Abstract
The main goal of this study was to evaluate the effectiveness of two biological control agents in reducing population growth and spread of the invasive tree Melaleuca quinquenervia, a subtropical tree native to Australia, and invasive in Florida, Puerto Rico, and the Bahamas. While in Florida two insects Oxyops vitiosa (weevil), and Boreioglycaspis melaleucae (psyllid) have been established as biocontrol agents, in Puerto Rico only psyllids are present, and in the Bahamas no biocontrol agents are present. This study combined demographic data, experiments and mathematical models to investigate the influence of the biocontrol agents on M. quinquenervia's spatial population dynamics. In the field, permanent plots were established and demographic data was collected in populations in the native and exotic ranges. Australian populations are comprised mostly of tall adult trees, while in the exotic ranges populations are comprised mostly of short trees (