Conservation efforts to restrict over-fishing in Wakatobi
Action is being taken on an Indonesian island to tackle over-fishing caused by the increasing use of fish fences – an unsustainable fishing technique.
Monitoring of fishery landings on the island of Kaledupa in the Wakatobi Marine National Park has shown that while fish fences in the area increased from 37 in 2002 to over 200 in 2009, there was an island-wide decline in catch per unit effort by over a half in many areas, combined with a large increase in the proportion of juveniles in the total catch.
The diverse and productive fisheries associated with coral reefs play a vital role in both food security and the economics of many tropical nations. But this important natural resource is under immense pressure from a range of threats, particularly overfishing. This has made a move to sustainable exploitation of reef fisheries a priority for conservation bodies.
In Indonesia, fish fences are one of the most widely used fishing techniques. Positioned on intertidal flats adjacent to coral reefs, they are stationary structures shaped in a funnel design. They are designed to exploit the natural movements of fish stocks into deeper water as the tide recedes, and are highly unselective. This has serious implications for important diurnal and seasonal migrations undertaken by many reef fish species, greatly increasing the potential for local extinctions.
Fish fences are designed to exploit the natural movements of fish stocks into deeper water as the tide recedes and are highly unselectiveThe Wakatobi Marine National Park is Indonesia’s second largest marine protected area, and is also the site for a detailed fisheries management programme implemented by Operation Wallacea and the Darwin Initiative. The intensive monitoring of fishery landings on the island of Kaledupa has provided an insight into the unsustainability of fish fence use.
It has demonstrated a significant increase in effort in the fish fence fishery. The number of fish fences in the area increased from 37 in 2002 to over 200 in 2009, whilst the average size of fences increased by 60%, and mesh size halved.
In the same time period, there was an island-wide decline in catch per unit effort by over a half in many areas, combined with an increase in the proportion of juveniles in the total catch from 4% in 2004, to 29% in 2007.
Tackling the crisis
These patterns are indicative of a fishery in crisis, and have prompted management action to be taken in Kaledupa. This was achieved through the idea of community management, whereby local stakeholders are empowered to participate heavily in the management process, alongside NGOs and government – a process which has been shown to greatly increase compliance and support.
To date, this has culminated in the formation of the Kaledupan Fisheries Forum, which designed a set of bylaws, including a number tailored to address the fish fence fishery. These have since been ratified by local government, and demonstrate the first successful step towards sustainable exploitation of Kaledupan fisheries.