The Philippine slow loris is classified as Vulnerable by the International Union for Conservation of Nature (IUCN, 2015), appearing on the IUCN Red List of Threatened Species. This change from no population or threat evaluation to being assessed as Vulnerable was just announced in the summer of 2020. It is estimated that their populations have experience more than 30% reduction over three generations (approximately 21-24 years), and continuing suspected decline is expected at the same rate based on ongoing extensive harvest of individuals for the pet trade and extensive habitat loss of more than 15% from burning and conversion of forests to oil palm plantations over the last decade, and more than 30% over the next 25 years.

Although relatively adaptable to anthropogenic habitats, they might be less affected by forest loss than some other primate species, forest loss has been so severe in the region that it is likely to have had negative impacts. The species is collected locally for the pet trade; subsequent uncontrolled release of pets in some areas is also a threat, resulting in hybridization with other slow loris species. Captured wild animals are also used as tourist attractions in some hotels or tourist camps in Borneo. The 2015 forest fires on Borneo have been the worst since 2004, and acres of forest have been burned, leading to a significant decrease in the habitat of this species. Lack of law enforcement further threatens the slow loris species across their range.

The taxonomic saga that preceded the 2020 assessment announcement sheds light on the risks of unintentionally misrepresenting species based on insufficient data. When species are more biologically diverse than science previously assumed, it takes years for conservation efforts to catch up. In that time, the situations in which those previously unrecognized species find themselves are likely to grow more precarious.

Indeed, misunderstanding the taxonomy of slow loris species has proven problematic for their conservation both generally and locally. While researchers wrestle with the raw data, conservationists may occasionally misidentify the individual slow lorises that wind up in their care. Since taxonomy determines what they should be fed, how they should be socialized, and where they should be released if they are eventually rehabilitated, proper care and rehabilitation are dependent on proper species identification.

This issue of taxonomy is doubly important given the sheer number of slow lorises that end up in rescue and rehabilitation centers. The biggest threat to all slow loris species is their value as commodities in the exotic pet trade and for traditional medicines. Slow lorises are illegally trafficked and sold all over the world. Buyers rarely have any concern about what variety of slow loris they are receiving. When rescued from these circumstances, a slow loris is inevitably already in rough shape. Suffering from infection, malnutrition, and blindness, and highly stressed by his ordeal, there is no room for error in getting him what he needs as fast as possible. Therefore, proper rapid identification is essential to his rescuers’ success.

Unfortunately, poached from the wild, a slow loris’s chances of survival are small, and rehabilitation leading to their release is even smaller. Even if they are brought back to optimal health, a single consequence of their ordeal will remain that will permanently prevent their eventual release. When first taken, their captors prepared them for sale by removing their teeth—an incredibly painful procedure typically done without any kind of anesthetic. This prevents them from biting future owners and injecting them with venom, which can prove fatal. However, with this one action, the slow loris, a competent and self-reliant creature, is rendered helpless and dependent for the rest of their life. Without teeth, they cannot eat or cannot defend themselves. Ultimately, they have no hope of ever rejoining the wild.

While life in the wild is certainly preferable to life in captivity, slow lorises who avoid becoming pets are still threatened by human encroachment into their natural habitats. When left to their own devices, slow lorises often prove to be quite adaptable and capable of surviving in suboptimal conditions. In many places where they live, however, forests have been degraded to the point where they significantly and adversely affect their rates of survival—and fragmentation of their ranges inevitably inhibits healthy gene flow between spatial groups. What’s more, such trends put them at even greater risk of being found, captured, and sold into the pet trade.

Some populations of Philippine slow lorises likely live in one of the last and largest stretches of continuous ancient forest left in Southeast Asia. Known as the Heart of Borneo, this vast stretch of forest is less than half of what the island once supported. The majority of forested area is concentrated at the center of the island, however, and only small stretches extend to the coastal regions where Philippine slow lorises tend to live. In the last thirty years alone, illegal logging, the construction of dams and other infrastructure, mining, slash-and-burn agriculture, and many other human activities have drastically depleted Borneo’s wilderness, putting the animals that call it home—including many humans themselves—at great risk.

The Heart of Boreno, for now, remains intact. But these trends have not let up. Compounded with the overarching effects of climate change, the future for the Philippine slow loris’s home appears bleak. Slash-and-burn agriculture has become especially problematic over the years. With its peat forests and swamps, Borneo is highly vulnerable to fire. When a fire ignites in one of these environments, it can smolder invisibly underground for weeks. In the wake of such fires, the scorched soil more easily erodes, preventing the forests from ever recovering. September 2019 saw some of the worst fires on record, many of which had been set intentionally in order to clear the land for palm oil plantations. So long as forests remain at risk, so too does the Philippine slow loris.