rhinoceros was discovered in 2007, many methods of eradication and control have been implemented. Although managed by a few introduced infectious pathogens, in some areas the rhinoceros beetle has become permanently established and moved on to banana and sugarcane crops in areas cleared of coconut palms (Hochberg 1991). Palau fell victim to the species in 1942 and on some islands coconut palms were completely eradicated, with overall mortality reaching 50% (Berringer 2007). The coconut rhinoceros beetle has invaded other Micronesian islands before, with devastating results. If this invasive species is not controlled, massive mortalities of both cultivated and wild palms is expected. With an abundance of palm trees and nothing to slow their growth, beetle populations are sure to explode if left unchecked. Guam’s native ecosystems lack the various biological factors (e.g., predation, disease) that control coconut rhinoceros beetle populations in their native range. The threat posed by these invasive beetles cannot be overstated. To prevent this from happening young trees must be protected and dead ones must be cleared in areas of infestation. Coconut rhinoceros beetles favor downed trees as breeding sites, so the mortality of young trees may be the first stage of a developing positive feedback cycle that would be essentially impossible to contain once initiated. In other cases, the tree is left susceptible to secondary infection by pathogens (Hochberg 1991). This boring behavior can be fatal to the tree if the meristematic tissue (i.e., where growth takes place) is jeopardized. Adult beetles chew down into the folded, emerging fronds of coconut palm trees to feed on sap (Ridgell 2011). Discovered in the Tumon Bay area in September of 2007, these organisms are notorious for their ability to decimate coconut palms. Guam’s biodiversity has been under siege for quite some time.Ĭurrently, one of the biggest threats facing Guam’s native ecosystems is the invasion of the coconut rhinoceros beetle ( Oryctes rhinoceros). Several frog species from Central America also have been detected that could pose a threat to crops. Regrettably, the toads didn’t have their desired effect, as they spread to other areas and poisoned native predators with the toxin covering their skin (Fritts and Rodda 1998). Around the same time, Cane toads ( Bufo marinus) were introduced to control sugarcane pests. cargo ship, and have since caused the extinction of 10 of the 13 native bird species. During World War II the brown tree snake ( Boiga irregularis) was unintentionally introduced while aboard a U.S. Guam has a less than pleasant history with introduced organisms. Accordingly, the prevention and management of invasive species is a top priority for many geographically isolated ecosystems, including the Island of Guam. These so-called ‘alien’ and ‘introduced’ species can quickly become invasive if environmental conditions are favorable (e.g., predators absent, nutrients abundant, etc.). Unfortunately, these areas are often ill prepared to combat non-native intruders, which, in many cases, can easily prey upon and out-compete their neighbors. Marine and terrestrial ecosystems of the Indo-West Pacific are among the most biologically diverse regions in the world.
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