This article has been written from inputs provided by Dr. K. Rajarathnam and Dr. P.J. Sanjeeva Raj of CReNIEO, Madras. The project on ‘Artificial Reefs’ is being fully funded by UNDP-GEF/Small Grants Programme. Development Alternatives is the National Host Institution for the S.G.P.

The fish stock in coastal waters is grossly depleted and the biodiversity imperilled due to over-exploitation by mechanised bottom trawling. The fishermen communities living along the coast had all along been poor, but they have been managing to survive till recent times at great risk to their life everyday braving the weather and the sea. They understand the sea, have great respect for the waters and their skills and techniques are passed on from one generation to the next to sustain themselves through ages. Within a community also, the income level is variable. Some can afford catamarans and nets, but some have to depend on the line and hook catches they can make. For this latter category, the fish stock in the shallow coastal waters is of vital importance. The fishermen communities along the Coromondel coast have built up knowledge and expertise on an amazing range of artificial fish habitats and fish aggregating devices. Necessity has always driven mankind to innovate and improvise!

Traditional Artificial Fish Habitats

The artificial devices are made from available resources – branches of trees weighed with anchors, are dumped into the sea by fishermen which act as artificial reefs called mullam. Hook and line are used to catch fish from such artificial reefs. Coconut fronds, tied at 1m intervals along a rope, arranged to resemble a bottle – brush are suspended from a float and anchored at seabed with a weight are called kambi and serve as fish aggregating devices. The harvesting is done by four catamarans from four directions using a square lift-net. One species of tree gets preference over all others – the ‘Tigerbean’ tree or ‘Delonixelata’ since its bark when rotted in seawater emits a foul stench that attracts fish in large numbers. Chemical analysis of this bark yields the aminoacid L-asparagine, aspartic acid and sucrose acetate which are all recognized as fish attractants. 

All these green vegetation and trees are bio-degradable, albeit eco-friendly, but not easy to access anymore. The created ARS are perishable and their replacements involve expenditure. There is scope for application of some modern day technology to create these ARS on a more permanent basis.

Modernizing the Traditional Artificial Reefs

Currently, a project is being executed by the Centre for Research on New International Economic Order, Madras, to create ‘artificial reefs’ at a depth of 20 to 25m a few Kms into the sea with participation of the fishermen of the village Periya Neelanganai Kuppam, about 25 kms south of Madras.  The aims of the project are:

q	To restore and enhance the biodiversity around an artificial reef in coastal waters.
q	To promote fish aggregation around the reef, ensuring at least sustenance fish catches for the poorest of the poor fishermen who can only afford a hook and line, and
q	To provide or to promote breeding sites for the seafood organisms like cephalopods and fish and to replenish the fast depleting inshore fisheries.

 

Methodology

q	The ‘Artificial Reefs’ are being created with concrete modules – 200 concrete well rings of 60 cm dia and 30cm height at a depth of 20 to 25 meres.
q	The ARS are to be treated as common property resources
q	Fishing is to be open to all fishermen by hook and line technique only.

Every month, one module would be hauled out of the sea to study the ecological succession of the biofouler communities encrusted on to its surface. The biodiversity, their distribution patterns, densities and populations would be studied.

q	Through the fishing data at the reef, the diversity of fishes that are attracted to the reef, the food chains established, their seasonal fluctuations, and the reproductive cycles of all the reef communities would be studied.
q	The breeding potential of the reef communities would be studied through collection of fish fry and fingerlings at the reef.
q	Above all, the fishery enhancement in the inshore waters, between the reef and the shoreline at the fishing village, would be studied through fish catches to assess the biodiversity enhancement that the reef would have contributed to.

 

Present Status

The artificial reef has been launched in mid – August. Experimental modules numbering 12 have also been placed in position. Every month one of these modules will be pulled out of the depths and studied for the ecological succession of the biofouler communities, their settlement patterns, densities, population and species composition etc. The reef will be opened for fishing (hook and line) in two months time.

Fishermen’s Tale

CReNIEO reports sighting of a 6 metre ‘tiger shark’ in the vicinity of an earlier artificial reef set up for the fishing community. Apparently, the shark has plenty to feed on around the reef thereby confirming the establishment of a new food chain with a ferocious predator on top! Right now, the problem is how do the poor ‘hook and liner’ fishermen get their catch. The laws of nature should enable co-existence of shark and man at respectful distance from each other.

Educational Resources on Sustainable Development and the Global Environment

A broad range of up-to-date educational resources and other information on critical global environmental issues is now available on the World Wide Web from the Environmental Education Project of the World Resources Institute. Created for high school and college educators worldwide, WRI’s Environmental Education Site features innovative teaching materials, background information on sustainable development and related topics, and news about the field of environmental education. Included in the site are:

q	Fifty down-loadable colour maps and graphs depicting global environmental conditions and trends in the areas of population, deforestation, and many other vital topics.
q	Sample student activities from WRI’s eleven “Teacher’s Guide Units” on essential global issues including biodiversity, population, energy, oceans, and women in developing countries.
q	Links to major environmental education sites
q	Links to in-depth information and materials on sustainable development from World Resources Institute, the United Nations, President’s Council on Sustainable Development, and other authoritative sources.

Recognizing that teachers play a key role in fostering a sustainable world, WRI created its Environmental Education Site to help educators around the world gain access to innovative, up-to-date, and authoritative supplement teaching tools and other information on the complex environmental, economic, and social conditions that are shaping our future. WRI’s Environmental Education Project, established in 1992, works to incorporate environmental education into mainstream curricula, develop high-quality instructional materials on environmental issues, and assist educational organisations and networks around the world.

For more information, visit WRI’s Environmental Education site: http://www.wri.org/wri/enved/or contact Kathy Doucette, Environmental Education Assistant at Kathyd@wri.org.

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