**2. Threats to biodiversity**

Southeast Asia has been stated by many to be facing a crisis in terms of biodiversity loss (Laurance, 2007). SEA has the highest global rate of deforestation, with rates over double those documented elsewhere (Laurance, 2007). Despite possessing extensive biodiversity, Thailand only has around 17.6% of its potential forest remaining, and Peninsula Malaysia around half (Witmer, 2005). Rates of change in vegetation cover in SEA between 1981 and 2000 were the highest globally (Lepers et al., 2005) and what is more these rates of change are accelerating (Hansen & DeFries, 2004).

Indo-Burma-8th, Philippines-9th) and when the ratio of endemic species relative to area are considered these three are in the top 5 (Phillipines-2nd, Sundaland-3rd, Indo-Burma-5th) (Myers et al., 2000). SEA also contains high endemic evolutionary diversity at species, family and clade levels. On a global ranking Sundaland is in 2nd place, Wallacea 3rd and Indo-Burma 5th in terms of unique evolutionary history, with between 65 - 40 My (million years) of unique evolutionary history in each region (Sechrest, et al., 2002). Therefore SEA contains irreplaceable biodiversity and thus represents a priority area for conservation. Indeed, the forests of SEA have been deemed among the highest of all conservation priorities for

The landscape of SEA is also diverse and varied and comprises a large number of ecoregions (Olson et al., 2001). Stibig (2007) categorised sixteen native forest types, in addition to woodland, savannah, two types of thorn scrub and forest, alpine grassland and cold desert among the native vegetation types. Such diversity in vegetation cover also creates very varied ecosystems with very different animal and plant communities. Karsts (limestone outcrops) make up around 400,000 km2 of SEA, and though they only make up one percent of the land area, around two percent of Malaysian species are endemic to karst landscapes (Clements et al., 2006). Globally karsts also harbour a great proportion of endemic species, and therefore contribute significantly to landscape diversity and heterogeneity throughout

One reason for the high levels of diversity and endemicity in SEA is the dynamic and complex geo-physical history of the region, which has been described as a biogeographic theatre (Woodruff, 2003). Some of the landmasses that form SEA only joined as little as 15 Mya (Million years ago), and the addition of new landmasses caused faults and regional instability in many regions (Hall, 2002), which in turn contributed to the formation of unique biotas. Even at only five Mya SEA had not taken its present shape and landmasses within it were still subject to small but significant movements (Hall, 2002). Since this time glacial cycles have periodically transformed SEA, both in terms of shape and vegetation cover (Woodruff, 2003). During successive glaciations mainland and insular areas of SEA have been joined, and glaciers existed as recently as 10 Kya (thousand years ago) in Borneo and Sumatra (Morley & Flenley, 1987). This dynamic geophysical history has led to a highly complex pattern of species distributions and the area contains no less than three zoo/floro– geographic boundaries: Wallace's line, the Kangar-Pattani line and the Isthmus of Kra (Whitmore, 1981; Baltzer, 2008; Cox & Moore, 2010; A.C.Hughes et al., 2011). Therefore the region has a rich and highly varied biota, and thus represents a priority region for

Southeast Asia has been stated by many to be facing a crisis in terms of biodiversity loss (Laurance, 2007). SEA has the highest global rate of deforestation, with rates over double those documented elsewhere (Laurance, 2007). Despite possessing extensive biodiversity, Thailand only has around 17.6% of its potential forest remaining, and Peninsula Malaysia around half (Witmer, 2005). Rates of change in vegetation cover in SEA between 1981 and 2000 were the highest globally (Lepers et al., 2005) and what is more these rates of change

biologists (Laurance, 2007).

SEA.

conservation.

**2. Threats to biodiversity** 

are accelerating (Hansen & DeFries, 2004).

Loss of habitat and deforestation are not the only threats to the biodiversity of SEA. The Convention on International Trade in Endangered Species (CITES) listed that at least 35 million animals in addition to 18 million pieces of coral (and 2 million kg live coral) were exported from SEA between 1998 and 2007 (Nijman, 2010). Many species are also hunted for recreation (Epstein et al., 2009) in addition to bushmeat (Brodie et al., 2009). Furthermore the Chinese medicine trade is stated to be the "single major threat" for some species (EIA, 2004; Ellis, 2005). These problems are not limited to "unprotected areas" as even National Parks fail to offer protection from either illegal logging (Sodhi et al., 2010) or high levels of hunting (Brodie et al., 2009).

The above mentioned factors affecting biodiversity loss are further complicated by the effects of climate change (Figs.1-2), which may act to amplify other threats, and which itself may be amplified by other threat factors (such as wood burning and subsequent release of greenhouse gases-Brook et al., 2006). Fires present a major threat to biodiversity in the region, and during the past decade major fires have started progressively further north in response to climate change (Taylor et al., 1999). Even without considering of many of these factors, projections of the number of extinctions have been made, which project the extinction of 43% of endemic Indo-Burmese fauna within the next century (Malcolm et al., 2006). Thus despite harbouring considerable biodiversity, few areas in SEA have sufficient levels of protection, and with many new species still to be found (as demonstrated by the rapid rate of discovery (Giam et al., 2010)) it is currently almost impossible to determine the most effective means of conservation prioritisation within SEA given the level of knowledge of much of the fauna, and high levels of corruption (Global Witness, 2007).

Some conservation biologists have advocated the use of "indicator species" to monitor more general threats to biodiversity (Carignan & Villard, 2002). Chosen species must obviously be sensitive to the potential threats in the area, and such species must be possible to monitor in a standardised and repeatable way to generate meaningful and comparable data over large spatial and temporal scales. Indicator species can also be used to indicate trends in overall biodiversity (Mace & Baillie, 2007) and therefore provide a gauge of biodiversity change at large regional scales over time. Bats provide an ideal indicator group (G. Jones et al., 2009), and their diversity means that species can be susceptible to a wide variety of different threats. Bats form a large component of bush-meat through SEA (Mickleburgh et al., 2009), and many of these species often perform vital roles within ecosystems and their loss could have negative implications for a wide range of interacting taxa (Mohd-Azlan et al., 2001). A number of ecosystem services are provided by bat species, including pollination, seed dispersal and insect control, and therefore bats are frequently keystone species (Myers, 1987; Fujita and Tuttle, 1991; Hodgkison et al., 2004). Effective conservation of these keystone species is crucial not only for their survival, but for the ecosystems dependent upon them. Furthermore many bat species are either dependent on forests or caves for foraging and roosting, and some species have limited dispersal ability (Kingston et al., 2003), suggesting that their status may be indicative of destruction and consequent fragmentation of both karst and forest areas.

To try to reduce impacts of the Southeast Asian biodiversity crisis requires a number of steps: quantification of how species are distributed and their distribution changes, analysis of the threats each species faces and determination of the probable impact of threats they are likely to face. Only once these initial steps have been achieved is it possible to formulate

Mapping a Future for Southeast Asian Biodiversity 5

segregation which could denote cryptic species (A.C.Hughes et al., in prep a). Monitoring surveys are also essential to determine distribution and population trends, however funds and specialists are not always available to carry out this valuable work when it requires repeated taxonomic surveys and specialist knowledge. Acoustic analysis and monitoring only requires specialists initially, during the creation of acoustic libraries, and surveys can then be carried out by non-specialists or automated software programs (K.E. Jones et al., 2011). Thus protocols such as these provide a viable means of both identifying species present and subsequently monitoring trends, and may be able to detect variation over shorter periods than in trapping-based monitoring which has been previously been advocated (Meyer et al., 2010). Acoustic surveys are currently limited in species coverage, and are biased towards bat taxa that use high-intensity echolocation calls. Acoustic surveys are therefore best used side-by-side with conventional survey techniques such as using mistnets and harp traps in a standardised manner (MacSwiney G et al., 2008). However invasive trapping techniques are expensive and require highly trained experts, whereas acoustic surveys can be carried out with little training and recordings can then be forwarded to highly trained researchers for analysis, or analysed by software to provide standardised and comparable data for any region. If initially surveys combine both trapping and acoustic techniques to establish acoustic libraries within a given area then those libraries can subsequently be employed to monitor trends in many species across wide areas. The use of common species as indicators for abundance and distribution of rarer species has been found to be accurate in previous studies, as correlations have been found in the trends of common species with other species present (Pearman et al., 2010). Therefore even if acoustic surveys cannot cover all species, the trends in the distributions and populations of common

Logistical constraints also mean that it is not always possible to survey all areas in a region, and thus methods which determine range based on limited spatial knowledge of an organism's total distribution provides a valuable tool when applied properly (i.e. predictive modelling approaches, Box 1, Fig. 1). Former distributions of species and zoogeographic constraints must also be considered and included in analyses of species distributions. Within SEA the geophysical history is to a large extent responsible for the current patterns of diversity and species' distributions, and thus analyses of present species distributions cannot be conducted without by making reference to the past (Woodruff, 2003). The connections and separations of the various parts of SEA during past time periods not only influence current distributions but further constrain possible responses to future change. A zoogeographic transition in the distributions of some animal groups centred around the Isthmus of Kra has persisted for over a million years (De Bruyn et al., 2004). Recent analyses (A.C. Hughes et al., 2011) show that although breaks in the distribution patterns of bats are apparent along the Thai peninsula, they occur not only at the Isthmus of Kra and are influenced by climatic discontinuities in conjunction with biogeographic consequences associated with the narrow breadth of the peninsula; and it is probable that these circumstances have also caused divisions known to occur in the distributions of other taxa in the region (J.B. Hughes, et al., 2003). Zoogeographic transitions have persisted over long time periods along the peninsula because the position of climatic boundaries appears remarkably constant. Climatic discontinuities continue to affect the distributions of species, and will also affect how

species may still be more widely applicable.

effectively species can respond to climatic change in the future.

effective impact mitigation strategies. Though in this chapter bats will provide the main case study (due to their potential as indicator species) most of what will be discussed here is broadly applicable for the conservation of biodiversity throughout SEA, and in developing strategies for mitigating species loss in other regions of the world which faces similar issues to those discussed here.
