Introduction of invasive alien species dramatically alters ecosystems in many parts of the world, especially in the forest ecosystems. In a report submitted by Pinol et al (2006) to the Asia-Pacific Invasive Species Network, he enumerated a list of potential invasive alien species (plants, insect pest and other pathogens) in the Philippines (Table 3). These species can eradicate other species, are prone to pests and diseases. Some species may cause stunted growth, and the pathogens can cause shoot swelling or death to other species.

In a recent conference on the impact of invasive alien species on terrestrial ecosystems, a multidisciplinary group of stakeholders recommended strategies and actions to address this threat, among them: 1) research on disturbance ecology (social, environmental and economic); 2) protection of the natural habitat; 3) restoration of disturbed habitats; and, 4) information and education. They further noted that anthropogenically disturbed habitats provide dispersal sites for invasive alien species. Intact forests, however, are less vulnerable to invasion and should therefore be protected.

• Forest (habitat) fragmentation
• Anthropogenic pressures
• Introduction of invasive alien species
• Other emerging issues
• Conflicting and overlapping roles and mandates