Nature Takes its Course

[Guba]

Let me be upfront...I don't live close to an ocean. I don't have a huge number of dives. I'm not a trained marine biologist (though I AM a biologist), and I am not an expert on lionfish. However, I do teach environmental science, and I do know a thing or two about the phenomenon we call "invasive species", all of which share some common characteristics. Generally, invasive species have a rapid reproductive rate, they are very adaptable, and they--through that adaptability or just the luck of the draw--have the ability to out-compete similar native species. Lionfish fit all of these criteria, and one additional thing that can be said for invasive species...once introduced and established, they WILL NOT BE ERADICATED. I cannot think of a single example in which a prolific invader was successfully removed by human intervention. That said, I'm not against efforts to remove as many of the invaders as possible. We do the same thing with countless other invaders. However, one must approach this effort with a sense of reality...we are NOT going to be able to get rid of the lionfish. The best we can hope for is the same thing farmers and ranchers in my area achieve with one of our own local invasive species, the mesquite tree. We can try our best and use huge amounts of resources and effort to keep the mesquite out of our farmland and pastures, but if we let up on those eforts for any appreciable amount of time, they're back. We can do the same with the lionfish, expending great amounts of effort to thin them on our favorite dive sites and in marine sanctuaries, etc...but we will never be able to have a lasting significant effect on their success in their new envirnment. It's a hope that we can "buy time" by lending a hand while native species learn to avoid and/or predate upon lionfish, but that's pretty optimistic.
As others have noted, I'm more concerned about what the lionfish's success means in regard to the way we use the ocean's resources. Is the lionfish so successful because of something we are doing to the indigenous species? Is overfishing playing a role in this situation? Is the lionfish not really a villian but instead a "canary in the coal mine"? I think these are valid questions and I feel they are more far reaching than the issue of whether it's good or bad to spear the little pests. The answers could well be a sobering wake-up call that does not need to be ignored.

 

[MXGratefulDiver]

Let me be upfront...I don't live close to an ocean. I don't have a huge number of dives. I'm not a trained marine biologist (though I AM a biologist), and I am not an expert on lionfish. However, I do teach environmental science, and I do know a thing or two about the phenomenon we call "invasive species", all of which share some common characteristics. Generally, invasive species have a rapid reproductive rate, they are very adaptable, and they--through that adaptability or just the luck of the draw--have the ability to out-compete similar native species. Lionfish fit all of these criteria, and one additional thing that can be said for invasive species...once introduced and established, they WILL NOT BE ERADICATED. I cannot think of a single example in which a prolific invader was successfully removed by human intervention. That said, I'm not against efforts to remove as many of the invaders as possible. We do the same thing with countless other invaders. However, one must approach this effort with a sense of reality...we are NOT going to be able to get rid of the lionfish. The best we can hope for is the same thing farmers and ranchers in my area achieve with one of our own local invasive species, the mesquite tree. We can try our best and use huge amounts of resources and effort to keep the mesquite out of our farmland and pastures, but if we let up on those eforts for any appreciable amount of time, they're back. We can do the same with the lionfish, expending great amounts of effort to thin them on our favorite dive sites and in marine sanctuaries, etc...but we will never be able to have a lasting significant effect on their success in their new envirnment. It's a hope that we can "buy time" by lending a hand while native species learn to avoid and/or predate upon lionfish, but that's pretty optimistic.

I think we should try marketing ... if we could somehow convince the Chinese that Atlantic lionfish are an aphrodesiac, they'd be gone in a year.

As others have noted, I'm more concerned about what the lionfish's success means in regard to the way we use the ocean's resources. Is the lionfish so successful because of something we are doing to the indigenous species? Is overfishing playing a role in this situation? Is the lionfish not really a villian but instead a "canary in the coal mine"? I think these are valid questions and I feel they are more far reaching than the issue of whether it's good or bad to spear the little pests. The answers could well be a sobering wake-up call that does not need to be ignored.

I suspect that the reason the lionfish are so successful isn't because the adults lack predators, but because the fry don't. It's a numbers game ... lionfish are prolific reproducers, as are most fish. They lay over 2,000 eggs at a time ... several times a year. Fish tend to reproduce by the thousands because the chances for their babies to grow up to be adults are incredibly slim ... in a typical clutch, usually only a few will make it to adulthood. The rest get eaten ... either while they're still eggs or shortly thereafter. Without that high mortality rate, their numbers quickly increase to the point where they start crowding out other species in a competition for available food supply ... which is what's happening. Once they reach adulthood, it doesn't matter how many predators they have ... they can reproduce faster than they can get eaten ... which is also what's happening.

My previous comment about marketing was meant in jest ... but the fact is that the only way to reduce the population by going after the adult fish is to make them a commercial product and develop a means to catch them in numbers that are as high as or higher than the reproduction rate ... and I don't see any way to achieve that without significant collateral damage to other species.

So my take on the whole mess is that we're pursuing the problem from the wrong angle ... we need to figure out how to keep them from breeding so fast ... if that's even possible.

... Bob (Grateful Diver)

 

[Caxy Diver]

The scorpion fish and Lionfish are from the same family, they also are one of the know predators. Both are cannibalistic.

 

[offthewall1]

What an amazingly ignorant thing to say.

Nature doesn't suddenly create predators and restore ecological niches in three years ... it takes decades at best, and usually centuries for all the interrelated species in a food chain to find a natural balance.

As for the triggerfish ... so, if they find a new food source, what's that going to do to the triggerfish population? And how's that going to affect the species that they normally eat? For that matter, how will it affect the species that eat triggerfish?

No single species lives in isolation ... and when a predator finds a new prey, it affects more than just those two species ... ultimately it creates changes in the entire food chain.

That's how nature works ...

... Bob (Grateful Diver)

Bob, we agree on something... I think you've made my points for me. Nature takes it's course... has for millenia without human interruption. It's actually amazing how arrogant we are as a species... thinking we have all the answers and can fix all the earths ills... we are the cause of the mess - not the cure.

 

[Guba]

"I think we should try marketing ... if we could somehow convince the Chinese that Atlantic lionfish are an aphrodesiac, they'd be gone in a year." Bob

Bob, that was one of the first comments I made a couple of years ago when a similar thread popped up. Isn't it strange that human interdiction can kill off 70 million sharks a year and drive some shark species to the brink of extinction, and yet the possibility of eradicating lionfish in the Atlantic is almost certainly zero?
However, it might be worth a try to start a "whisper campaign" to get the Asian market to at least TRY lionfish sushi in order to pep up the ol' libido. Can't hurt (or can it)?

 

[smellzlikefish]

It might be a bit more realistic to market lionfish flesh to the american people with a quick peer-reviewed publication in a medical journal praising its health benefits.

 

[Mike]

Richard,

You're right and wrong. Most killed (by spear happy humans) lionfish are quickly consumed by predators. I have watched Groupers and Sharks happily remove dead lionfish from the ends of pole spears.

My biggest concernwith this is that in essence - we are feeding the fish and the fish are adapting to "expected" meals. On my recent trip both the sharks and groupers followed us around because they are getting use to the free meals of speared lionfish. This is no different then taking the sharks a steak. Most experts don't think feeding the wild animals is a great idea. Not the bears in the woods and not the sharks in the sea.

We could debate all day whether this is a good idea or not.

I am not convinced Lionfish are a problem on reefs anywhere. What I am convinced of is that humans have overfished the reefs everywhere - to the point that there are very few fish left and there are no big fish left anywhere. The introduction of lionfish just happened to have coinicided with a drastic reduction of fish due to overfishing. Its much easier to blame tyhe lionfish then to blame ourselves.

I've spent as much time in the water as virtually any other human being... and I have yet to witness a Lionfish eating another fish... but I have observed quite a few other things killing and eating them.

Lionfish certainly are eating other fish.

But I totally agree with you about feeding lionfish to other fish. We need to stop. Kill em and leave the bodies, don't hand feed other marine life. Just dump the bodies and let the find them on their own.

Better yet kill a lionfish and drop it's dead body in front of another lionfish. If there is any truth to other species will 'learn' to hunt lionfish, let's teach lionfish to eat each other!

 

[Danielle's_Dives]

whew, This post digressed a bit since it's start. However, thanks for the positive thoughts on not hand feeding the lionfish to other fish and those who pointed out that Trigger fish and Scorpion fish have developed a liking for the Lionfish. It makes me feel a little positive that there may be hope in controlling these pesky guys in Tropical waters where they shouldn't be.

 

[supergaijin]

Coming from New Zealand I can honestly say that animals introduced to a new ecology poses absolutely no threat for the the native flaura and fauna. Offthewall deserves some sort of prize I think.

In NZ forests people routinely kill anything which has fur and doesn't fly. If it fits that description, try to kill it. It won't fix the problem but it may give the critically endangered indigenous animals a bit more time.