ABSTRACT
Osyczka et al. (2012) reported that timber supply meant for a Polish Antarctic expedition team was contaminated with several species of fungi and insects. Although the survival and establishment of these organisms in the harsh Antarctic conditions are unlikely, it is a glaring example of how human activities can unintentionally result in the introduction of alien species that can lead to problems associated with biological invasion. Under optimum conditions, such introduced species develop traits that enable them to outcompete and dominate in the recipient environment, thus becoming invasive species. Once they become invasive, they alter the ecosystem, threaten the existence of native species, reduce biodiversity, cause economic losses, and degrade the environment. This phenomenon is ubiquitous (Allan et al. 2010) and has been widely described as biological invasion; it is blamed for species extinctions, loss of habitat (Kimbro et al. 2009), and loss of biodiversity (Pimentel et al 2005) and may result in human health hazards (Allan et al. 2010). Invasive species include plants, insects, arthropods, mollusks, fishes, reptiles and amphibians, birds and mammals, and pathogens.
