An alien intruder with venomous spikes and a voracious appetite is invading Caribbean waters, devouring native species, menacing beach users and threatening to upset the region’s ecosystem.

The rampage of the red lionfish - a native of the Indian and Pacific oceans - began on August 17 1992, when Hurricane Andrew destroyed a private aquarium and allowed a handful of the predators to escape.

Sixteen years later, the pest presents “the most devastating marine invasion in history”, according to the marine ecologist Mark Hixon, of Oregon State University, who said lionfish were comparable to a plague of locusts.

Infamous for its insatiable appetite - researchers report a single lionfish eating 20 smaller fish in half an hour - the 18in menace is also feared for a sting described by Bruce Purdy, a dive operator, as “so painful, it made me want to cut my own hand off”.

The plague is currently centred on the Bahamas, where a tenfold population increase has been reported this year, but marine experts warn that beach users elsewhere in the Caribbean will be at risk as the venomous species heads south and east. Containing the invasion is crucial for the protection of coral reefs, warns the marine biologist Andy Dehart.

As lionfish spread, they eat the grazing species that keep seaweed from overwhelming reefs already battered by climate change, pollution and other environmental pressures.

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