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Exotic invasive species are becoming more widespread with the growth of global commerce and the growing need to counter the effects of human-induced environmental degradation and climate change. Many invasive species are unintentionally introduced through commercial shipping practices, while others are intentionally cultivated as ornamental plants or for mitigation of environmental problems. Once transplanted, these plants proliferate quickly and outcompete native species for light, nutrients, water, and space. The risks posed by invasive plants are secondary only to habitat destruction (Chimner et al. 2006). The continued reproductive success of these introduced plants is ensured by a lack of naturally management mechanisms including herbivores or diseases in their new habitat.
Mangrove forests occur naturally throughout most tropical areas of the world but were not native to the volcanic islands of Hawaii. Since their introduction at the turn of the century, however, they have incorporated vast areas and monopolized resources on the barren sandy shores. A severe lack of natural competitors occurs in these areas as they are continuously inundated by salty water, which is toxic to most plants. However, the success of the mangrove is ensured by a number of unique adaptations to these unfavorable conditions. As a result, they have been classified as invasive alien plants on the shores of Hawaii and have had many negative effects on the native flora and fauna of the area (Chimner et al. 2006).

CHARACTERISTICS OF MANGROVES
Most stands of mangrove forest are relatively small, measuring less than 20 hectares. One potential reason for controlled growth of mangrove stands was identified in a 2000 study which found that a high density of propagules within an area leads to increased predation by herbivores. Despite this, red mangrove forests in Hawaii tend to form closed-canopy forest with little or no undergrowth. Mangrove...