This species has been recorded from many localities on Luzon, Catanduanes, Marinduque, Polillo, Camiguin Norte and Pamoctan Islands, in the northern Philippines. It is widely distributed throughout all islands within the Luzon Pleistocene Aggregate Island Complex (Mcleod et al. 2011). Additional surveys in a variety of habitats surrounding the Subic Bay area will be necessary to confirm its anticipated presence (Devan-Song and Brown 2012). It occurs from 40–1,050 m asl.
Habitat and Ecology
This large bodied, semi-aquatic fanged frog inhabits streams and rivers in lower montane and lowland forests, and is also found in forest edge and agricultural areas near intact natural forests. Low elevation subpopulations, subject to predation by humans and introduced frog species, consistently have a smaller average body size than high-elevation subpopulations inhabiting inaccessible montane areas (R.M. Brown and A.C. Diesmos pers. obs.). It presumably reproduces by larval development.
It is common to very common where its habitat remains intact, although some populations are in decline because of over-exploitation. Generalised surveys are still recording the species within the last five years, however fewer large individuals are being observed (A. Diesmos pers. comm. March 2018).
The major threats to this species include habitat loss, due to expanding agriculture, logging and human settlements, and the pollution of streams and rivers. It is potentially at risk from predation and competition from invasive amphibian species Hoplobatrachus rugulosus and Kaloula pulchra (Diesmos et al. 2006). Harvesting by local people is also a threat. In addition, individuals of this species have tested positive for the chytrid fungus (Diesmos et al. 2012).
The range of this species includes a few protected areas. Since the 2004 assessment, in collaboration with various regional academic institutions, NGO-led awareness campaigns have been taking place to educate the public regarding the need to protect remaining forests on Luzon Island, resulting in positive responses by local communities and improved protection for priority species.
Enforcement of protected area boundaries and appropriate management practices are required to safeguard the remaining habitat, as well as ongoing awareness campaigns to raise public support. Conservation measures must also include the regulation and proper disposal of pesticides and herbicides.
More information is needed on this species' distribution, population status, ecology, and threats. Levels of human exploitation of this species need to be investigated to determine if harvesting from the wild needs to be managed more sustainably.
Red List Status
Near Threatened (NT)
Listed as Near Threatened because this species is likely in significant decline (but probably at a rate of less than 30% over 10 years) because of ongoing widespread habitat loss and degradation through much of its range, and over-harvesting for food, thus making the species close to qualifying for Vulnerable.
IUCN SSC Amphibian Specialist Group 2018. Limnonectes macrocephalus. The IUCN Red List of Threatened Species 2018: e.T58350A58479456. http://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T58350A58479456.en .Downloaded on 22 January 2019