US Congress recognized the problem and had their own staff compile a report.
This is very good report but it stated that information on harmful
nonindigenous species was scattered, obscure, and highly variable in quality
and scientific rigor. The effects of
many species have never been studied. With poor documentation as the report
stated, the magnitude of the problem has probably been underestimated. So we are doing are part to help improve
the knowledge base of at least the aquatic end of the exotic spectrum.
species like the African honey bee, the fire ant, and more recently the West
Nile virus are a human health risk.
While others like the Melaleuca tree and the zebra mussel threaten
widespread disruption of ecosystems by displacing native plants and animals.