Philippine warty pig, an ecological engineer
WILD boars, or “baboy damo” in Filipino, are hunted to the brink of extinction in many parts of the country. But did you know that they perform important ecosystem functions that warrant their protection and conservation?
Fortunately, at least one species continues to thrive on Mount Apo—the Philippine warty pig, one of the four endemic wild pigs that are hunted in the country for their meat.
While wild animals are threatened with extinction, even in the unprotected portions of Mount Apo, or areas outside the Mount Apo Natural Park (MANP), a protected area under the National Integrated Protected Areas System (Nipas) Act, a number of unique species continue to thrive, thanks to the strong protection provided by the Indigenous peoples (IPS) living in the area.
Population decline
THE ever-increasing environmental degradation across the country has led to the rapid decline of wild animal populations, including nonvolant, or landbased, mammals and avian species.
Moreover, several species are threatened with extinction due to human persecution and narrowed geographic ranges, authors of a recent peer-reviewed report said.
Some of the largest mammals in Philippine forests, including Philippine brown deer and the Philippine warty pig, are among them.
Also declining in number are some mammals in Mindanao forests, such as the Philippine tree squirrel (Sundasciurus philippinensis), large Mindanao forest rat (Bullimus bagobus), common Philippine forest rat (Rattus everetti), Mindanao treeshrew (Urogale everetti) and palm civet (Paradoxurus hermaphroditus).
Similarly, the population of bird species like the vulnerable giant scops-owl (Otus gurneyi) and Mindanao bleeding-heart (Gallicolumba crinigera) were observed to be declining due to anthropogenic pressures, Jayson Ibanez—one of the authors of the study titled, “Inventory and abundance of nonvolant [land-based] mammals and birds in the unprotected regions of the Mount Apo Range”—told the Businessmirror via Zoom on May 24.
Ecological engineers
THE authors of the study—that included Jhonnel P. Villegas, Jireh R. Rosales and Giovanne G. Tampos—consider wildlife, particularly nonvolant mammals and birds, “ecological engineers” that influence forest vegetation.
Published in the Journal of Threatened Taxa last month, the study that used camera trapping in 2016 and 2020, aimed to conduct a species inventory and assess the relative abundance of nonvolant mammals and birds in the Mount Apo Range.
“Wildlife, such as nonvolant mammals and birds, play a vital role in the maintenance of ecosystem health. They are considered ecological engineers that influence forest vegetation,” the study revealed.
However, due to deforestation, habitat loss and human persecution, wildlife population has declined over the years, highlighting the need to strengthen the protection of Mount Apo’s unprotected regions against destructive human activities, added Villegas, a member of the faculty of Education and Teacher Training at Davao State University.
Villegas explained that the IP communities with ancestral domain rights or claims over vast tracts of lands need all the support— from the national and local governments, and from private institutions—for them to continue protecting the forests and be part of the solution rather than becoming part of the problem.
“While in some parts of Davao City, the IPS are receiving some level of support from the local government, they remain to be wanting,” he said.
Important ecosystem functions
WILD animals play important ecosystem functions.
Mammals regulate prey populations, facilitate seed dispersal and pollination, shape vegetation patterns and act as bioindicators of ecosystem health, the study said.
On the other hand, avian species are important pollinators, scavengers, predators, seed dispersers and ecosystem engineers.
Biodiversity-rich area
THE study highlighted the fact that Mount Apo, which hosts at least three pairs of the critically-endangered species, maintains a highly diverse species of plants and animals despite the many anthropogenic threats (or environmental change caused or influenced by people) that pushes these already endangered animal species to the brink of extinction.
Mount Apo is at the heart of the Mount Apo Natural Park (MANP), an Asean Heritage Park (AHP), the Philippines’ eighth AHP, which means it is among the best of the best-protected areas in the Asean, said Asean Centre for Biodiversity (ACB) Executive Director Theresa Mundita S. Lim.
“[MANP] is one of the first protected established as an [AHP] back in 1984, primarily for being a known habitat of the endemic Philippine eagle,” Lim said.
She pointed out that other than the Philippine eagle, MANP is also a type locality, an area where species are first discovered from, for other unique species, such as the Mount Apo lorikeet, some Mindanao endemic mammals, such as the Mindanao forest mouse, the Philippine tree squirrel and the Apo myna that inhabit the forest Park.
Sought to comment on the study, Lim, a former director of Biodiversity Management Bureau of the Department of Environment and Natural Resources, explained that the recent study that documents Philippine species found inside the MANP, such as Philippine warty pig (Sus philippensis) and Philippine brown dear, are present as well outside unprotected portion of the Mount Apo Range, demonstrates that wild animal populations know no boundaries in their natural movements.
“It is, therefore, vital that some form of sustainable management be put in place for corridors connecting already fragmented habitat ranges,” she suggested.
“Protected areas, such as the MANP, should not be viewed as isolated ‘islands’ of protection, but as part of an interconnected diversity of ecosystems, including urban ecosystems that require integrated action to sustain the benefits it can provide, not just for the wildlife, but for human communities that depend on it,” she said.
Key biodiversity area
THE study authors pointed out that Mount Apo Range is an important Key Biodiversity Area in the Philippines.
A large portion of Mount Apo is within the 64,000-hectare (ha) MANP, which has been the subject of several biodiversity conservation initiatives.
However, a significant portion of secondary and natural forests of the mountain range are left unprotected and, thus, receive fewer conservation initiatives, which is the focus of the new study.
The authors said the situation calls for intensive forest governance and conservation programs beyond the protected landscapes.
“Fortunately, there are IPS in the area because parts of the unprotected regions of Mount Apo Range overlap with the Obu Manuvu Ancestral Domain that is inhabited mainly by the Obu Manuvu people,” Ibanez said.
For the Obu Manubu, the forest is“pusaka,” where an indigenous practice is held to sanctify biotic and abiotic materials that have value to their community. It prohibits hunting wildlife species in most parts of the forest. Only some parts are allowed for hunting, provided that a ritual is performed before the activity.
Camera trapping
BESIDES conducting a species inventory and assessing the abundance of nonvolant mammals and birds in the area through camera-trapping, the researchers also discovered the anthropogenic threats in the area.
A total of 1,106 camera trap days were carried out in 2016 and another 500 days in 2020.
Based on 260 independent sequences in the surveys, 12 species were identified— eight nonvolant mammals and four birds.
Besides the Philippine warty pig (Sus philippensis), among the identified species are the endangered Philippine brown deer (Rusa Marianna), Philippine long-tailed macaque (Macaca fascicularis philippensis) and the vulnerable Giant Scopsowl (Otus gurneyi). Unidentified rodents were also detected in the camera traps.
Unregulated forest clearing
THE authors deployed the camera traps with the help of IPS who are “converts,” or hunters-turned-forest protectors.
They noted the existence of unregulated forest clearing in some parts of Mount Apo Range.
It was observed in barangays Carmen and Tawan-tawan, where around three hectares of trees and undergrowth forest were shaved.
This was also observed at an even larger area downstream in the Kalatong River, where more than 10 hectares of forest were shaved and converted into a grazing area for cattle.
Almost the same forest cover was lost in Kagawasan, Barangay Tambobong, which is now being occupied by some 100 individuals, who have settled in the area.
Tree farmer
A PHILIPPINE warty pig was caught on camera for the first time, doing what they do best—cultivate the soil by digging to find food, and make holes to create a wallowing area, as if to allow seeds that fall from nearby trees to grow on later on—the perfect natural reforestation process.
Moreover, a single camera trap in the 2016 survey captured videos of at least three animal species that used the same Philippine warty pig wallowing hole as drinking and bathing spots. It was also used as a wallowing hole for other species, such as the Philippine dear and the giant scops owl.
This was the first documentation in the Philippines of other forest vertebrates drinking and bathing from the wallowing pit of warty pig.
According to the authors, wallowing is a very important behavior and provides multiple physiological and welfare benefits to warty pigs, the study explained.
“For the first time, using camera traps, we were able to learn of their behavior in the wild,” Ibanez pointed out.
Nutrient recycling
MORE than just a game for hunters, the warty pigs are also scavengers that feed on animal carcasses in the wild. In removing dead animals, like vultures, warty pigs recycle nutrients that are used by plants.
The Philippine warty pig also help prevent the spread of diseases that could lead to an outbreak that can threaten to wipe out the local animal population in the area, or worse, cause a pandemic threatening the human population.
“They help prevent the spread of diseases,” said Dr. Emilia Lastica Ternura of the University of the Philippines Los Baños College of Veterinary Medicine.
There are incidences of mass die-offs due to suspected African swine fever (ASF) affecting Philippine warty pig populations in some parts of Visayas and Mindanao, particularly in Tagum City, she said.
“This happened in 2019, almost the same time that the ASF started to affect areas along the trading path of imported swine,” Temoura added.
She warned that stronger protection measures must be put in place in the wild, particularly against hunters and even mountaineers who climb Mount Apo and other areas, to protect wild animal populations like the so-called ecological engineers from being wiped out by zoonotic diseases, such as the dreaded ASF.
Otherwise, she said there’s a chance that the Philippine warty pig and other wild pig species in the country may eventually become instinct.