Bats of the Wind Cave Nature Reserve, Sarawak, Malaysian Borneo
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Tropical Natural History 11(2): 159-175, October 2011 ©2011 by Chulalongkorn University Bats of the Wind Cave Nature Reserve, Sarawak, Malaysian Borneo MOHD RIDWAN ABD RAHMAN1,2*, ROBERTA CHAYA TAWIE TINGGA1,2, MOHD ISHAM AZHAR2, NOOR HALIZA HASAN3 AND MOHD TAJUDDIN ABDULLAH2 1Centre for Pre-University Studies, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak, MALAYSIA 2Department of Zoology, Faculty of Resource Science and Technology, Universiti Malaysia Sarawak, 94300 Kota Samarahan, Sarawak, MALAYSIA 3Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah, Locked Bag 2073, 88999 Kota Kinabalu, Sabah, MALAYSIA * Corresponding author. E-mail: [email protected] Received: 9 January 2011; Accepted: 20 June 2011 ABSTRACT.– A survey of the chiropteran species at the Wind Cave Nature Reserve (WCNR) in the Bau limestone areas (BLA), Sarawak, was conducted from the 10th to 20th January 2008 and the 10th to 20th April 2009. A total of 297 and 367 (net 646) individuals, representing 14 and 11 (net 17) species from four families were captured in 2008 and 2009, respectively, from an effort of 143 each (net 286) sampling nights. This represents eight new recordings for the WCNR and approximately 85%, 45.9% and 17.7% of the total species recorded in the WCNR, BLA and Borneo, respectively. Over both years the most commonly captured species was by far Penthetor lucasi followed by Hipposiderous cervinus, which were comprised of 63% and 22% of the total (2008 + 2009) captures, respectively. Four and eight species were recorded as the new locality records for Wind Cave (WC) and WCNR, respectively, with Rhinolopus arcuatus*, H. larvatus*, H. coxi*, H. ridleyi, H. galeritus*, Kerivoula pellucida, Tylonycteris robustula and T. pachypus being new records for WCNR and those marked with an asterix (*) being new records for WC. This documentation is of importance for forest conservation and management in future. KEY WORDS: Chiropteran, Limestone, Conservation INTRODUCTION and blood. They are known to roost in foliage, caves, rock crevices, hollow trees, Classified in the order Chiroptera, bats dead bamboo and have adapted to human- can be distinguished from other mammals made structures including buildings (Kunz through their capacity of true flight (Payne and Pierson, 1994; Francis, 2008). Equally, et al., 1985; Koopman, 1994; Kunz and they play a major role in ecosystem Pierson, 1994; Francis, 2008). In terms of services, including seed dispersal and biodiversity, they are the second largest pollination as well as insect regulation order in the class Mammalia after rats and control (Payne et al., 1985; Davidson and squirrels (Rodentia), and are highest in Zubaid, 1992; Mickleburgh et al., 1992; diversity in both the tropical and subtropical Pierson, 1998; Tan et al., 1998). regions (Corbet and Hill, 1992; Jones et al., Caves have been long known to support 2002). large colonies of bats (Meredith and As one of the widely distributed taxa, Wooldridge, 1992). Thus, caves or bats takes up many feeding niches, limestone areas have often been the main including fruits, leaves, flowers, nectar, focus for researchers to assess the diversity pollen, insects, fish, other small vertebrates of bats, especially in Borneo. Among the 160 TROPICAL NATURAL HISTORY. 11(2), OCTOBER 2011 well studied caves are the Niah Cave of cocoa (Theobroma cacao), fruit trees and Niah National Park (NP) (Medway, 1959; poultry farm are the intensive agricultural Harrison, 1966; Lim et al., 1972; Hall et al., activities in Bau districts. 2002; Nyaun et al., 2004; Mohd Ridwan et The annual rainfall is approximately al., 2010) and those of the Bau limestone 4000 mm (Malaysian Meteorological areas (BLA) (Hall et al., 2001; Jub et al., Department, 2008). The district is 2003; Karim et al., 2004; Mohd-Azlan et al., comprised of limestone and is a rich natural 2005; Pathe et al., 2005). Even though there heritage but also is of some economic are quite a number of studies carried out on importance in terms of limestone quarrying, the bat diversity in limestone areas, it is tourism and bird nests (Mohd Azlan et al., believed that there is still a lot of 2005). information to be unveiled due to the unique karst habitat. Field methods, sample identification, The aim of this study was to document processing and preservation.– Field the bats species of Wind Cave Nature sampling was performed using ground Reserve (WCNR) and to compare the netting, harp trapping and hand netting obtained data with the previous studies at (Abdullah et al., 1997; Abdullah, 2003; Hall BLA. et al., 2002). Eight to 12 mist nets and three harp traps were set in various locations MATERIALS AND METHODS supposed to be in the flyways of bats, such as above streams, narrow pathways in the Study Area.– The WCNR (1° 24.915’ N forest, trails, forest edge and the cave and 110° 08.109’ E) is situated in the Bau openings (Faisal et al., 2007; Mohd-Azlan et district of Sarawak. The reserve covers 6.16 al., 2008). The trapping effort was hectares and includes Wind Cave (WC) calculated by the total of the number of nets itself and the surrounding forest (Sarawak and traps used multiplied by the total Forest Department, 1992). It is part of the number of sampling days each trap / net was BLA, which is a narrow belt of limestone used for. covering about 150 km2 in Southwest Bats were identified based on Payne et Sarawak. WC and WCNR are located about al. (1985). Selected morphological 5 km southwest of Bau and 30 km from measurements of the bats were taken using a Kuching. vernier calliper (Mitutoyo), and bats were The WC is situated in a small hill weighted using a Pesola spring balance for surrounded by alluvium, which stands by morphometric studies (Abdullah, 2003). The the riverbank of Sarawak River. It is adult / immature status of each bat was surrounding by a remnant forest of medium determined following Kunz (1988) by sized trees and shrubs, including Excoearia examining the epiphyseal-diaphyseal fusion borneensis (Euphorbiaceae), Popowia on the third, fourth and fifth metacarpals. pisocarpa (Annonaceae), Eugenia sp. The netted bats were marked with labelled (Myrtaceae), Ficus sp. (Moraceae), rings. Female bats were also examined for Palaquium sp. (Sapotaceae) and Firmiana evidence of breeding (carrying pups, malayana (Sterculiaceae) (Khalid, 2008). lactating or pregnant). Captured bats were Surrounding the WCNR, paddy farms held until all the nets were closed (Oryza sativa), rubber (Hevea brasiliensis), MOHD RIDWAN ET AL. — BATS OF THE WIND CAVE, SARAWAK 161 FIGURE 1. A. Rhinolophus arcuatus (Photo by Sigit Wiantoro). B. Hipposideros larvatus (Photo by Faisal Ali Anwarali Khan). C. Hipposideros coxi (Photo by Mohd Isham Azhar). D. Hipposideros ridleyi (Photo by Faisal Ali Anwarali Khan). (maximum duration of 12 hours) to prevent given in the species account (below). The recapture and to reduce stress. liver and muscle were preserved in lysis Selected specimens to serve as museum buffer and 75% (v/v) ethanol. These vouchers were euthanized using chloroform specimens were then deposited at the and subjected to skinning procedure and the Universiti Malaysia Sarawak (UNIMAS) voucher specimen number and details are zoological museum. The species richness 162 TROPICAL NATURAL HISTORY. 11(2), OCTOBER 2011 was calculated by the total number of SPECIES ACCOUNT species caught, and the relative abundance was estimated by the total number of Family Pteropodidae individuals per species divided by the total number of individuals. Cynopterus brachyotis (Müller, 1838) (Lesser short nosed fruit bat) RESULTS New Material.– 2♂ (MZU M/02193, A total of 646 individuals (279 and 367 02195); 1♀ (MZU/M/02194). in 2008 and 2009, respectively) were captured from the 286 trapping nights (143 A total of five individuals were captured trapping nights for both 2008 and 2009), at the forest edges outside the cave vicinity. over the two years, and these represent four Two forms of C. brachyotis have been families and 17 species of bats (Table 1). identified that are distinguished by their This represents 85%, 45.9% and 17.7% of forearm (FA) measurement, where the the chiropteran fauna in the WCNR, BLA larger (Sunda) and smaller (forest) forms and Borneo, respectively. Of the total have a FA > 60mm and FA < 60 mm, samples caught in both years, Penthetor respectively (Campbell et al., 2004, 2006). lucasi was bar far the most abundant species All of the individuals captured belong to the caught in WCNR, followed by Hipposideros larger form. Cynopterus brachyotis is a cervinus, with these two species accounting widely distributed species / species complex for 85% of all captures. Of the remaining 15 and is one of the common fruit bats in species, only four had a relative capture Southeast Asia. It is the tenant of variety of abundance of more than 1% (Table 1). Four habitats, including primary forests (small), species of bats were caught as singletons, disturbed forests, orchards, mangrove namely, H. ridleyi, Eonycteris spelaea, forests and cultivated areas (large) (Payne et Kerivoula pellucida and Tylonycteris al., 1985; Boon and Corlett, 1989; Francis, robustula. Eight species were recorded as 1990; Abdullah, 2003). Cynopterus new locality records for WCNR (Table 2), brachyotis habitually roost in small groups namely, R. arcuatus (Fig. 1A), H. larvatus on trees, particularly under the fronds of (Fig. 1B), H. coxi (Fig. 1C), H. ridleyi (Fig. palms. Their diet is not restricted to fruits, 1D), H. galeritus (Fig. 2A), K. pellucida but they also feed on leaves, nectars and (Fig. 2B), T. robustula (Fig. 2C) and T. some insects as well (Boon and Corlett, pachypus (Fig. 2D), but all species had been 1989; Funakoshi et al., 1993, Tan et al., recorded before in Borneo. In addition four 1998; 1999). According to Mohd-Azlan et species were new locality records for the al. (2010), this species feeds on up to 18 WC itself (Table 3), comprised of R.