According to reports, the population of the Philippine tarsier (Tarsius syrichta Linne.) declining continuously. This is due to the following reasons: because of conversion of its habitat into settlements and agricultural land, poaching and illegal trade.  Bohol is known as the home of the Philippine tarsier yet  Boholanos are not aware that the  tarsier is  considered as their province’s wealth and   national heritage. This tiny primate can also be seen  in the greater Mindanao Faunal Region that includes the provinces of Bohol, Samar, Leyte, and the huge island of Mindanao.

The status of its population in Bohol is still unknown. Attempts to survey or estimate the status of its population have always been crude at best. In this line, T.D. Reyes, Jr. (CVSCAFT) conducted  habitat characterization of the Philippine tarsier to specifically 1) describe its roosting territories in Corella and Bilar towns of Bohol; 2) identify other population indices like scent marks, faeces, carcasses, food leftover, and small diameter locomotor support; 3) classify and ordinate the data to find relations between tarsier presence, vegetation composition and environmental variables; and 4) give guidelines to protect or restore its  habitat. The research was conducted  from August to October 2006.

Findings

• Four ecosystem types were found common in the Philippine tarsier habitat. These are  grassland, brushland, open forest and closed forest ecosystems. The following are plant communities that were found evident in these ecosystems :
         oChromolaena odorata – Desmodium triflorum community
         o Psychotria paucinerva – Antidesma cordato-stipulaceum var. lancifolium community
         o Ficus variegata var. garciae – Alphinia elegans community
         o Chisocheton cumingianus – Colocasia sp. community
         o Pangium edule – Cephalostachyum mindorense community
         o Artocarpus sericarpus – Cephalostachyum sp. community
• There were also eight main variables identified which explained the differences in these vegetation types. Crown illumination, angular soil blocks and food slopes were strongly correlated to the grassland. Meanwhile, only lower slope differentiated brushland and open forest to the other ecosystems. Mid slope, soil potassium, average height and distance from clearings explained the distinction of closed forest from the other types.
• Results revealed that the Philippine tarsier is observed most frequently in  brushlands and open forests having  abundant small diameter locomotor supports. This is supported by observations that  it prefers  relevès with many small diameter trees than those  with less small diameter trees. The  implication of this is that thickets frequented with small diameter plants in the woody vegetation and open forest of Bohol, have a higher probability of housing a tarsier.  

         The study suggested that ex-situ conservation contributes little to the survival of the Philippine tarsier. It recommended that in-situ conservation is still the best option for  conservation of the said species. Maintaining the Philippine tarsier habitats and territories will help save the primate from extinction.

Source:Philippine Council for Agriculture, Forestry and Natural Resources Research and Development.  Highlights 2007