MOUNT HAMIGUITAN RANGE WILDLIFE SANCTUARY
Mt. Hamiguitan Range Wildlife Sanctuary is an area of exceptional regional biodiversity and endemism in the Eastern Mindanao Biodiversity Corridor. The mountainous topography is covered by five distinct forest habitats each with its own unique biological community. The property is particularly important for several high profile species of conservation concern, notably the Philippine eagle and Philippine cockatoo. The presence of these species, in addition to several others, has led the area to be classed as an Important Bird Area (IBA) by BirdLife International. The property’s biological importance is not limited to fauna, with multiple floral species of significant conservation importance inhabiting the higher altitudinal forest ecosystems. Amongst these species are plants of the genus Nepenthes which are only found within the Mt. Hamiguitan property.
Mount Hamiguitan Range Wildlife Sanctuary
NATURAL WORLD HERITAGE SITE
2014: Inscribed on the World Heritage List under Natural Criterion x.
STATEMENT OF OUTSTANDING UNIVERSAL VALUE
The UNESCO World Heritage Committee adopted the following Statement of Outstanding Universal Value at the time of inscription:
Brief synthesis: Forming a north-south running mountain ridge along the Pujada Peninsula in the southeastern part of the Eastern Mindanao Biodiversity Corridor, the Mount Hamiguitan Range Wildlife Sanctuary has an elevation range of 75-1,637 m above sea level, and provides critical habitat for a range of plant and animal species. The property showcases terrestrial and aquatic habitats and the species that they host at a series of different elevations are responding to highly dissimilar soil and climate conditions. The Mount Hamiguitan Range Wildlife Sanctuary provides a sanctuary to a host of globally threatened and endemic flora and fauna species, eight of which are found nowhere else except Mount Hamiguitan. These include critically endangered trees, plants and the iconic Philippine eagle and Philippine cockatoo.
Criterion (x): The Mount Hamiguitan Range Wildlife Sanctuary represents a complete, substantially intact and highly diverse mountain ecosystem, in a significant biogeographic region of the Philippines. Its diversity of plants and animals include globally threatened species as well as a large number of endemic species including those species that exist only in the Philippines, only in Mindanao and only in the property. The fragile tropical “bonsai” forest that crowns the Mount Hamiguitan Range Wildlife Sanctuary epitomizes nature’s bid to survive in adverse conditions. As a result of its semi-isolation and its varied habitat types growing in dissimilar soil and climate conditions, its biodiversity has shown a significantly high level of endemicity that has led scientists to believe that there may be more globally unique species waiting to be discovered in the area.
The combination of terrestrial and aquatic ecosystems within the boundaries of the property and the large number of species inhabiting each makes the Mount Hamiguitan Range Wildlife Sanctuary home to a total of 1,380 species with 341 Philippine endemics that include Critically Endangered species such as the iconic Philippine eagle Pithecophaga jefferyi and the Philippine cockatoo Cacatua haematuropygia, as well as the trees Shorea polysperma, Shorea astylosa, and the orchid Paphiopedilum adductum. Its high level of endemicity is well exemplified by the proportion of its amphibian (75% endemic) and reptile (84% endemic) species. The Mount Hamiguitan Range Wildlife Sanctuary exhibits segmentation of terrestrial habitats according to elevation. In the lower elevations the agro-ecosystem and remnants of dipterocarp forests house some 246 plant species including significant numbers of endemics such as the globally threatened dipterocarps of the genus Shorea. The dipterocarp forest ecosystem at 420-920 m a.s.l. is characterized by the presence of large trees and is home to 418 plant and 146 animal species, which include threatened species such as the Mindanao Bleeding-heart dove Gallicolumba crinigera and Philippine warty pig Sus philippensis. At higher elevations the montane forest ecosystem exhibits numerous species of mosses, lichens and epiphytes. This ecosystem type houses 105 animal species representing all the animal groups found in the Mount Hamiguitan Range Wildlife Sanctuary as well as the relatively recently discovered rat species, Hamiguitan hairy-tailed rat Batomys hamiguitan. The fourth ecosystem type is the typical mossy forest ecosystem characterized by thick mosses covering roots and tree trunks; it provides habitat for the Philippine pygmy fruit bat, Haplonycteris fischeri and the threatened Pointed-snouted tree frog Philautus acutirostris. At the topmost (1160-1200m a.s.l.) is the mossy-pygmy forest ecosystem, adding a unique natural tropical bonsai forest layer to the property. It is the only known habitat in the world of the pitcher plant Nepenthes hamiguitanensis and the Delias butterfly Delias magsadana.
Integrity: The property is substantially intact and of adequate size to provide for the conservation of its biodiversity and other natural resources. It remains well preserved and intact as evidenced by the results of studies and ongoing monitoring. The Mount Hamiguitan Range Wildlife Sanctuary protects typical mountain ecosystems of the biogeographic region and includes the agro-ecosystem, dipterocarp, montane, mossy, and mossy-pygmy forests. These ecosystems harbour an assemblage of endemic, rare and economically important flora and fauna. The level of vegetative cover indicates that the property is in relatively pristine condition with its surface area covered by a mix of closed and open canopy forest and smaller areas of brush land. The terrestrial and aquatic habitats are well preserved and a number of globally threatened and endemic species rely on or occur within the Mount Hamiguitan Range Wildlife Sanctuary. The Mount Hamiguitan Range Wildlife Sanctuary’s marked vertical zonation of vegetation and associated habitats makes it particularly vulnerable to climate change impact.
Protection and management requirements
The property straddles two municipalities and one city: San Isidro Municipality, Governor Generoso Municipality and the City of Mati, in the Province of Davao Oriental, and totals an area of 16,923 ha with a buffer zone of 9,729 ha. The Mount Hamiguitan Range Wildlife Sanctuary is protected through several protected area regulations and is a component of the Philippines’ National Integrated Protected Areas System (NIPAS). Several layers of national and provincial legislation and policies serve to protect the property and guide management. Apart from delineating the boundaries of the property, these laws prohibit incompatible activities such as logging, mining, exploration or surveying for energy resources inside the property. Responsibility for enforcement is shared by both the national and local government agencies in partnership with other stakeholders. The protection of the Mount Hamiguitan Range Wildlife Sanctuary is further strengthened by the engagement with and involvement of local and indigenous communities living in its periphery in the management of the property. Their lifestyles and spiritual beliefs are based on respect for the environment and its biodiversity and they have, over time, subtly moulded their way of life to ensure the sustainable use of their resources. At the same time, the harsh conditions of the mountain range serve as a deterrent for other human settlements that do not conform to a similarly symbiotic lifestyle. Threats in and around the property include illegal collection of wildlife, mining, development pressures, potential pressures and impacts from tourism and climate change. Management authorities have implemented a monitoring and research programme to anticipate climate change effects on the biota and try to mitigate consequent impacts. Ongoing monitoring will be needed to predict and respond to such impacts.
The Mount Hamiguitan Protected Area Management Board (PAMB) oversees protection and management of the property according to the approved Mount Hamiguitan Range Wildlife Sanctuary Management Plan of 2011. The Protected Area Superintendents Office (PASO) implements the activities set down in the plan as well as the policies and directives issued by the PAMB. Together with the “Bantay Gubat” personnel from the three municipalities with territorial jurisdiction over the property, the PASO conducts regular monitoring and patrol activities over the property and buffer zones. A five year visitor and tourism management plan is in place to ensure the effective management of use, and should be kept updated. The municipalities overlapping the property have aligned their tourism and development plans to the Management Plan of the Mount Hamiguitan Range Wildlife Sanctuary, helping to ensure that the importance of protection of the property will be given the necessary recognition and consideration and that development will not hamper or detract from the conservation and protection of the biodiversity of the Mount Hamiguitan Range Wildlife Sanctuary.
IUCN MANAGEMENT CATEGORY
The Mt. Hamiguitan Range Wildlife Sanctuary (MHRWS) is located in the south easternmost part of the Philippines on Mindanao Island in the Davao Oriental Province. It is bordered on the south by the Davao Gulf in the Sulawesi Sea and on the east by the Pacific Ocean. The boundaries of MHRWS overlap with the Municipalities of the City of Mati and San Isidro. The geographical coordinates to the nearest second N 06o 43’ 1.81” and E 126o 10’24.35”
DATES AND HISTORY OF ESTABLISHMENT
2001: Mt. Hamiguitan is submitted to Congress as a protected area under the designation of wildlife sanctuary.
2004: Mt. Hamiguitan Range Wildlife Sanctuary is formally declared as a protected area of 6,834 ha.
2007: A review takes place focussing on the boundaries of Mt. Hamiguitan Range Wildlife Sanctuary. The results expedite the extension of the property to 7,132 ha, of which 6,348 ha are core area and 783 ha are buffer zone.
2012: The property is first proposed as a World Heritage.
2014: The property is successfully inscribed on the UNESCO World Heritage List as a natural property under criterion x.
The land on which the MHRWS resides is classed as timberland under the Land Classification map (Nos. 2660 and 2687), and belongs to the State.
The property covers 16,923 ha, with an additional buffer zone of 9,730 ha.
The altitude of the property ranges from 75 – 1,637 metres above sea level, being highest in the east of the property.
The MHRWS is part of the Pujada Peninsula and a product of magmatic and tectonic processes generated by the subduction of the Philippine Sea Plate. This tectonic collision caused the oceanic crust to rise up, thereby creating the mountain range and simultaneously generating the Cretaceous volcanic rocks of the Pujada Peninsula. The soils of MHRWS are rich in nickel, iron and cobalt and are exacerbated by high levels of laterite. The MHRWS contains several important watersheds, namely the Bitaugan, Mabua, Damagooc/Timbo, Tibanban and the Mati Cluster. Whilst the Bitaugan River drains in-to the Davao Gulf, the Salingkomot River runs in to the Pacific Ocean, and the Tibanban is the major source of irrigation for the lowlands of San Isidro. In addition to these major rivers the area has multiple minor creeks; however, these are intermittent and can dry up in the summer months. Within the property, there are also a series of waterfalls, as well as Tinagong Dagat Lake. The periphery of the property and some portions of the buffer zone contain an agro-ecosystem which is dominated by coconut trees. Above this agro-ecosystem the dipterocarp forest, which is dominated by Shorea species, spreads into the montane forest. The forest types continue to change with altitude into mossy forest followed by mossy-pygmy forest.
The property falls under Type IV of the Coronas Climate Classification of the Philippines, meaning it is generally a wet climate. This climate type is characterised by an even distribution of rainfall throughout the year and an absence of any long periods of drought or dry seasons. The average annual temperature is 27.8oC and ranges from 22.4oC in January to 33oC in May. Rainfall data recorded from 1996 to 2001 shows that January has the highest levels of precipitation at 151 mm. The average annual rainfall is slightly lower at 126mm. The area’s relative humidity is relatively constant with an annual average of 98%.
The property contains a total of 957 species of flora belonging to 427 genera and 166 families. Of these the vast majority (723) are angiosperms, whilst only 27 are gymnosperms and 151 are ferns. In addition to these species, there is a small community of mosses (17 species), liverworts (13 species) and lichens (13 species). The level of endemism increases with altitude, and endemism is highest amongst angiosperms (Amoroso & Aspiras, 2011). The property also supports multiple threatened species, especially of the genus Shorea, with two being Critically Endangered (CR): Shorea astylosa and S. polysperma, and three Vulnerable (VU) species: S. contorta, S. guiso and S. negrosensis. Nepenthes spp. within the property account for 58% of all Nepenthes found within the Philippines: three of these species have been identified as being endemic to Mt. Hamiguitan. One of these, N. peltata, has a range limited to between 1,100m a.s.l and 1,635m a.s.l. It grows amongst open canopied and mossy montane trees and is potentially threatened by the changing habitat conditions induced by climate change. This trait of highly localised habitat ranges is found in other species, such as N. hamiguitanensis, the newest identified plant species in the property. The diversity of highly endemic and threatened species found within the property clearly indicates the outstanding universal value of the property. The vegetation within the property can be classified under five distinct habitats (Amoroso & Aspiras, 2011). The first, at the lowest altitude is an agro-ecosystem, which although dominated by Coconut and Banana plantations does contain noteworthy remnant species from the dipterocarp forest, e.g. S. guiso and S. polysperma. Above the agro-ecosystem, the second habitat, the dipterocarp forest rises to approximately 900m a.s.l. and supports 418 plant species, including trees that grow up to 30 m in height. The next distinct habitat is the montane forest, which rises until 1160m a.s.l. and is characterised by an abundance of moss, lichen and epiphyte species. A total of 462 plant species have been recorded in this habitat and trees tend to grow to 25 metres in height. The mossy forest, lies above the montane habitat and rises until 1350 m a.s.l. The mosses form thick mats covering roots and tree trunks and epiphytic species, such as Calamus spp. and Freycinetia spp., grow amongst the trees (Amoroso et al. 2009). This habitat is significantly less species rich with only 246 recorded species, and the arboreal species are noticeably shorter with an average tree height of 11 metres. The last habitat type is noteworthy for its renowned 1,234 ha of natural tropical bonsai forest which is considered unique in the world. This pygmy forest is dominated by tropical trees such as Almaciga Agathis philippinensis (VU) and Cedar Dacrydium elatum (VU), and tree heights are on average 1.4 m high. Despite the altitude and unfavourable soil conditions 338 species of plant have been recorded in this habitat.
In summation the montane forest has the highest number of recorded species (Amoroso & Aspiras, 2011; Amoroso et al. 2009), it also has the highest number of species in all plant groups and the highest arboreal species diversity (Amoroso et al. 2009). Furthermore, the montane forest has the highest abundance of endemic species and the dipterocarp forest heh highest abundance of threatened species.
The Mount Hamiguitan Range Wildlife Sanctuary harbours 423 faunal species, 26 of which are mammals. Of these mammalian species, 11 are volant and are predominantly bats. Amongst the 15 non-volant species are: the globally threatened Philippine warty pig Sus philippensis (VU) and the locally endemic common mindanao shrew Crocidura beatus (LC) (IUCN Red List 2015). There are 108 species of bird recorded within the property, covering 74 genera. Around 30% of these species are endemic to the Philippines whilst 19% are endemic to Mindanao. Of the 108 bird species only nine migratory birds were recorded on the site, and four are threatened, including the Critically Endangered Philippine eagle Pithecophaga jefferyi and Philippine cockatoo Cacatua haematuropygia. The Philippine eagle is a large forest raptor and considered to be one of the most endangered eagles in the world (Lovell et al., 2003). Mindanao functions as a stronghold for the Philippine eagle, and has been an established research area for this species for decades (Lovell et al., 2003). Research would indicate that the lowland dipterocarp forest harbours the highest species richness for avifauna, with high numbers of canopy specialists (Relox, Leano & Camino, 2011). A ground-dwelling species of this forest is the Mindanao bleeding-heart dove Gallicolumba criniger (VU), which is nationally endemic.
A study of the property’s Lepidoptera indicated that MHRWS is a sanctuary to a diverse array of endemic butterfly species. Overall, 142 species of butterfly have been recorded within the property, three of which were newly recorded species and 44 were listed as endemics. Of these endemic butterfly species, four species have only been identified within the property itself: Arhopala eridanus davalma, Taraka Hamada dustinkeani, Paraparu cebuensis hamiguitanensis and the rare Delias magsadana. Odonta species similarly contain a high proportion of endemics (29 species of a total of 31). Continuing this trend, amongst the property’s amphibian species 12 of the 16 recorded species are considered endemics, six of which are also globally Vulnerable. The endemism and diversity of Odonta is higher at lower altitudes, especially the lowland dipterocarp forest (Relox, Leano & Camino, 2010). Amongst the endemic amphibian species are the pointed-snouted tree frog Philautus acutirostris and the Mindanao horned frog Megophrys stejnegeri, both classified as Vulnerable on the IUCN Red List (2015). To summarise, the majority of the faunal species within the property reside in the dipterocarp forest towards the lower altitudes of the site or the montane forest above.
The Mount Hamiguitan Range Wildlife Sanctuary is an area of exceptional regional biodiversity and endemism in the southeastern part of the Eastern Mindanao Biodiversity Corridor. The mountainous topography is covered in five distinct forest habitats each with its own unique community. The property is particularly important for several high profile species of conservation concern, notably the Philippine eagle and Philippine cockatoo. The presence of these species, in addition to several others has led the area to be classed as an Important Bird Area (IBA) by Birdlife International. The property’s biological importance is not limited to fauna, with multiple floral species of significant conservation concern inhabiting the higher altitudinal forest ecosystems. Amongst these species are plants of the genus Nepenthes which are only found within the Mt. Hamiguitan property. With threats of mining and deforestation in the area surrounding the property, MHRWS functions as an essential island of biodiversity, and must be protected as such.
The Davao Gulf area is the first region of the country to come into contact with Europeans, especially Portuguese, which happened as early as the 16th Century. Around 300 years ago, the current Davao Oriental Province was part of Caraga Province. The Province became historically important in 1846 when Don Jose Uyanguren attempted to defeat the area which Datu Bago had ruled; although he failed at first, the Moro chieftain eventually evacuated his people to live in the surrounding areas to Mount Apo. Within a couple of years, Don Jose Uyanguren had organised settlements with a considerable number of inhabitants south of Encomienda de Bislig. Today these settlements form the Municipalities of Baganga, Governor Generoso and Mati. These settlements grew partly because of regional violence amongst chieftains, notably the defeat of Datu Bago by Don Jose in 1849. By the end of the 19th Century the Americans overthrew Spanish rule; however, America’s rule was disrupted by the Second World War. The Japanese occupied the peninsula between 1942 and 1945, and in 1946 Philippine independence was declared.
LOCAL HUMAN POPULATION
There are estimated to be fewer than 100 inhabitants within the core zone of the property and again, fewer than 100 residing within the buffer zone. In total these 184 residents are permitted to live inside the property and its buffer zone because they attained their tenurial instruments or permits prior to the declaration of the property as a protected area. There are approximately 40 households in the property and their farmlots and households remain in the designated area of 186 ha. In regard to the barangays (the smallest administrative unit in the Philippines) surrounding the property, the most populous is La Union (approximately 5,000 residents in 2007) and the least populous is Maputi (<500 residents in 2007). The growth in these communities is not considered a significant threat as there was only a 2% growth in the total population between 2001 and 2007. The broader Municipality of San Isidro is presently composed of 16 barangays, the populations of which are predominantly immigrants from the Visayas Region, indigenous people, Mandaya or Lumads. The region is also the premier copra producing area of the country.
VISITORS AND VISITOR FACILITIES
After the discovery of the pygmy forest in 1993 the annual number of visitors has increased. In 2009, an estimated 2,500 visitors visited the pygmy forest but as visitor management was handled by the local governmental units independently of each other visitor data is lacking. With regard to lodging facilities within the property there is one site-based lodging house located at Sitio Tumalite in Barangay La Union, which is near the MHRWS boundary and can accommodate up to ten people. The other three municipalities have several more accommodation options and contain approximately 300 rooms. It is thought that the total capacity of the eight campsites within the property is around 700 people. To date, the maximum carrying capacity of the property to tourists has not been calculated. The required facilities, especially hygiene facilities are not yet in place to enable significantly higher visitor numbers. In light of this, there is a need to create an ecotourism business and management plan to ensure effective and sustainable visitor management within the property. Although visitor infrastructure may still be minimal, the impetus for visitors to come to the site is strong. There are numerous visitor attractions such as waterfalls, hot springs, trekking trails and beaches.
SCIENTIFIC RESEARCH AND FACILITIES
Various conservation efforts have taken place over the years by academics, researchers and NGOs to strengthen the protection and management effectiveness of the property. Technical information in the form of scientific research and biodiversity assessments has assisted the Mount Hamiguitan Protected Area Management Board (PAMB) in the creation of best practice management strategies. The Central Mindanao University, Bukidnon Resources Management Foundation, and Philippine Eagle Foundation also lead an initiative to train MHRWS stakeholders in biodiversity monitoring and evaluation. The Philippine Eagle Foundation was also responsible for developing the Eastern Mindanao Corridor Biodiversity Assessment and Archiving Project (EMCBAAP). This project aimed to assess and archive threatened biodiversity resources, as well as strengthen capacity development of the local stakeholders. In addition to the Central Mindanao University, the University of the Philippines-Mindanao, the University of Southern Mindanao and Davao Oriental State College of Science also undertake research in the property.
The MHRWS was first nominated for World Heritage inscription in 2012 and considered by the World Heritage Committee at its 37th session in Phnom Penh, Cambodia, in 2013. The Committee’s decision at that time (UNESCO WHC Decision 37COM 8B.12) was to refer the nomination back to the State Party so as to allow it to address a number of issues relating to land claims by indigenous people. In 2014, the Committee decided that satisfactory actions have taken place since the 2013 decision to inscribe the site on the World Heritage List. The property is split into two zones: i) the Strict Protection Zone, where human activity is limited to scientific studies and visitors are under the strict guidance of rangers; and ii) a Buffer Zone, which surrounds the Strict Protection Zone and where restrictions are not so stringent. The Mount Hamiguitan Protected Area Management Board (PAMB) oversees protection and management of the property according to the approved Mount Hamiguitan Range Wildlife Sanctuary Management Plan of 2011. The Protected Area Superintendents Office (PASO) implements the activities set down in the plan as well as the policies and directives issued by the PAMB. Together with the “Bantay Gubat” personnel from the three municipalities with territorial jurisdiction over the property, the PASO conducts regular monitoring and patrol activities over the core and buffer zones. A five year visitor and tourism management plan is in place to ensure the effective management of use, and should be kept updated. Eight forest guards (Bantay Gubat) from three different municipalities have been employed within the protected area to supplement management activities and attain management objectives. Indigenous communities have also been of assistance in the successful management of the property through the application of their knowledge, beliefs and practices. Communication between the local communities and PASO has resulted in one arrest as well as two successful rescue responses to animals. A number of activities are prohibited within the property, including cutting, gathering or collecting of timber or other forest products without a license, squatting, hunting, mineral exploration and also infrastructure construction without a permit. Management of the property will be reviewed every three years using various methods including the Management Effectiveness Tracking Tool (METT).
There are some direct and indirect threats from illegal logging, excessive harvesting of forest products, slash-and-burn farming (kaingin), conversion of the land to agricultural production, as well as mineral explorations in areas adjacent to the property. The illegal felling of trees is rampant in some areas of forest below and outside the MHRWS. This is supposedly occurring because of concerted efforts of the illegal logging financiers and a few local residents who find it a readily available source of income. Although the impact of illegal logging is currently minimal within the property it is still considered a threat for the future as there is an abundance of potentially commercially valuable timber inside the dipterocarp and montane forests. The mining tenements adjoining the MHRWS are of Mati and Governor Generoso Municipalities. Permits were issued to several mining companies by the provincial government in 2013, and although these companies are at various stages of operations, some aimed to start open cut mining methods by 2014. All the mining companies were consolidated by the Asiaticus Management Corporation (AMCOR), which waived 7,000 ha of its mining claim to be a protected habitat for the Philippine eagle. Furthermore, AMCOR collaborated with the Department of Environment and Natural Resources in the delineation of the property’s buffer zone boundaries, meaning AMCOR is fully aware of the property’s presence and legislative protection. AMCOR is set to operate for the next 25 years within the barangays of Macambol and Cabuaya, practically covering the Mati side of Mount Hamiguitan. There is no mining within the San Isidro component of Mt. Hamiguitan.
The Mount Hamiguitan Protected Area Management Board (PAMB) consists of the following six members: Regional Executive Director, Governor and provincial planning officer of Davao Oriental, the Mayors of the three municipalities, Barangay Captains of village centres in the property and tribal chieftains of indigenous peoples. The Protected Area Superintendent’s Office (PASO) is composed of a technical and administrative team, which provide a predominantly managerial role and a team of support staff, who function as wardens, and patrols staff.
The current funding for the ten year MHRWS Management Plan comes from combined sources. At present, the main source is the national government, alongside contributions from the provincial government of Davao Oriental and the three municipalities. Both the Department of Environment and Natural Resources and the Provincial Government of Davao Oriental are responsible for providing (US\$ 112,120), whereas the largest source of funding comes from the Office of the Representative Davao Or. 2nd District (US\$ 224,240). The three smallest sources of funding are the Municipality of San Isidro (US\$ 22, 424) and the Municipalities of Mati and Governor Generoso who both provide US\$ 11, 212. The last major source of funding for the MHRWS is an NGO, the Kalumunan Development Center which provides US\$ 44, 835.
Provincial Government of Davao Oriental: Provincial Governor, Provincial Capital, 8200 Mati City, Davao Oriental.
Department of Environment and Natural Resources: Region XI, Davao City, Director, Regional Executive Direction & PAMB Chairman, Km. 7, Lanang, Davao City.
The principal sources for the above information were the original nomination for World Heritage status, the IUCN evaluation reports and the site’s management plan.
Amoroso, V. B., Obsioma, L. D., Arlalejo, J. B., Aspiras, R. A., Capili, D. P., Polizon, J. J. A, & Sumile, E. B. (2009). Inventory and conservation of endangered, endemic and economically important flora of hamiguitan range, southern Philippines. Blumea: Journal of Plant Taxonomy and Plant Geography, 54, 71–76. doi:10.3767/000651909X474113
Amoroso, V. B., & Aspiras, R. A. (2011). Hamiguitan Range: A sanctuary for native flora. Saudi Journal of Biological Sciences, 18 (1), 7–15. doi:10.1016/j.sjbs.2010.07.003
Bueser, G. L., Bueser, K. G., Afan, D. S., Salvador, D. I., Grier, J. W., Kennedy, R. S., & Miranda Jr., H. C. (2003). Distribution and nesting density of the Philippine Eagle Pithecophaga jeffreyi on Mindanao Island, Philippines: what do we know after 100 years? Ibis, 145, 130–135.
The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 11 February 2015.
Relox, R. E., Leaño, E. P., & Camino, F. A (2011). Herpetofaunal Endemism and Diversity in Tropical Forests of Mt . Hamiguitan in the Philippines, 6 (January 2009), 107–113.
Relox, R. E., Leaño, E. P., & Camino, F. A. (2011). Avifaunal assemblage in Mt. Hamiguitan, Davao oriental, Mindanao Island, Philippines. Journal of Environmental Science and Management, 14 (June), 1–11.