FLORISTIC INVENTORY OF THE PROPOSED SITE FOR TARSIER TOURISM CENTER IN VILLA AURORA, BILAR, BOHOL, PHILIPPINES

The study assessed the present vegetation composition of the Proposed Site for the Tarsier Tourism Center (PTTC) at Villa Aurora, Bilar, Bohol and performed a comparative analysis with the existing Tarsier Sanctuary (TS) at Canapnapan, Corella, Bohol. The basis for comparison was the computed importance values, species richness, species dominance, and percent distribution of plants according to self-defined DBH classes. Results showed that both sites had very high species richness and evenness values. Common overstorey and understorey plant species found in both areas were katagpo (Psychotria sp.), sagimsim (Syzygium brevistylum [C. B. Rob]Merr.) and bagauak (Clerodendrum minahassae Teijsm. & Binn.). Apart from sagimsim (Syzygium brevistylum [C.B.Rob.] Merr.), selaginella (Selaginella cuppresina Lin.), and lunas (Lunasia amara Blanco) were also common in the ground vegetation of both areas. Percent distribution of trees according to self-defined DBH classes revealed that PTTC had 87.55% of the total recorded plants with DBH measurements of <10 cm. Our data was found lower by almost 10% from TS. Considerable percentages of trees were also shared in other DBH classes for PTTC. DBH class range of 10-20 cm had 6.88%, while 5.58% was computed for DBH class of >20 cm. Percent distribution of trees on these DBH ranges (especially on DBH class >20 cm) indicated the presence of medium and large trees. The largest DBH measured in the PTTC was 70 cm while in TS was only 22 cm. The proposed 10-ha site in Villa Aurora, Bilar, is suited to be utilized as Tarsier Tourism Center. In case the proposed project is to be pursued, enclosure similar to what has been constructed in Canapnapan, Corella, Bohol, Philippines should also be established to prevent stray animals from predating the captive tarsiers.


INTRODUCTION
The Philippine tarsier or Tarsius syrichta (Linne) has attracted a lot of attention of scientists and collectors because of its interesting physical features and habits.It is often fancied as a crossbreed of a bat and a rat.A specific trait of the elongated tarsal region derived the name of "tarsier" (Embury, 1994).
Its size is no bigger than two fists held together.The Philippine tarsier, with three subspecies: syrichta, fraterculus, and carbonarius, is one of the smallest among the different known species (Hill, 1955).This trait and its rarity status would be the reason this creature is on the CITES endangered list.The status was "lower risk conservation dependent" based on the IUCN 2004, and then became "data deficient" in 2006, and now under the "near-threatened" category since 2008 (Shekelle and Arboleda, 2008).
The Philippine tarsier habitats are primarily located in the secondary lowland rainforest of earlyto mid-succession stage (Neri-Arboleda et al., 2002;Reyes, 2006).In Bohol, it occurs in hilly areas with patches of second-growth forest (PAWB-DENR, 1992;Lagapa, 1993;Villamor, 1995;Reyes, 2006), bushes, bamboos, palms, and some grasses (Karnain, et al., 1997;Reyes, 2006).The short trees, as well as bamboos, are good for the arboreal adaptation by the tarsiers.The dense nature of the undergrowth supports a wide variety of insects and small vertebrates which are vital to the survival of tarsiers.
The close distance between small diameter trees, on the other hand, appears to be a necessary condition which favors the locomotive behavior of tarsiers.
These conditions, thus enabling them to have a firm grasp of the small trunks and branches making this type forest a favorable place to live (Villamor, 1995;Karnain, et al., 1997).Abandoned clearings with signs of new growth of medium-high plants in lands of both low and medium elevations were also used by tarsier (Hoogstraal, 1947).These types of clearing were believed to be the tarsier's feeding sites (Rabor, 1977;Villamor, 1995) until disproved by Neri-Arbodela et al. (2002).
Kata kunci: inventarisasi floristic, Philippine tarsier, Bohol, konservasi primata, wisata.been proposed.To assess the suitability of the proposed site, we compared vegetation composition of the proposed tarsier tourism site (PTTC) at Villa Aurora, Bilar, Bohol, Philippines and the existing tarsier sanctuary at Canapnapan, Corella, Bohol, Philippines (TS).The findings of the study of Reyes (2006), on this aspect, were used as the basis for evaluating the suitability of proposed Tarsier Tourism Area in Villa Aurora, Bilar, apart from the usual species richness and dominance assessment.

Overstorey and Understorey Plants
A total of 112 species of overstorey and understorey plants were identified in the PTTC at Villa Aurora, Bilar.These belonged to 82 genera under 44 families (Figure 1).The recorded plant species and genera in PTTC were roughly twice those in TS.Tables 1 and 2 show the summary lists of with the overstorey and understorey vegetation, its ground cover was more than twice species-rich that the recorded ground vegetation in TS.Table 3 presents the summary list of common plants species  selaginella (Selaginella cuppresina), and lunas (Lunasia amara Blanco).These species were also listed common in TS, as shown in Table 4.

Species Richness and Dominance
The results of species richness and dominance computations (Figure 2) revealed that both sites were species-rich given by Shannon-Weiner diversity index values of 4.26 for PTTC and 3.56 for TS.
According to Fernando et al. (1998) (Gruezo, 1997;Fernando et al., 1998;Reyes, 2000).A very high evenness index was accompanied by a very low dominance index.For both sites, Simpson's dominance index values were computed less than 0.04.This value means that there is only less than 4% chance that two individual plants selected in both sites would belong to the same species.Reyes (2000) reported that the species diversity in the identified six roosting territories of the Philippine tarsier in Barangay Cabacnitan, Bilar ranged from 2.01 (low) to 3.125 (high).

Self-defined DBH Classes
The computation of percent distribution of plants in three different self-defined DBH classes ( Proposed Tarsier Tourism Center (PTTC) is planned at Barangay Villa Aurora in the municipality of Bilar the Philippines.The total area of Tagbilaran, 2013).It is located along the stretch of the prominent winding road of Barangay Villa Aurora, a kilometer away from the "famous Bilar-Loboc Man-made Mahogany Plantation.The area will serve as an extension of the 6-haTarsier Tourism Area established at Upper Bonbon, Loboc, Bohol, the Philippines.Also, for a comparison, the Tarsier Sanctuary and Conservation Site (TS) is situated at Barangay Canapnapan in the municipality of Corella, Bohol, the Philippines.This 134-ha conservation site is managed by the Philippine Tarsier Foundation Incorporated (PTFI) and is open to the public, since the 1990s, for recreation and research.Quadrat sampling was used in the collection of data.Twenty quadrats (=plots) were established preferentially within the 10-ha PTTC in Villa Aurora, Bilar.The 10 x 10 m plots were laid selectively on thickets of small diameter trees and shrubs which could be identified as potential roosting sites of the Philippine tarsier.All plants with a diameter at breast height (DBH) of > 1 cm were recorded.Small nested subplot with a dimension of 1 x 1 m was also established in the middle of each plot to facilitate the identification of the ground vegetation.For comparative analysis, ten plots and subplots were also established at TS in Canapnapan, Corella.The first five plots and subplots were laid in the PTFI tarsier enclosure where visitors are allowed to enter and see the captive tarsiers, and the remaining plots and subplots were laid outside the enclosure, about 30 m away from the PTFI building.Analysis of data was mainly concentrated on the determination of species abundance parameters such as density, frequency, and dominance values of each plant species.These parameters were used in the calculation of importance value (IV) of all encountered plants in the overstorey, understorey, and ground vegetation.The IV is a measure of species abundance in an area.It is the summation of the relative values of density (number of species per unit area), frequency (number of occurrences of species relative to the number of plots established) and dominance (basal area of species relative to the total computed basal areas).For the purpose of comparison of the two sites, species richness, and dominance indices like diversity (Shannon-Wiener diversity index), evenness (Evenness index), and dominance (Simpson's index) were computed based on the importance value.The Shannon-Weiner diversity index assumes that individuals are randomly sampled from an indefinitely large population and also assumes that all species are represented in the sample.Evenness index, on the other hand, is the ratio of observed diversity to maximum diversity, while Simpson's index is the probability of any two individuals drawn at random from an infinitely large community belonging to same species.The density of plants, in percent (%), on each pre-defined diameter class was also calculated to evaluate the suitability of the proposed site for tarsier conservation as the project proponents (wildlife permits from Loboc) claimed its very purpose.The comparison was based on the work ofReyes (2006) who tested the relationship of DBH to the number of tarsiers seen in the wild.DBH classes used in this study were: <10 cm; 10-20 cm; and >20 cm.The calculation of formulas was adopted from Gruezo (1997),Fernando et al. (1998),Reyes (2000& 2006),   and ERDS (2009).
DBH class of >20 cm.Percent distribution of trees on these DBH ranges (especially on DBH class >20 cm) indicated the presence of medium and large trees.The largest DBH measured in PTTC was 70 cm.For TS, only less than 3%, combined, was computed for DBH classes of >10 cm.The largest DBH measured was 22 cm.CONCLUSIONThe proposed 10-ha site in Villa Aurora, Bilar, is suited to be utilized as Tarsier Tourism Center.Apart from the site's inherent diversity in plant species, the current vegetation composition and the presence of medium and large size trees in PTTC suggests its similarity to one of the variants described byReyes (2006) as advance thickets of many small diameter trees, few medium-and large-sized trees and dense undergrowth.However, in case the proposed project will be pursued, enclosure similar to what has been constructed in Canapnapan, Corella should also be established to prevent stray cats and other animals from predating the captive tarsiers.

Figure 2 .
Figure 2. Species richness and dominance index values for the Proposed Tarsier Tourism Center, Villa Aurora, Bilar and Tarsier Sanctuary, Canapnapan, Corella, Bohol, Philippines

Table 1 .
List of common overstorey and understorey plants arranged based on importance values in PTTC, Villa Aurora, Bilar, Bohol, Philippines

Table 2 .
List of common overstorey and understorey plants arranged based on importance values in TS, anapnapan, Corella, Bohol, Philippines

Table 3 .
List of common plants species comprising the ground vegetation arranged based on the number of individuals in PTTC, Villa Aurora, Bilar, Bohol, Philippines.

Table 4 .
List of common plants species composing the ground vegetation arranged based on the number of individuals in TS, Canapnapan, Corella, Bohol, Philippines.