**3.1 Assessing and quantifying threats to current diversity, and determining impacts**

Analyses have previously shown that species richness is negatively related to human population density (A.C. Hughes et al., in prep b), and therefore further increase in human population size is likely to have detrimental effects on bat biodiversity. Projections suggest that human populations will continue to increase until at least 2050 and further urbanisation is likely throughout SEA (CIESEN, 2002; Gaffin et al., 2003; United Nations Population Division, 2008; Seto et al., 2010). Larger human populations impinge on biodiversity in a number of ways: through increased demand for wild-sourced products and via higher pollution (Corlett, 2009; Peh, 2010). Urbanisation and increasing deforestation also increase the potential for invasive species to spread throughout SEA (Riley et al., 2005) and further work is necessary to determine the effects of invasive species on the native fauna.

Forest fragment size correlates positively with bat species richness (Struebig et al., 2008; A.C. Hughes et al., in prep b). As deforestation is projected to increase throughout most of SEA, including in "protected areas" (Fuller et al., 2003), this trend is likely to lead to progressive loss of species richness in many areas due to the increased fragmentation of large forest patches. Currently many protected areas fail to offer protection, and are subject to both high hunting pressure (Steinmetz, et al., 2006) and deforestation (Fuller et al., 2003). Heightened accessibility of parks and involvement of rangers may indeed lead to greater pressures within National Parks than in other forested regions. Many regions were predicted to have high species richness during this study, however many forests have been described as showing "empty forest syndrome" (Redford, 1992; Tungittiplakorn & Dearden 2002). Therefore although many areas may be suitable for certain species, they are overexploited by humans, and do not contain the native fauna previously held. Empty forest syndrome and overexploitation have serious implications for a wide range of species: rodents are the most "harvested" taxa, followed by bats, and almost all bat species in SEA are eaten (Mickleburgh et al., 2009). The loss of species due to hunting has implications for the entire ecosystem. Frugivorous and nectarivorous bats, large bodied mammals and birds all have essential functions in seed dispersal and pollination and fulfil vital ecosystem services, yet such species are often the most threatened by human hunting activities. If such species are lost, there may be negative consequences for the entire ecosystem. Yet these animals are among the most hunted organisms in the region (Wright, et al., 2007; Corlett, 2008; Brodie et al., 2009).

When projections of the distribution of bats under future climatic scenarios are made, three broad outcomes can be noted (Fig. 2) (A.C. Hughes et al., in review). First almost all species are projected to show reductions in original range under future scenarios and second, most species are projected to move north. The third probable outcome is the large projected loss of species (up to 44) from areas currently predicted to have the highest levels of species richness (figs 1-2). Though some species were projected to show expansions in original range, this is unlikely to be logistically possible due to the limited dispersal abilities of many species (Struebig et al., 2008). This loss in species richness is based on climate change alone,

Identification of species present, their ranges and trends in distribution and population form an important first step in the development of effective conservation plans. Once these steps have been fulfilled then threats to current distributions and diversity can be analysed (Fig.

**3.1 Assessing and quantifying threats to current diversity, and determining impacts**  Analyses have previously shown that species richness is negatively related to human population density (A.C. Hughes et al., in prep b), and therefore further increase in human population size is likely to have detrimental effects on bat biodiversity. Projections suggest that human populations will continue to increase until at least 2050 and further urbanisation is likely throughout SEA (CIESEN, 2002; Gaffin et al., 2003; United Nations Population Division, 2008; Seto et al., 2010). Larger human populations impinge on biodiversity in a number of ways: through increased demand for wild-sourced products and via higher pollution (Corlett, 2009; Peh, 2010). Urbanisation and increasing deforestation also increase the potential for invasive species to spread throughout SEA (Riley et al., 2005) and further

work is necessary to determine the effects of invasive species on the native fauna.

Forest fragment size correlates positively with bat species richness (Struebig et al., 2008; A.C. Hughes et al., in prep b). As deforestation is projected to increase throughout most of SEA, including in "protected areas" (Fuller et al., 2003), this trend is likely to lead to progressive loss of species richness in many areas due to the increased fragmentation of large forest patches. Currently many protected areas fail to offer protection, and are subject to both high hunting pressure (Steinmetz, et al., 2006) and deforestation (Fuller et al., 2003). Heightened accessibility of parks and involvement of rangers may indeed lead to greater pressures within National Parks than in other forested regions. Many regions were predicted to have high species richness during this study, however many forests have been described as showing "empty forest syndrome" (Redford, 1992; Tungittiplakorn & Dearden 2002). Therefore although many areas may be suitable for certain species, they are overexploited by humans, and do not contain the native fauna previously held. Empty forest syndrome and overexploitation have serious implications for a wide range of species: rodents are the most "harvested" taxa, followed by bats, and almost all bat species in SEA are eaten (Mickleburgh et al., 2009). The loss of species due to hunting has implications for the entire ecosystem. Frugivorous and nectarivorous bats, large bodied mammals and birds all have essential functions in seed dispersal and pollination and fulfil vital ecosystem services, yet such species are often the most threatened by human hunting activities. If such species are lost, there may be negative consequences for the entire ecosystem. Yet these animals are among the most hunted organisms in the region (Wright, et al., 2007; Corlett, 2008; Brodie et

When projections of the distribution of bats under future climatic scenarios are made, three broad outcomes can be noted (Fig. 2) (A.C. Hughes et al., in review). First almost all species are projected to show reductions in original range under future scenarios and second, most species are projected to move north. The third probable outcome is the large projected loss of species (up to 44) from areas currently predicted to have the highest levels of species richness (figs 1-2). Though some species were projected to show expansions in original range, this is unlikely to be logistically possible due to the limited dispersal abilities of many species (Struebig et al., 2008). This loss in species richness is based on climate change alone,

1) and necessary conservation actions planned.

al., 2009).

and therefore is a conservative projection, and though it is possible to prevent the loss of species due to deforestation in protected areas it is not possible to prevent species loss due to climatic change. Forest is becoming increasingly fragmented even within "protected areas", and mining rates in SEA are the highest in the tropics (Day & Ulrich, 2000). Mining not only destroys important roost sites (Clements et al., 2006), but also degrades areas and increases accessibility to previously remote areas (which in turn facilitates deforestation, McMahon, et al., 2000; Laurance, 2008a). Therefore not only are current suitable habitat and roosts being destroyed, but the distance between suitable areas may actually be increasing for the same reasons. Other factors such as fires are also prevalent through SEA, and fires have increasingly been found to move north in response to climatic change, therefore posing an increasing threat to the biodiversity of SEA (Taylor et al., 1999). Projections of total biodiversity loss currently estimate the extinction of up to 85% of current biodiversity in SEA within this century (Sodhi et al., 2010). However the estimates of undiscovered species show that we may potentially have only discovered around half of the species in many orders (Giam et al., 2010) and only around 40% of bat species (A.C. Hughes et al., in prep a). Groups containing cryptic species are likely to have particularly high numbers of undiscovered species, and this is highlighted in bats by recent genetic work (Francis et al., 2010). Species with smaller distributions are more likely to have specialist requirements (limiting overall distribution), and will be more susceptible to loss of range and therefore have a higher probability of extinction (Kotiaho et al., 2005). Hence many species currently regarded as widespread, and thus of "Least Concern" by the IUCN may comprise a complex of cryptic species each of which will show higher categories of threat. As almost all species analysed here (fig. 2) showed a loss in original habitat in all scenarios, and many of those species may be species complexes it is likely that impacts for many of the species will be worse than estimated during this study (fig. 2). Projections here (Fig. 2) only account for climate change, but cannot consider hunting, fires, mining and the plethora of other threats. Fungal diseases have recently devastated populations of North American bats (Blehert et al., 2009), in addition to South American frogs (Berger et al., 1999). Moreover the spread of pathogens has been associated with temperature change, for example the spread of chytrid fungus is believed to be related to global warming (Pounds et al., 2006; Boyles & Willis, 2010). Therefore the effect of climate change on species is dynamic and complex, as it has both direct and indirect implications for distributions and populations of all species. Furthermore climatic changes have already been shown to cause changes to the distribution of different biomes (Salazar et al., 2007), and hence has profound implications for species within those biomes.

SEA is currently in the midst of a biodiversity crisis which has been described as a 6th mass extinction (Myers, 1988). There are some undeniable implications of the current threats, and others such as the possibility of 'no-analogue' communities (Stralberg et al., 2009) and the effect of invasive species, which are less certain. However native species are likely to attempt to either migrate north spatially, or move to higher altitudes (Malcolm et al., 2006). Continued decreases in the patch sizes of rainforest will decrease species richness, and increasing accessibility for humans will increase the probability of hunting within areas. Increases in human population will negatively affect biodiversity, if current unsustainable practices continue. Not only is the modification of human activities necessary to decrease further species loss, but human intervention is necessary to allow species any opportunity to respond effectively to climatic changes. The methods to mitigate possible threats require detailed evaluation to try to curb species extinctions.

Fig. 2. A-B.

Mapping a Future for Southeast Asian Biodiversity 9

Fig. 1. The current projected species richness for 171 Southeast Asian bat species on a km2 basis. Projections were generated using Maxent, methods are shown in Box 1. Environmental variables used in projections are included in Appendix 1.

Fig. 1. The current projected species richness for 171 Southeast Asian bat species on a km2

basis. Projections were generated using Maxent, methods are shown in Box 1. Environmental variables used in projections are included in Appendix 1.

Fig. 2. A-B.

Mapping a Future for Southeast Asian Biodiversity 11

Predicting species richness by pairing the known distribution of each species with environmental parameters to determine the habitat requirements of each species, (and thus distribution) can help inform and target research and conservation (Box 1). Such models can also aid conservation planning under probable future scenarios, but are targeted to specific questions and can only incorporate some dimensions of ecosystems and must therefore only be interpreted while acknowledging inputs, assumptions and limitations. Models are a powerful tool for predicting the effects of climatic, land-cover and direct anthropogenic change on species richness (if these anthropogenic drivers have been projected). What such models are less good at is incorporating the biotic dimension, the inter-dependence of some species, and temporal interactions such as the flowering of trees and breeding of organisms (L. Hughes, 2000) which can cause resource asynchrony. More complicated ecological interactions and phenomena cannot yet be incorporated in the building of models, but should be included in the interpretation of results; and thus both dimensions of possible ecosystem change can be used to inform and develop appropriate conservation strategies. Figure 2 shows projections of the effects of climatic change under two potential climate change scenarios (the mildest, and the most severe). Extensive regions are projected to lose between five to nineteen species, with some regions projected to lose up to forty-four species. Though some regions, especially in Northern regions are projected to increase in the number of species, this result should be interpreted with caution for a number of reasons. Firstly these projections only include climatic change, and do not reflect changes in landcover, and secondly many species are dispersal limited and therefore will not to show the expansions projected here. Also the Northern areas of the projection, which are predicted to gain species here are liable to lose species which were not included in these projections, (which include predominantly tropical dwelling species). These projections are highly conservative, for they only show climate mediated loss of species, this is only one driver of species loss and thus the loss of species in these scenarios is liable to represent a fraction of

There are at least three issues that must be addressed if biodiversity is to be most effectively conserved throughout SEA: identification of species and their distributions (Section 3), decreasing the impacts of current threats, and creating ways to allow species to respond to climate change (because halting further climate change is considered impossible, Bowen & Ranger, 2009; Vistor et al., 2009). Each issue requires different actions in order to respond

As stated previously, accurate species identification requires thorough systematic surveys, taxonomic and acoustic studies, and where possible genetic research. However the scale of this work requires the use of university researchers, students and park rangers. The use of citizen science for survey and monitoring has been advocated by some researchers (Webb et al., 2010). However citizen science is plagued with potential problems in SEA: not only is hunting exceedingly popular, but in many taxonomic groups' cryptic species and the lack of adequate taxonomic knowledge precludes species surveys by non-specialists. However education, and enthusing of the population could allow some citizen science in distinct and recognisable species. School children in some parts of SEA also must complete science projects whilst at high school, and with little training such projects could contribute to this

that when all factors are considered.

**4. Mitigating species loss** 

effectively.

Fig. 2. C-D. These maps display the projected change in the number of bat species under the A2 and B1 climate change scenarios produced by the IPPC. A2 represents the most severe of the climate change scenarios and B1 the mildest. Many regions are projected to lose between five to nineteen species, with some regions projected to lose up to forty-four species.

Fig. 2. C-D. These maps display the projected change in the number of bat species under the A2 and B1 climate change scenarios produced by the IPPC. A2 represents the most severe of the climate change scenarios and B1 the mildest. Many regions are projected to lose between

five to nineteen species, with some regions projected to lose up to forty-four species.

Predicting species richness by pairing the known distribution of each species with environmental parameters to determine the habitat requirements of each species, (and thus distribution) can help inform and target research and conservation (Box 1). Such models can also aid conservation planning under probable future scenarios, but are targeted to specific questions and can only incorporate some dimensions of ecosystems and must therefore only be interpreted while acknowledging inputs, assumptions and limitations. Models are a powerful tool for predicting the effects of climatic, land-cover and direct anthropogenic change on species richness (if these anthropogenic drivers have been projected). What such models are less good at is incorporating the biotic dimension, the inter-dependence of some species, and temporal interactions such as the flowering of trees and breeding of organisms (L. Hughes, 2000) which can cause resource asynchrony. More complicated ecological interactions and phenomena cannot yet be incorporated in the building of models, but should be included in the interpretation of results; and thus both dimensions of possible ecosystem change can be used to inform and develop appropriate conservation strategies.

Figure 2 shows projections of the effects of climatic change under two potential climate change scenarios (the mildest, and the most severe). Extensive regions are projected to lose between five to nineteen species, with some regions projected to lose up to forty-four species. Though some regions, especially in Northern regions are projected to increase in the number of species, this result should be interpreted with caution for a number of reasons. Firstly these projections only include climatic change, and do not reflect changes in landcover, and secondly many species are dispersal limited and therefore will not to show the expansions projected here. Also the Northern areas of the projection, which are predicted to gain species here are liable to lose species which were not included in these projections, (which include predominantly tropical dwelling species). These projections are highly conservative, for they only show climate mediated loss of species, this is only one driver of species loss and thus the loss of species in these scenarios is liable to represent a fraction of that when all factors are considered.
