Culling Lionfish-The Unintended Consequences

Culling Lionfish-The Unintended Consequences

Culling Lionfish-The Unintended Consequences

Imagine you’re scuba diving 60’ underwater, feeling good and looking for cool stuff. Up ahead a big green moray eel comes into view which you’d normally be excited about. This time however, there is something wrong with the picture. The eel is approximately 3’ off the reef, swimming very fast, open mouthed and heading straight for you. You start to ascend a little to move out of its way but instead of returning to the reef, the 6’ long, green pile of teeth changes course like a heat seeking missile and follows you straight up into the blue. Its body wraps around your legs and as its head squeezes through your thighs so its bottom jaw rests against your crotch. While it smiles up at you, its teeth suddenly look much bigger and more menacing than ever before…. what happens next?

I know a guy who can tell you exactly what happened next because he was there, unfortunately for him, he was the one tangled up in the eel. Though my buddy would beg to differ, it was actually kinda lucky that the incident happened to him. He was an experienced diver that has worked in the industry for years so was equipped to handle difficult situations underwater, but what if a similar thing happened to someone with only a handful of dives under their belt? He did panic a bit and surfaced faster than he’d normally like while omitting his safety stop, but by the time he got to the surface, the eel had lost interest and swam away.

The whole episode was very strange indeed, as anyone who has spent much time underwater with marine life in its natural habitat will tell you, it’s not normal for something to harass you like that. But that’s just the issue, although this whole thing happened in the open ocean, the eel’s behavior had been influenced by unnatural activity.

To get a better understanding of this, we need to rewind a little, to around 1985. This was when the first invasive lionfish was recorded off the coast of Florida. People didn’t know it at the time but the sightings that were slowly starting to occur represented the birth of an ecological disaster for the reefs of the Caribbean and surrounding areas. Few could have predicted how rampantly the lionfish would come to invade and populate their new home.

Moving forward towards the present day again, some might think that the invasion has put more fish in the sea so what’s the problem? Well the problem is that there aren’t more fish in the sea, granted there are lots more lionfish but there are considerably fewer of other species. The issue is that nothing is controlling the population in their new habitat, no resident predators will kill them. The next issue is that they are gluttonous, they eat and eat and eat, the only thing they stop eating for is to breed and they do that exactly the same way that they eat – to excess, lionfish are capable of releasing up to 30,000 eggs every few days.

To summarize – lionfish are literally eating the reefs to death.

So what do we do about it? First off, we need to kill as many lionfish as possible. I can’t image we will ever manage to eradicate them from the western Atlantic but concerted efforts from the scuba diving and fishing communities can help reduce the population as much as possible. So killing them is good.

As the problem started becoming more widely documented, divers took to the oceans in their droves armed with spears and went on a killing frenzy. Many regions followed an initiative to shoot the lionfish and then feed them to native predators in the hope of introducing them into the food chain, not a bad idea, surely that makes sense doesn’t it? Unfortunately not, let me explain….

I will use Grand Cayman as an example as it is the part of the Caribbean I know best. The predators that were fed here in the past included snappers, groupers, sharks, eels and even barracuda. For the record, these all hunt and eat lionfish in their native waters of the Indo Pacific, they are just not behaviorally programmed to do so over here. The idea to feed these guys lionfish turned out to be a bad one because it proved harmful to them and divers alike.

Grand Cayman has a lionfish control program that is run by the government’s Department of Environment (DoE) which now forbids anyone feeding lionfish to marine life. Cullers are not even allowed to leave dead or dying lionfish on the ocean floor. No matter how small, any captured or speared lionfish have to be removed from the ocean, that’s the law.

But why? Surely if we are killing lionfish then whatever we do with it when it’s dead doesn’t matter? Let’s go back to the DoE and what they are tasked with, first off, their mission from their website:

The Mission of the Department of Environment is to facilitate responsible management and sustainable use of the natural environment and the natural resources of the Cayman Islands; through environmental protection and conservation, wise use, scientific research and public education.

And that pretty much sums it up, feeding lionfish to other species is reported to have a number of negative effects on the indigenous marine life and the safety of divers. Read the statement above again and the reasons behind the subsequent ban make more sense.

Furthermore, the idea to make predators eat lionfish by feeding them didn’t work anyway. Predators will happily eat a lionfish off a spear but in spite of having been fed them for years, the documented cases of them hunting the invasive creature of their own free will are very much the exception as opposed to the rule.

One negative effect of feeding dead and dying lionfish to other predators is that their behavior has been altered to their own potential risk. A good example is our friendly mutton snapper who are usually only a few feet away on every dive. They love the sound of bubbles, because to them it means food. So if someone is spear fishing while scuba diving (which is illegal in the Cayman Islands but in spite of the DoE’s best efforts, people continue to break the law) then the mutton snapper swims straight up to them hoping for a free meal but instead gets shot and dies.

The little story of the eel at the beginning of this blog is another example of how we have negatively altered behavior. When creatures act in such a way, divers who are not involved in culling lionfish may well perceive the uncharacteristic behavior as a threat. It’s no wonder that a diver may panic if he thinks something is about to take a bite out of him.

As fish continue to drop their guard and cease to see humans as a threat, it makes them vulnerable. When their interaction with divers becomes more engaged, so the divers have more chance of hurting themselves or even getting bit which in turn results in wider hostility towards the “aggressive” predator.

So if this is all known and documented then why on Grand Cayman do we sometimes see people underwater shooting lionfish without appropriate containment devices? I’d like to think that some do so because they still feel they are doing the right thing. The DoE are studying this environmental issue from a scientific point of view and plan their actions based on their findings. I guess some people either think they know better or simply haven’t had the memo.

Local diver John Ferguson happy to have his fingers after being attacked by a green eel while responsibly hunting lionfish. 

Unfortunately there are those who are motivated by other means and my only comment on the subject is this – If you are on a dive trip in Grand Cayman and your divemaster is shooting lionfish to feed to predators to make a show for you in order to boost their tip potential, what happens next is up to you. Whatever your opinion is of a divemaster putting on such a show, bear in mind that the dive op you have chosen is happy to break the law for the sake of a small financial gain, just think about that for a minute.

And why would you waste it anyway? Lionfish tastes fantastic, there are so many really cool recipes out there and you just can’t beat great tasting fresh food, especially when it is not only sustainable but also helps the reef every time you eat it. The drive to put lionfish on the menu is what is really incentivizing communities to kill more. With that in mind, even if you don’t want to take an active role in spearing lionfish, just remember that all you have to do to be a part of the solution is to eat as much of the delicious food that has been made from them as possible. The message is simple – Eat em to beat em!

About the Author: Drew McArthur is a professional dive instructor and boat captain currently working at Divetech on Grand Cayman. Since his first dive over 20 years ago, he has found himself in all kinds of underwater environments from golf ponds on the side of a snowy Welsh mountain to the tropical paradise he has now become accustomed to. A fanatic of all things tech, one of the main things Drew loves about Grand Cayman is the accessibility of such premier dive sites. Check out Drew’s blog here.

Explore the Dive Sites of the Cayman Islands with iDive!


Leave a Reply

Your email address will not be published. Required fields are marked *