Consider this as biological warfare on the fisheries of the Virgin Islands… [Lionfish] will eat just about every fish that is up to two-thirds their body size. This will leave reefs vulnerable to algal overgrowth and mortality. They are also venomous and a potential threat to anyone that tries to handle them.
Lionfish are not native to the Caribbean and have no known natural predators in the waters of the region. Their voracious consumption of juvenile reef fish already poses a serious threat to fisheries in the Bahamas, where they are multiplying rapidly.
One marine ecologist says that the proliferation of lionfish in the Caribbean “may very well become the most devastating marine invasion in history”. At present, intensive hunt and/or capture efforts seem to be the best bet to prevent the continued southward movement of lionfish down the island chain.
Read more about scientific monitoring of the lionfish invasion here and also here. Also of interest: a brief BBC video about the lionfish problem in the Bahamas.