Hose’s langur  (Presbytis hosei)

Hunting and deforestation pose critical threats to this species across its range. Indeed, the reputed medicinal value of the ‘bezoar’ stones sometimes formed in the monkey’s guts makes this species a target even for hunters uninterested in its meat (6). Interviews with local hunters indicate that hunting for these bezoar stones was the primary reason for the 50 – 80% decline recorded for the species between 1996 and 2003 in Kayan Mentarang National Park, East Borneo, where the forest has remained in fairly pristine condition (8). In this case, a merchant calling at a nearby village in 1998 had reportedly guaranteed to purchase them, sparking excessive hunting of Hose’s langur in the area, to such an extent that 3 years later this hunting was no longer economically viable (8). As a result of habitat loss and hunting pressure, Miller’s grizzled langur (P. h. canicrus) is thought to be critically endangered, or even extinct. Thus, it is listed as one of the world’s 25 most endangered species, although no quantitative surveys have yet been undertaken. Hose’s grizzled langur (P. h. hosei) is considered by many to be in a worse predicament and even more likely to be extinct, although there is a small chance that it exists in the northern part of the Similajau National Park in central coastal Sarawak. Populations may also exist in Brunei, which has suffered much less hunting and deforestation, but hybridization with Everett’s grizzled langur (P. h. everetti) could be a potential issue in this area (6).

Hose’s langur is fully protected in Sarawak, prohibiting individuals from keeping them as pets, or hunting, capturing, killing, selling, importing or exporting them, with stiff penalties of a fine and two years imprisonment if caught (7). The species appears in a few protected areas, such as Kutai National Park and Kayan Mentarang National Park, but the protection offered is frequently inadequate and laws remain unenforced. Indeed, despite being found in national parks, only an estimated 5% of the Kutai National Park forest has escaped logging, illegal settling, industrial development and fire (6), and active protection of Kayan Mentarang National Park has clearly been lacking, having suffered heavily from hunting pressure (8). In such cases, National Park ‘protection’ alone does not guarantee preservation, and more active protection of wildlife against hunting and habitat destruction is desperately required to prevent the extinction of this species. Sadly, it may already be too late for certain subspecies.