Lionfish have become the talk of the dive and reef communities. Lionfish are normally confined to the Indian Ocean and the western Pacific, where they're relatively rare. With colourful but venomous spines, the fish has proved a popular aquarium pet. But at some point in the early 1990s, the fish escaped into the wild; how this happened is a subject of much speculation.Since then, the fish has invaded much of the Caribbean, devouring any small fish in its path. They are not particular about where it lives, colonising both reefs and mangrove lagoons. This means young reef fish that typically shelter in mangrove lagoons before they set up home on coral reefs don't stand a chance.
Voracious predators, scientists are increasingly concerned about the effect they could have. In some experiments, lionfish have led to a 70 per cent reduction in native juvenile fish species.
So they have become the target of many hunting expeditions aimed at thinning the herd, including many "If you can't beat'em, eat 'em" campaigns. But while we humans are likely the cause of this invasion, and we are taking to hunting to curb their effect, perhaps we should leave t to nature to fix the problem.
In the Exuma Cays Land and Sea Park – the oldest, largest and 'best-policed' marine reserve in The Bahamas – researchers found ten times fewer lionfish in parts of the reef where there are lots of groupers. Fishing has been banned in the park for 20 years, so it now boasts a healthy grouper population.
But other experts would say the reason you do not find as many lionfish where groupers are abundant is because they force the lionfish out of their territory, just like they do in the Indo-Pacific. Either way, populations are controlled.
