PH040
Lake Naujan


Year of compilation: 2001

Site description
Naujan Lake lies near to the north-east coast of Mindoro, approximately 8 km from Pinagsabangan. It is a large freshwater lake probably of volcanic origin, extending for about 14 km from north to south, and 7 km from east to west. The eastern shore is precipitous, but to the west the land rises gradually and there are large areas of shallow water with an abundant growth of aquatic vegetation. There are several hot springs along the eastern shore and the maximum depth of the lake is 45 m. The surrounding areas are covered in a mixture of forest, scrub and grassland with some orchards and coconut plantations. The MUFRC ( Multiple-use Forest Research Center) Experimental Forest lies to the south of the lake, on very steep and broken topography at 200-1,200m. It is in an old logging concession, which in 1980 was mostly covered by secondary growth of predominantly dipterocarp forest and a few patches of grassland and scrubland. However, no forest could be seen in this area in 1991 when viewed from Ilong Peak on Mt Halcon. The main sources of livelihood of the local people are fishing and farming. The species caught include milkfish, mullet, goby, mudfish, tilapia, carp, freshwater prawns and freshwater snails. Where the marshes permit cultivation, the land has been drained, cleared and planted with rice. Important agricultural crops include citruses, coconuts, rambutans and coffee. A very profitable duck raising industry thrives in the surrounding area.

Key biodiversity
Naujan Lake supports large numbers of ducks and other waterfowl, several of which may occur in internationally important numbers. Resident species include the threatened Philippine Duck, which formerly occurred here in substantial numbers but now appears to have declined. The area surrounding the lake used to have extensive lowland dipterocarp forests, notably the MUFRC Experimental Forest, and significant populations of several of Mindoro's restricted-range endemic species, including all of the lowland specialists characteristic of the Mindoro Endemic Bird Area. However, most if not all of this forest appears to have been cleared or degraded, and these species may be locally extinct.

Non-bird biodiversity: Naujan Lake has a rich fish fauna including several protected species. The Philippine crocodile Crocodylus mindorensis, an endangered species endemic to the Philippines, formerly occurred in the area, but may now be extinct on Mindoro. The estuarine crocodile Crocodylus porosus still occurs in the restricted zone of the National Park.



Pressure/threats to key biodiversity
The lake is open to commercial fishing subject to certain limitations, but the enforcement of these regulations and other park regulations is reported to be poor. The Department of Environment and Natural Resources (DENR) has expressed the desire to establish a crocodile farm and crocodile sanctuary at the lake. The lake is rich in nutrients and supports a major fishery of both demersal and pelagic species. Most of the inhabitants of the region depend on the lake for their livelihood. Because of the increase in the human population in the area, the demand on the lake's natural resources has grown rapidly. Fishing is intensive and there is continuing conflict between preserving the National Park for wildlife and development of the area for commercial and subsistence level activities by the local residents. The privately owned fish corral built at the mouth of the Butas River with Government approval constitutes a major threat. Its massive door is opened during high tide and then closed, blocking the exit of marine species in their migration to the sea to breed. The small population of crocodiles, although protected by law, continues to be persecuted; fishermen catch young crocodiles on fishing lines and large animals are killed in nets.

Conservation responses/actions for key biodiversity
The Bureau of Fisheries and Aquatic Resources has a Limnological Laboratory and Experimental Fish Pond at the lake. The Wild Bird Society of Japan (WBSJ) has funded a training course, a two-year environmental monitoring project and several meetings to aid the preparation of a management plan for the site. Surveys are required in this IBA, both to collect more detailed information on the waterbirds and to investigate the current condition of the forests near Lake Naujan, especially the MUFRC Experimental Forest, and to determine whether they still support populations of any threatened or restricted-range birds.

Protected areas
This IBA overlaps with Naujan Lake National Park (21,655 ha), which was declared by Proc. No. 282 on 27 March 1956 and Proc. 335 on 25 January 1968. It is proposed as a Protected Landscape / Seascape under the NIPAS and a management plan is being prepared with the assistance of PAWB and SEARCA. The area was given Ramsar site status in 1999.

Habitat and land use
Naujan Lake lies near to the north-east coast of Mindoro, approximately 8 km from Pinagsabangan. It is a large freshwater lake probably of volcanic origin, extending for about 14 km from north to south, and 7 km from east to west. The eastern shore is precipitous, but to the west the land rises gradually and there are large areas of shallow water with an abundant growth of aquatic vegetation. There are several hot springs along the eastern shore and the maximum depth of the lake is 45 m. The surrounding areas are covered in a mixture of forest, scrub and grassland with some orchards and coconut plantations. The MUFRC ( Multiple-use Forest Research Center) Experimental Forest lies to the south of the lake, on very steep and broken topography at 200-1,200m. It is in an old logging concession, which in 1980 was mostly covered by secondary growth of predominantly dipterocarp forest and a few patches of grassland and scrubland. However, no forest could be seen in this area in 1991 when viewed from Ilong Peak on Mt Halcon. The main sources of livelihood of the local people are fishing and farming. The species caught include milkfish, mullet, goby, mudfish, tilapia, carp, freshwater prawns and freshwater snails. Where the marshes permit cultivation, the land has been drained, cleared and planted with rice. Important agricultural crops include citruses, coconuts, rambutans and coffee. A very profitable duck raising industry thrives in the surrounding area.


Recommended citation
BirdLife International (2022) Important Bird Areas factsheet: Lake Naujan. Downloaded from http://www.birdlife.org on 29/11/2022.