When you start diving and your eyes are not yet that well trained to spot specific marine life, lionfish and moray eels are probably the most recognizable and first creatures you find and get excited about. At least that’s how it was for me.

Let’s have a closer look at lionfish. Did you realize that not all them are the same? There are at least 12 different kinds. They are all red, but some are a darker and some a lighter red. They all have white stripes, but some stripes are closer together, further apart, thicker or thinner stripes. Some are bigger some are smaller in size. And they have different looking ‘antenna’ at the top of their head.

Lionfish have 18 venomous spines. With these spines as a perfect defense system, they have very few predators. However, some moray eels, barracudas, sharks and groupers don’t mind preying on lionfish despite their poisonous spines.

Lionfish feed mostly on small fish, invertebrates and mollusks. They are skilled hunters using specialized swim bladder muscles to control their location and alter their center of gravity to better attack prey. This is one of the few fish that can swim upside down. They blow jets of water while approaching prey which serves to confuse them so that the small fish face the lionfish instead of swimming away. The lionfish swallows its prey in one single gulp.

The poisonous spines of a lionfish are dangerous to other fish as well as to humans. Their sting can cause pain, nausea, vomiting, fever, numbness, diarrhea, sweating, respiratory problems. Only very young children, elderly and those who suffer of allergic reactions to the venom should be extremely careful around lionfish.

They live from 5 – 15 years old, in shallow waters down to past 100m and have even been spotted at 300m depth. Their distribution is from the Mediterranean, Caribbean, Red Sea, French Polynesia, Micronesia, Australia, Indonesia, Japan to the Indian Ocean.

Maybe due to overfishing of a predatory species like the grouper, in some areas lionfish have become an invasive species. If not kept under control this could cause ecological problems in the future. With their aggressive behavior they force native species to move to waters where conditions are less favorable. It could lead to a change in the food chain and could negatively impact the reef diversity.

Honduras attempted to train sharks to feed on lionfish to control their invasive populations. In some regions, authorities officially cull lionfish and promote them as edible. In other regions, such as Belize, the Bahamas, and the Grenadines, people make jewelry and other decorative items from their spines, fins, and tails.