This species has been recorded from the northern half of Borneo, including Sabah and Sarawak (Malaysia), Kalimantan (Indonesia), and Brunei Darussalam. It probably occurs more widely than current records suggest, especially in areas between known sites. It has been recorded below 300 m asl.
Habitat and Ecology
This species occurs in flat or hilly rainforests, and forms breeding aggregations around forest rain pools and swampy ground. Spawning sites are on the forest floor (Malkmus et al. 2002). It will not tolerate habitat disturbance (I. Das pers. comm. March 2018).
Although not a rare species, it is seldom encountered because it lives in the canopy layer of forests and only descends to lower vegetation in order to breed (Dehling 2011). This species forms rather large breeding aggregations, suggesting that it is locally abundant. Due to ongoing decline in the extent and quality of habitat, the population is suspected to be decreasing.
The principal threat to the species is rapid clear-cutting of lowland tropical rainforest in forest concession land and for oil palm plantations (Indonesia Red List Assessment Workshop May 2017). In Sarawak, it is only known from protected areas so it is not currently threatened (I. Das pers. comm. March 2018).
This species is known from a number of protected areas in Borneo. In Kalimantan, it occurs in Gunung Tarak Protected Forest (Indonesia Red List Assessment Workshop May 2017). In Sabah, it occurs in Kinabalu and Tawau Hills National Parks, Danum Valley Conservation Area and Sepiluk Orang-Utan Centre (Malaysia Red List Assessment Workshop January 2018). It also occurs in Kubah and Gunung Mulu National Parks in Sarawak and Ulu Temburong National Park in Brunei.
More effective protection of lowland forests in other parts of Borneo is necessary.
Further research on this species' taxonomy, distribution, population size, and trends is recommended.
Red List Status
Near Threatened (NT)
Listed as Least Concern in view of its wide distribution and presumed large population.
Specimens of Rhacophorus dulitensis previously reported from Sumatra are now assigned to R. prominanus (Smith 1924, following Harvey, Pemberton and Smith (2002)).
IUCN SSC Amphibian Specialist Group 2018. Rhacophorus dulitensis. The IUCN Red List of Threatened Species 2018: e.T58990A114925606. http://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T58990A114925606.en .Downloaded on 10 December 2018