Inventory Of Important Species
Prescillano M. Zamora, Ph.D.
The Project Site is characterized by a wide variety of ecosystem types which is the main reason for the occurrence of high species diversity in the area. The focus here is mainly on the higher forms of life – flora and fauna – so far recorded from the natural terrestrial ecosystem in the project site.
Field surveys conducted between 1989 and 1991 identified non-vascular and vascular plants, as well as vertebrate and invertebrate life forms. The non-vascular plants include lichens, mosses and hepatics, while vascular plants include whisk ferns, club mosses, ferns, conifers and flowering monocotyledons and dicotyledons. Annexes 1, 2, 3 and 4 number the different species.
The invertebrate life forms consist of flying insects, which are also anthropods. Vertebrate life forms include amphibians (frogs and toads), reptiles (skinks, lizards and snakes), and birds such as raptors, wild chicken, pheasants and quails, doves and pigeons, parrots and parakeets, cuckoos, owls, nightjars and frogmouths, swifts, trogons, kingfishers, bee-eaters and hornbills, barbets and woodpeckers and passerlines.
Mammals include shrews and gymnures, bats, tree shrews, primate, rats and squirrels, and even-toed ungulates such as wild pigs and deer. Annexes 5, 6, 7, 8 and 9 list all the invertebrate life forms.
The lower forms of life such as bacteria, protistas and viruses, fungi, algae, flatworms, roundworms, leeches, many groups of anthropods, land snails and river fish were not covered by the field surveys.
Number of Species
Based on field surveys conducted between 1989 and 1991, a total of 1,143 species of mostly higher flora and fauna have been identified from the project site. Of the number of species presently known, the predominant life forms among the plant groups are the ferns and the so-called fern allies with 202 species, and the flower-bearing forms with 353 species. The preponderant life forms among the animal groups are the birds (123 species).
Considering that the project area is small, the number of known plants and animals (species diversity) in the site represents a significant contribution to the known pool of Philippine and world biodiversities.
Future surveys of the ground and canopy layers to cover other groups of organisms not included in the earlier surveys – like the bacteria, fungi and the numerous invertebrates such as the ubiquitous insects – will significantly increase the present number of biodiversity in the site. Indeed, ecologists and botanists in South American tropical rainforest studies have determined that 40 per cent of the biota live in the upper tropical forest canopy without ever visiting the ground.
According to ecological field surveys, the 10 most important species of plants in the project site include two species of gymnosperms, i.e., Agathis philippinensis (almaciga, Araucariaceae) and Dacrycarpus cumingii (iguem, Podocarpaceae), as well as eight species of angiosperms, i.e., Adinandra (sangnauan, Theaceae); Lithocarpus philippinensis; Lithocarpus apoensis; Lithocarpus mindanaensis; Lithocarpus coopertus (oaks, Fagaceae); Syzygium spp (collectively known as tambis tambis, Myrataceae); Leptospermum flavescens (malasulasi, Myrtaceae); and Litsea spp (Lauraceae). (Figure 6)
Rare, Endemic and Endangered Life Forms
The project site is home to rare and endemic life forms, some of which are considered by ecologists as endangered due to habitat destruction or loss, over-exploitation and pollution.
A rare life form is a taxon of low density occurrence that could be threatened to extinction if the environment worsens in the project site where it occurs. An endemic life form is a taxon found only in a given geographic area; it is presumed to evolve locally. An endangered life form is a taxon that is facing likely extinction within 20 years, or ten generations, whichever is longer (Mace and Lande, 1991).
A rare life form could be endemic or not, be endangered or not, or be both endemic and endangered. An endangered life form could be rare or could be both rare and endemic or not.
Among the species of flora identified form the project site are quite a number of rare, endemic and endangered life forms (Figure 4, 7) including 37 species of lichens, 8 species of mosses, 1 species of whisk fern, 9 species of ferns, 1 species of gymnosperm (a conifer), and 84 species of angiosperms (flower-bearing monocotyledons and dicotyledons). Among the species of fauna identified from the project site are quite a number of rare, endemic and presumably endangered life forms (Figure 4, 8). The list includes 5 species of amphibians, 7 species of reptiles, 29 species of birds and 4 species or mammals.
Rare, Endemic and Endangered Plants
Psilopsid (whisk fern). Tmesipteris lanceolata is the only psilopsid from the project site. While known to occur in widely scattered localities in several major islands in the Philippines, this species is not frequently encountered. This is due in part to its very specialized habitat preference, i.e., only on the trunks of certain species of tree ferns in the midmontane (mossy) forests, about 1,600 meters above sea level.
Pteropsid (ferns). Cyathea christii (Cyatheaceae) is a tree fern. It is known to grow only on Mount Apo and adjacent mountains (up to Mount Kitanglad in Bukidnon province).
Ctenopteris pachycaula (Grammitidaceae), an epiphytic fern, is of local distribution in the forests of Mount Apo and Mount Matutum, at about 2,000 meters.
Botrychium daucifolium is a member of the family Ophioglossaceae. Although reported from widely scattered localities in Luzon, Negros and Mindanao, this terrestrial fern never grows in appreciable number of individuals per population. Moreover, such populations are rarely encountered.
Microsorium phanerophlebium is a member of the family Polypodiaceae. It is epiphytic and restricted to Mount Apo and Davao del Norte. It occurs at altitudes of from 800 to 1,500 meters.
Platycerium grande (Polypodiaceae) is a majestic epiphyte found on tree tops. It is now rare in the wild. It is probably the largest species of staghorn fern in the world, its pendant fronds often reaching over two meters long. It Is depleted due to over-collection and habitat destruction.
Coryphopteris dura (Thelypteridaceae), also a terrestrial fern, is known previously by a few collections from the Mount Apo Range and in New Guinea.
Flowering Plants. Scurrula ferruginea (Loranthaceae) is an epiphyte. Although widespread in the southeastern part of Asia and in the western part of the Malay Archipelago, this species has formerly been reported in Palawan. A specimen (Co 3252) collected from the project site (near Site A, at about 1,365 meters), represents the first sighting of this species in Mindanao.
Nepenthes truncate (Nepenthaceae) is unique in its pitcher-like leaf tip. It is of limited distribution, occurring long the eastern half of Mindanao including Mount Apo, and the provinces of Surigao, Agusan, and Davao.
Mosses (a group of bryophytes). The eight endemic species of mosses growing in the project site are: Dacranoloma perarmatum, Dacranoloma leucophyllum (Dicranaceae), Pseudosymblepharis pervaginata (Pottiaceae), Hypodendron fusco-mucronatum (Hypodendraceae), Macromitrium blumei (Orthotricaceae), Symphysodontella subulata (Pterobryaceae), Pinnatella nana (Neckeraceae), and Trichosteleum brevisetum (Sematophyllaceae). They occur in the mossy forest in the project site.
Pteropsids (ferns). Grammatis torricelliana (Grammitidaceae) is an epiphyte. It is known previously by a single collection from the western base of Mount Apo.
Xiphopteris apoensis (Grammitidaceae) is also an epiphyte. It is known previously by a single collection from the midmontane (mossy) forest of Mount Apo at about 2,000 meters.
Flowering Plants. Gymnopachys pulcherrima (Loranthaceae) is a small tree. It is known previously by a single collection from the project site (Co 3259, Mount Apo site A, at about 1,365 meters).
Decaisnina cumingii (Loranthaceae) is an epiphyte. It is known previously by collections from Mount Apo (Davao side, about 1,800 meters). Additional materials were collected near Site B (Co 3247, about 1,375 meters).
Macrosolen angulatus (Loranthaceae) is an epiphyte. It is known previously from collections from Mount Apo at about 825 meters.
Astronia apoensis (Melastomataceae) is a small tree of local distribution in Mount Apo at about 1,500 meters. A variant of this species (previously known as A mearnsii) occurs in Malindang, also in Mindanao.
Aglaia apoana (Meliaceae) is a small tree of local distribution in Mount Apo at about 900 to 1,400 meters.
Ardisia apoensis (Myrsinaceae) is a small tree of local distribution In Mount Apo at about 1,600 meters.
Ardisia recemoso-panniculata (Myrsinaceae) is a small tree of local distribution In Mount Apo at about 1,600 meters.
Myrsine mindanaensis (Myrsinaceae) is a small tree of local distribution In Mount Apo at about 1,300 meters.
Myrsine apoensis (Myrsinaceae) is a small tree that is confined to Mount Apo along ridges in the mossy forest at about 2,250 meters.
Orchidaceae. A dozen species of orchids are endemic or confined to the midmontane (mossy) forest in the project site, occurring at various elevations (i.e., 1,300 to 2,000 meters). These are Acoridium elmeri, Bulbophyllum gnomoniferum, Bulbophyllum lancifolium, Bulbophyllum longipetiolatum, Calanthe davaoensis, Coelogne elmeri, Dendobrium longilabre, Eria davaoensis, Eria tridens, Liparis linearifolia, and Malxis mindanaensis.
Piperaceae. Four species of the family Piperaceae are confined to the midmontane (mossy) forest in the project site, occurring at about 1,200 to 1,300 meters, namely: Peperomia elmeri, Peperomia rivulorum, Piper davaoensis, and Piper varibracteum.
Polygala venulosa (polygalaceae) is an herb. It is known previously by two collections from the project site (Co 3269, Co 3272 at about 1,375 meters).
Agathis philippinensis (Araucariaceae) is a large and widely distributed gymnospermous tree. It is endangered due to logging.
Mastixia trichomata var clarkeana (Cornaceae) is a small flowering tree that is at present known only from Mount Apo. It is also endangered due to logging
Rare, Endemic and Endangered Animals
Philippine Woodland Frog (Rana magna). An endemic species, the Philippine Woodland Frog is now considered endangered throughout the nation because it is being over-hunted for food and also because it requires unpolluted water for successful breeding, water which is no longer obtainable in many places. It has a relatively long tadpole stage that is vulnerable to changes in the forest environment where it occurs.
Broad-headed Forest Frog (Leptobrachium hasseltil). Endemic to Mindanao, it is a true forest frog and lives on the forest floor where the relative humidity ranges from 90 to 100 per cent. This species is rare and seldom encountered due to its cryptic behavior similar to that of the Horned Forest Frog (Megophyes monticola), another frog that lives on the forest floor.
Mueller’s Toad (Ansonia muelleri) is endemic to Mindanao. It is a highland species which occur in abundance in Marbel River. Like all of the Philippine endemic amphibians, its biology remains unknown.
Some European toads have been found to be important source of poly peptides, possessing an active principle such as the hormone cholecystokinin. Philippine toads may turn out to be just as important when opportunity for study becomes available.
Mindanao Toad (Pelophyrne brenipes). Like Mueller’s Toad, the Mindanao Toad is a rare highland species endemic to Mindanao. Its biology is unknown and therefore its medicinal potentials remain undiscovered.
Mount Narrow-mouthed Frog (Oreophyrne annulata) is rare and has been recorded from Mount Talomo and Mount Apo. It is a midmontane (mossy) forest species and, aside from its collection record, its biology and adaptations remain unknown.
Reptiles (Skinks, Lizards, Snakes)
Cuming’s Eared Skink (Sphenomorphus cumingii) is a rare species of reptile and is the largest in the family Scindidae.
Burrowing Skinks (Brachymeles gracilis). Three species of burrowing skinks of the endemic genus Brachymeles occur in the project site, namely: Common Burrowing Skink, Southern Burrowing Skink (Brachymeles schadenbergii), and Cotabato Worm Skink (Brachymeles pathfinderii). These species are rare, and Mindanao is one of the major habitat areas of diversity of Brachymeles.
Variable Malay Monitor Lizard (Varanus salvator). The Monitor Lizard is an ecologically important species in the forest as it is a major carcass feeder. The Monitor is now considered threatened because it is being unsustainably hunted for food.
Reticulated Python (Python reticulates). It is a major pest to poultry farmers and is thus being killed. It is also being unsustainably hunted for food.
Samar Cobra (Naha samarensis). It is reported to be a major cause of death in Mindanao. Through the technology of captive breeding, crystallized venom from the species is a major source of export of the Philippine Serum Laboratory in Alabang, Muntinlupa, Luzon.
Philippine Eagle (Pithecophaga jefferyi). This is the most important bird species in Mount Apo. It is a protected species and a Philippine endemic. BY legislation, it is the national bird of the country and is the symbol of Filipino wildlife conservation efforts. The Philippine Eagle is so wholly adapted to the tropical rainforest ecosystem that any disruptions of this habitat would mean extinction of this species. Although sighted on Mount Apo, the Philippine eagle has not been seen, nor its nest been found within the development area of the geothermal project site.
Mount Apo Myna (Basilornis miranda). It is considered the second most important species of bird in Mount Apo (Dupont, 1972). A rare starling and found only in Mount Apo (i.e., local endemic), it is a protected species and listed in PAWB’s recommended list of birds not eligible for wildlife trade.
Mindanao Lorikeet (Trichoglossus johnstoniae). Like the Mount Apo Myna, the Mindanao Lorikeet is endemic to Mindanao and is a pretected species. It is included in the CITES list of parrots and parakeets not eligible for wildlife trade.
Rufous Hornbill (Buceros hydrocorax). A true forest bird, the Rufous Hornbill is a Philippine endemic. The reduction of the lowland tropical rainforest has drastically diminished the population of this once common species. The Rufous Hornbill has been recommended as an endangered species along with other rare hornbills in Asia.
Other Important Bird Species
Three other species recorded from Mount Apo are considered ecologically important because they are highland forms. These are the Island Thrush (Turdus poliocephalus), Strong-billed Shrike (Lanius validrostis), and PhilippineBullfinch (Pyrrhula leucogenys). These species are rare and Philippine endemics.
Philippine Brown Deer (Cernus mariannus). Called binau by the natives, the subpopulation of the Philippine Brown Deer in Mount Apo is the smallest among those found in the Philippines. It thrives in the mosses and grasses near the peak of Mount Apo. It is excessively hunted and is threatened with extinction.
Flying Lemur (Cynocephalus volans). After the Philippine Brown Deer, the Flying Lemur is the next most important species of mammal on Mount Apo, biologically and taxonomically. It is the only living member of the Order Dermoptera. This is a highly specialized arboreal mammalian group whose other member is the Malaysian Flying Lemur (Cynocephalus variegates). These two species are true herbivores feeding on buds, new shoots and fruits of forest trees. To thrive as an herbivore on forest canopy constitutes a special adaptation. And to thrive as a nocturnal herbivore high in the forest canopy is a major feat in the evolutionary development of mammals.
Other Important Mammals
The two other ecologically important mammalian species are the Philippine Tree Shrew (Urogali everetii) and the Philippine Gymnure (Podogymnura truei). Both these species are endemic to Mindanao and are seen in Mount Apo and Mount Talomo. They are becoming rare mainly because of extensive forest destruction in Mindanao.
Among the wildlife (plant and animal life) so far known from the project site are examples of species with some significant economic potential. Among the plants are species which yield edible fruits (Figure 9), exhibit medicinal properties (Figure 10), produce quality timber (Figure 11), produce raw materials for various goods or articles of trade (Figure 12), and posses high ornamental qualities (Figure 13).
Several wildlife fauna are economically important as income sources through sustainable eco-tourism: one species of wild pig, one species of deer, three species of pigeons and eight species of doves can be alternative sources of protein, while three endemic species of toads are potential sources of medicine.
The existing ecosystem in the project site harbors wild plants and animal species that can serve as indicators of environmental conditions or changes in the project site. Among these are mosses, lichens, lycopods, ferns, flowering plants, frogs and birds.
Lichens and mosses. These groups are known to be extremely sensitive to air pollution, especially to the relatively high levels of sulphur in the ambient atmosphere.
Lycopods and ferns. Lycopodium cernuum (Lycopodiaceae), Blechum orientale, Blechum egregium (Blechnaceae) and Dipteris conjugata (Dipteridaceae) are indicators of impoverished, highly leached acid soils. Pteridium aquilinum var wightianum and Histiopteris incisa (Dennstaedtiaceae) are pioneer species in frequently burned areas. Gleichenia (several species, Gleicheniaceae) often form thickets like Pteridium in open areas of poor soil nutrient status.
Flowering plants. Mischantus floridulus and Imperata cylindrica (Poaceae) are pioneer weed species in cleared, denuded areas. Species of Macaranga + Mallotus (Euphorbiaceae), Cypholophus moluccanus (Urticaceae), Trema orientalis + Trema cannabina (Ulmaceae) are pioneer softwood species (sometimes referred to as weed trees) in cleared denuded areas. Species of Pilea (Urticaceae) are indicators of soils with low water table (or with high water content). Leptospermum flavescens (Myrtaceae) thrives only at altitudes over 1,700 meters above sea level, thus, its absence would indicate certain environmental changes at said altitudes.
Frogs. Some species of frogs are sensitive while others are resistant to changes, providing us with workable – maximum and minimum potential – indicators of certain environmental changes. For instance, the tadpoles of the Philippine Woodland Frog are very sensitive to silted, low oxygen and high temperature waters. Highly eroded habitats, without tree cover and low water retention ground floor are characteristics of denuded forests.
The presence of some tadpoles of the Philippine Woodland Frog (Rara magna) in a particular stream would signify a viable environment. However, the tadpoles of the Common Tree Frog (Polypedates leucomystax), species of the Narrow-mouthed Frogs (Kalaula) or the Black-bellied Frog (Kalophrynus) are resistant to a certain extent to highly silted, stagnant and low biological oxygen demand (BOD) water that are found in exposed and denuded habitats. These species are excellent bio-indicators of deteriorating habitats. Some of these species of amphibians can be used as indicators of water quality.
Birds. The White Eyes which are represented by species of the genera Zosterops, Hypocryptadius, and Lophozosterops are the most abundant birds in the project site and they can serve as indicators of the upper level of tolerable conditions.
On the other hand, the Blue Fantail (Rhipidura superciliaris) is a territorial and insectivorous species and is sensitive to changing environmental conditions. The Blue Fantail therefore can be used as an indicator of deteriorating conditions in the lower level. In the same manner, species of woodpeckers of the genera Megalaima, Chrysocolaptes, Dryocopus and Picoides are indicators of diminishing diversity of cavity nesters in a given forest area.