The Hindu : Kerala / Thiruvananthapuram News : Wetlands under threat, warns expert

Online edition of India's National Newspaper
Thursday, May 10, 2007
ePaper

Kerala

Kerala - Thiruvananthapuram

Wetlands under threat, warns expert

Special Correspondent

Several stretches of the backwaters polluted by organic, industrial effluents

`Protection of wetland systems will benefit country's economy' Need to develop database on endangered, endemic species of fish

Thiruvananthapuram: A considerable area of the backwaters in Kerala has been lost due to reclamation for agriculture, mining, urban area development and other activities, a study on the faunal biodiversity of selected wetland ecosystems of Kerala carried out by S. Bijoy Nandan, Reader, Department of Marine Biology, School of Marine Sciences, the Cochin University of Science and Technology, has revealed.

The findings of the study, presented at the ongoing Kerala Environment Congress 2007 organised by the Centre for Environment and Development (CED) here, calls for strict regulations on encroachment and reclamation of wetlands in the State.

The study report states that man made and natural calamities such as the tsunami had considerably eroded the biodiversity in the `kayal' and riverine wetlands. Several stretches of the backwaters are polluted by organic and industrial effluents.

Biological methods

It proposes biological methods to control pollution and purify the water and regulations on the use of river systems for human needs. Highlighting the devastation of rivers caused by sand-mining, it calls for the development of alternate materials to substitute river sand.

The paper also stresses the need to apply modern methods of coconut husk retting to free the backwaters from organic pollution.

The report calls for developing a database on endangered and endemic species of fish and other wetland organisms. It underlines the need to employ cryopreservation techniques and captive breeding and seed production for the propagation and conservation of threatened species of fish. Mr. Nandan has recommended restrictions on fishing to conserve fish species found in backwater systems. Except for stake nets, there is no proper registration of the fishing gear or craft.

The registration system under the Fishermen Welfare Board is not effective as a regulatory mechanism. Indiscriminate fishing can be controlled only by strict registration and licensing for all fishing craft, gear and fishermen, he points out.

Restrictions

The report also recommends restrictions on the mesh size of stake nets, Chinese dip nets and dragnets used by inland fishermen to ensure better protection for juvenile fishes.

It calls for close monitoring to deter the use of purse seine nets by fishermen during the trawling ban period. Stake nets should be deployed only during the receding tide, it proposes.

The study proposes the deployment of fish aggregating devices to enhance the natural recruitment of fish stock in the wetlands. It also recommends establishment of broodstock maintenance centres and hatcheries for conservation of endemic and critically endangered fishes. The report calls for discouraging the introduction of exotic species of fishes in open waters and dams for resource augmentation. It emphasises the need for scientific studies to assess the impact of exotic species on local varieties of fish.

Mr. Nandan also recommends the utilisation of reclaimed paddy lands in Kuttanad and Kattampally to raise an additional crop of fish during the fallow season.

The rivers and lakes are biological hot spots and are to be protected as a bioreserve, sanctuary or ecologically sensitive zone. Efforts should be made to curb human intervention in natural habitats and strict regulations should be enforced on the introduction of exotic species in rivers and lakes.

The Kerala River Protection and Water Conservation Act and more stringent laws should be enacted to ensure the complete and integrated protection of the wetland ecosystems, the paper adds.

In his presentation at the congress on Wednesday, chairman of the Kerala Biodiversity Board V.S. Vijayan said the protection of wetland systems would benefit the economy of the country in the long run.

"While one hectare of forest is valued at Rs.1 lakh, the value of a hectare of wetland is Rs.7 lakh," he said.

Eighteen young scientists will present their papers at the congress on Thursday. An open forum on the protection of the Vellayani Lake will also be held. Planning Board vice-chairman Mr. Prabhat Patnaik is scheduled to inaugurate the valedictory.

Printer friendly page
Send this article to Friends by E-Mail

Kerala