Taming the Lionfish

When it comes to aquaculture I think most would agree; when they first got into the hobby they looked at marine fish with awe.  One in particular stands out as a species with a wow factor more so than others: I am of course speaking of the Lionfish (Lionfish Pterois sp.) Today about 8 species of Lionfish Pterois sp are recognized within the family of Scorpaenidae as. The family Scorpaenidae has a total of 23 separate genera.

The biggest attraction with this fish is the fact that it’s known as a “hot” species.  When people in the industry refer to “hot” fish, they are not saying that a particular fish is cool looking or sexy in someway. What they are referring to is the fact that it’s venomous.  Besides the lionfish, there are other species of hot species fish available such as Stingrays, Coral Catfish, Stonefish, and Rabbitfish. Most people who get into keeping venomous fish start out with some species of Lionfish Pterois sp.

Poison vs. Venom

There is often confusion between venom and poison.  This is one of my pet peeves as I’m someone who could be a venom addict.  So what’s the real difference between venom and poison?  Poison by definition is something which must be ingested, inhaled, or topically applied to have an effect.  Venom on the other hand is a toxin which is injected by an animal.

That’s it.  There’s really no more to it than that.

With that understanding you can see that bees, wasps, scorpions, snakes, centipedes, and certain fish are venomous. Lionfish Pterois sp. use their spines in an exclusively defensive manner as they are not used to envenomate prey items they feed on so Lionfish Pterois sp. fall into the “venom” category. Poison frogs and puffer fish of the Tetraodontidae family are poisonous as they must be either handled or eaten in order to absorb their toxin.

Taming the Lion

While Lionfish are venomous, keeping Lionfish Pterois sp. does not mean that every time you clean or interact with your marine aquarium you’ll be putting your life at risk.  That doesn’t mean Lionfish Pterois sp. should be taken lightly though.  While there have been no documented cases of death from a Lionfish Pterois sp. envenomation that I could find, one evenomation (getting injected with the venom) will be enough to remind the aquarist that this fish demands respect.  The envenomation incidents that have been reported in aquaria all stem from careless aquarists not paying attention when performing regular tank maintenance.

Most fish will avoid the invasive arm of someone scrubbing their tank. Looking at a Lionfish Pterois sp. in the tank they appear as a rather lazy fish not doing much and can be seen flitting slowly among the tank mates.  Even in the wild they lurk at the edges of reefs without much activity as they have no known predators that are capable of eating them.  This is all part of their evolutionary design.  They appear slow moving as a way to entice prey items to swim closer to them and then open their mouth to swallow the smaller fish.  They do this with lightning like speed and efficiency.

In the aquarium, Lionfish Pterois sp. however are known to back up seemingly moving away from the offensive appendage and then suddenly ram the arm or hand.

Avoiding Envenomation

To avoid a Lionfish Pterois sp. envenomation it is a simple practice of just being aware of where the fish is when you’re cleaning the tank.  The ultimate safety measure would be to take a piece of plexiglass or eggcrate and put this between you and the fish during cleaning sessions.  This may not be reasonable for some aquarists and to those folks I would recommend watching the fish closely while cleaning.  Another method I have seen is to place the fish into a container of some kind and then cleaning the tank completely then releasing the fish back into the aquarium.  This latter method in my opinion stress’ the fish too much to be practical and I don’t recommend it all.

Tag you’re it!

So you think you’re being careful and the next thing you know you feel a stabbing pain in your hand or arm and realize you’ve been envenomated.  Victims will tell you that best thing to do is to remain calm in order to reduce the amount of venom that is moving through the bloodstream.  This is easier said than done.  Being envenomated is a painful experience I am told that it feels worse than a bee or wasp sting.  The best recommendation for treatment is running hot water over the envenomated area as the venom is thermoliable – which means it is broken up by the hot water.  Get the water to a temperature as hot as you can possibly stand it, and then place the envenomation site beneath the running water. Run the water over the wounded area for about 15-20 minutes.   I would highly recommend going to the hospital if you should be envenomated by a Lionfish Pterois sp. as you may have complications which do not arise right away.

The most common effects of envenomation seem to be severe pain in the injection site that can extend up the arm or limb and localized edema or swelling.  Muscle weakness and shortness of breath have also been experienced in rarer cases.  Even rarer still is blistering of the envenomation site and later possible necrosis of tissue around the envenomation area.  Once again just so we are clear there are no known deaths occurring from an envenomation of a Lionfish Pterois sp. Most people experience the localized edema and severe pain and that’s it.

The bottom line of keeping any venomous species whether it is a snake or fish is to be very aware of the animal when interacting within their habitat.  A little precaution goes a long way when dealing with potentially dangerous animals of any kind.  If you understand the risks and respect the animal as a potential threat you will undoubtedly have many years of happy aquaria keeping.

About the Author:

John is an internationally published author of many captive reptile care articles and former editor of the San Diego Herpetological Society Newsletter. He most recently opened the website Reptileapartment.com to answer questions instantly and share free care articles on the captive care of reptile and insect species.  Most recently he has opened The Reptile Living Room where he interviews expert in the field of herpetoculture.  As well as Herpetoculture House eZine where authors within the industry provide quality information on the reptiles, amphibians, and insects being kept without all the clutter of advertisements.

John’s publications include Reptilia, Reptiles Magagazine & TFH Publications Complete Herp Care Series Uromastyx.

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