Depik (Rasbora tawarensis)Rasbora tawarensis

Conservation Actions

A local fisheries regulation (Qanun Laut Tawar 1999 No.5 Panda Aceh Tengah) prohibits the use of gill nets with mesh sizes smaller than 1.5 cm and fishing closer than 100 m to the lakeshore, but this is not enforced.

No other conservation actions are currently in place.

It is recommended to create and implement a harvest management plan and a recovery plan for this species. Awareness raising within the local community is recommended. This is both with fishers to prevent overharvesting and farmers to lower the use of pesticides and chemical fertilisers.

Location Information

Rasbora tawarensis is endemic to Lake Laut Tawar, Aceh Tengah District, Aceh Province, Sumatra, Indonesia (04°36'N 096°55'E, surface area 70 km²). The lake is an old volcanic caldera with a maximum depth of 80 m, located approximately 1,200 m above sea level (Weber and de Beaufort 1916, Nontji 1991, Kartamihardja et al. 1995).

Sampling in Aceh province by Muchlisin and Siti Azizah (2009) did not reveal the species anywhere else. Another Rasbora species, but not R. tawarensis, was found in tributaries and the outflow of Lake Laut Tawar, Peusangang River (Z.A. Muchlisin pers. obs. 2009).

Geographic Range

Extant

Indonesia

Population Information

The species only occurs in one location (a single lake). It is common, as it is caught in large numbers by targeted fisheries. Interviews with fishermen suggest that numbers are decreasing, based on reduced catch per unit effort estimates.

Threats

Its endemicity to a single lake, and thus its restricted range, makes the taxon intrinsically vulnerable. Rasbora tawarensis is exploited by targeted, unregulated gill net fisheries. The habitat quality is affected by pollution from pesticides and fertilizers used in agriculture, sedimentation caused by deforestation of the watershed, and eutrophication from freshwater aquaculture and domestic waste water. Additionally, invasive species known to modify lake habitats are abundant throughout the lake, especially Oreochromis niloticus and Cyprinus carpio. Clarias gariepinus, an invasive predatory fish, is cultured in ponds around the lake (Z.A. Muchlisin pers. obs. 2009). A decrease in water level has been reported and might be aggravated by the planned construction of a drinking water plant in Takengon, the city located on the lakeshore.

IUCN Red List Account Link

Please click here to see the species' IUCN Red List Account page.