The periodic climatic warming phenomenon known as El Niño can induce severe and extended dry conditions in Southeast Asia and other areas. The combination of El Niño-mediated drought conditions and poor land use practices can facilitate the penetration of forest fires deep into tropical forests that were previously thought to be fire resistant (Uhl 1998; Fig. 4.1). Transmigration of humans into forests and an increase in accessibility due to creation of roads can further exacerbate the spread of forest fires (Stolle et al. 2003). Forest fires have always been present in the Southeast Asian landscape, but factors such as rapid human population growth, change in land-use and apparently increasingly

Chapter 4: Beyond deforestation: additional threats to Southeast Asian biodiversity

In this chapter, we review the effects of various threats to Southeast Asian biodiversity that are not directly caused by habitat loss and fragmentation. These processes include wildfires, overexploitation of species from hunting and the pet trade, invasive species, climate change and novel zoonotic diseases, which we discuss in this chapter. Clearly of course, many of these factors are not mutually exclusive to habitat loss, and may be indirectly caused or enhanced by habitat degradation. For example, the creation of trails during logging operations can facilitate hunting by increasing access to the forest interior.

Forest Fires

The periodic climatic warming phenomenon known as El Niño can induce severe and extended dry conditions in Southeast Asia and other areas. The combination of El Niño-mediated drought conditions and poor land use practices can facilitate the penetration of forest fires deep into tropical forests that were previously thought to be fire resistant (Uhl 1998; Fig. 4.1). Transmigration of humans into forests and an increase in accessibility due to creation of roads can further exacerbate the spread of forest fires (Stolle et al. 2003). Forest fires have always been present in the Southeast Asian landscape, but factors such as rapid human population growth, change in land-use and apparently increasingly severe bouts of El Niño are now working in combination to increase the probability and