Microbial diseases kill the fish and spoil the water. Agricultural production in the area also suffers.

Local aquaculture farmers need to be sensitised about the negative impact of unbridled, unmonitored aqua-farming. No one can deny the benefits of aquaculture, which include an increase in food production and highly remunerative economic returns and profits. But we need to be cognisant of the side effects that devastate the ecology.

We need to minimise the negative impacts, rather than just prohibiting the activity. Livelihoods should take care of the environmental health and it is possible to achieve a sustainable aquaculture. The strategies should be supported and practised by the farmers, the civil society and all of us.

The process should start by defining “sustainable” aquaculture. Aquaculture techniques, like the different closed-system technologies, including re-circulating tanks, raceways and flow-through systems would reduce the harm.

The water should be treated before discharge without any fish escape. Open pens are not sustainable. The problems of fecal waste, predators’ interaction, alienation of non-native / exotic species, excess inputs (food, antibiotics), habitat destruction, disease transfer continue in the pens.

The Union government should provide special incentives / grants to projects that focus on expanding and improving the way the fish is farmed sustainably. There is a lot of handholding the capacity building required for the aquaculture farmers.

Aquaculture (prawn ponds) started in Nedunuru, a village in East Godavari district of Andhra Pradesh, about a decade ago. In the last five years, it has proliferated, and the scale has multiplied manifold. We observed the following drastic changes in the area (this is intuitive and experiential and not backed by any scientific study)

  • An intolerable increase in humidity.
  • A decrease in the production of coconut owing to a new disease
  • A dwindling paddy production (it was a paddy-intensive area)
  • Daily labourers depending on agriculture have lost their work and are now jobless or not gainfully employed
  • Shrinking ground water levels
  • Abnormal increase in PH of drinking water observed in tests conducted by the panchayat
  • Blood pressure and blood sugar abnormality in youth identified recently in the village
  • Certain varieties of fish — such as Mattagidasa, Goraka, Koramenu, Marpu, Ingidayi, Bommidaayi, etc — have disappeared from the local water. They were naturally available in the canals in olden days a decade ago. They are no longer seen.

It has come to light that local authorities many a time pass off prawn fields as paddy fields, even as applications for aquaculture have been turned down by the government. It has become more evident that the local economy is going downhill due to aquaculture and the lure of quick gains and profits is destroying the habitats and the food security system.  

If aquaculture continues unbridled in the area, a day will soon come when nothing else will grow. Excess of everything is bad. Excess of aquaculture has started killing families and perpetuating poverty through generations.

It’s time we act.

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