As for the plant, CLIMEX parameter values were adjusted iteratively until Ecoclimatic Indices (EI) generated for the flea-beetle matched the known distribution in South America (See Figure 1). Comparison of predictions for North America based on these parameters (See Figure 1) with knowledge of localities where the flea-beetle effectively controlled the weed suggested that locations with an EI between 0 and 25 may support populations of the beetle, but the effects of climate limit population increase and prevent control of the weed. The potential distribution of the flea-beetle and areas of likely success in controlling alligator weed, i.e. where the EI exceeded 25, were predicted for Asia (See Figure 2), Africa and Europe (See Figure 3), and Australia (See Figure 4).

Comparison of the potential distributions for alligator weed and the flea-beetle indicate that the beetle has a more restricted distribution than the weed, and is likely to be successful in controlling the weed over only part of the potential range of the weed. In Australia the beetle is likely to be successful in controlling infestations of alligator weed if they develop in temperate and subtropical coastal areas, but is unlikely to be effective in the southern cooler temperate areas, in the most northern coastal tropics or in inland river systems where alligator weed poses a threat.

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