Silvofishery benefits people and environment

By M. Khazali and Khotib

JAKARTA (JP): Almost all mangroves along the north coast of Java have been cleared out and converted to shrimp ponds except a few areas in which ponds are managed and owned by local people.

Usually, mangrove forests are damaged in the areas where shrimp ponds belong to outside interests whose owners generally live in cities. These owners usually do not care about the adverse impact on the mangroves because it does not influence them directly. They just want to generate as much money as fast as possible. In such areas, local residents do not want to plant and conserve mangrove trees because they do not benefit from them directly.

Besides, local residents, who are usually fishermen, farmers or unskilled workers, do not have access to the coastal area.

Silvofishery, which utilizes mangrove forests in saltwater aquaculture and which has been existing for a long time in a few areas in Java, is a way to save mangroves.

Originally, silvofishery was established by local people to protect their ponds from erosion. It was then found that their shrimp yields from their ponds increased. It was an accidental discovery.

To make such a system work, first, local people must be given a chance to possess and manage ponds, supported by government policy. Furthermore, they must be encouraged to increase their own knowledge and skills on mangrove functions and their benefits, rehabilitation techniques, aquaculture management and to study techniques at effective silvofishery sites.

Silvofishery can also become a sustainable resource of income for local people. Based on research in 1995, local people who possessed and managed ponds using silvofishery generated larger incomes than those who lived in aquaculture areas belonging to outsiders, or those who worked as fishermen, farmers, or unskilled laborers.

The research indicates that silvofishery can save mangrove forests as well as enhance the welfare of local people living in coastal areas. In short, silvofishery can become an important component in solving the poverty problem in coastal areas.

Essentially there are two silvofishery systems in Java -- government-managed and locally-managed.

In government-managed silvofishery areas, mangrove trees usually cover 80 percent of the area and the other 20 percent consists of ponds for aquaculture. Mangrove trees are planted in the middle of the ponds. The government allows local people in the surrounding areas to raise shrimp or fish as long as they responsibly protect the mangrove trees.

In silvofishery areas managed by local people, there is no definite ratio between mangrove trees and the pond areas. A green belt of between 100 meters and 200 meters is usually developed. Ponds are placed behind the green belt and mangrove trees planted in the ponds. Canals with a width of one or two meters are created for water circulation.

There are two key technical questions related to the silvofishery system managed by local people.

First, the minimum area for a green belt which could potentially save the surrounding environment from erosion and the intrusion by sea fauna habitat must be determined. Second, the ratio between the mangrove area and the pond area that yields the maximum advantage for local people must also be decided.

The second question is very significant, and community involvement is key to the establishment of local strategies in silvofishery. If local people cannot generate a significant income from the fishery, it is difficult to make the silvofishery system work.

Local people should be given opportunities to learn that saving mangroves offer advantages to them so that they will feel encouraged to take measures to conserve mangroves of their own accord.

In addition, studies on the silvofishery system should also be conducted on a scientific basis, with the results disseminated to shrimp pond farmers. Such studies are still very limited at present.

The writers are working for Wetlands International's Indonesian program.