This species is recorded from the Diuata Mountains (Brown and Alcala 1977) and Mount Kitanglade in northeast Mindanao, in the Philippines. Current distribution data suggests that it inhabits forest areas on both sides of the Agusan River valley (Beukema 2011). Recent collections of this species at high elevations (ca 1,900 m asl) on Mts. Balatukan and Lumot and on Dinagat Island clarify that, as currently understood, this species is considerably more widespread throughout much of northern and central Mindanao than previously thought (Sanguila et al. 2016). It occurs from 800–1,900 m asl, its extent of occurrence (EOO) is 15,935 km2, which is thought to represent fewer than ten threat-defined locations.
Habitat and Ecology
This species inhabits streams and rivers in lower montane and lowland forests. Individuals have been found during the day, hiding among leaf litter and rocks within the small stream (Beukema 2011). It has not been recorded from any modified habitats. Reproduction presumably takes place by larval development in streams.
It is an uncommon species, and appears to be more uncommon than other Limnonectes species (A. Diesmos pers. comm. March 2018). Two individuals were observed over eight person-hours from ca 10 km north of the boundary of Mt. Kitanglad Range Natural Park during 16–28 April 2010 (Beukema 2011). Due to ongoing decline in the extent and quality of habitat, the population is suspected to be decreasing.
Many of the known localities are within protected areas (Mts. Hilong-Hilong, Kitanglad) or proposed protected areas (e.g. Mt. Lumot), so some subpopulations of this species are likely well protected for the foreseeable future (Sanguila et al. 2016). Threats to this species, outside of protected areas, include deforestation due to agriculture, and the pollution and siltation of streams and rivers from agricultural pesticides, herbicides, and mine tailings. Harvesting for human subsistence is a possible threat.
It has been recorded from several protected areas, including Mts. Hilong-Hilong and Kitanglad, and one proposed protected area, Mt. Lumot.
There remains a need for much improved protection of the remaining rainforest habitats on Mindanao, especially riverine habitats and gallery forests. Conservation measures must include the regulation and proper disposal of pesticides and herbicides.
More information is needed on this species' distribution, population status, ecology, and threats. Human exploitation of this species needs to be investigated to determine if this activity needs to be regulated.
Red List Status
Listed as Vulnerable because its extent of occurrence (EOO) is 15,935 km2, it occurs in fewer than ten threat-defined locations, and there is continuing decline in the extent and quality of its forest habitat on Mindanao Island in the Philippines.
IUCN SSC Amphibian Specialist Group 2018. Limnonectes diuatus. The IUCN Red List of Threatened Species 2018: e.T40799A58476417. http://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T40799A58476417.en .Downloaded on 22 January 2019