Lionfish In The Bahamas

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I'm also a "crazy" educator. Everything archman has said is right on. Invasive species are the biggest threat to our natural ecosystems next to maybe habitat destruction.
 
bikefox:
I'm also a "crazy" educator. Everything archman has said is right on. Invasive species are the biggest threat to our natural ecosystems next to maybe habitat destruction.

With all due respect, I have a few questions and comments about this concept in general. First I agree that in cases like the sea lamprey, or tilapia in the Florida waterways, that eradication is beneficial. But now it's too late.
But as I mentioned earlier, there is a large unknown gray area. How do you define "invasive species"? First you would have to determine what species are indigenous in any given habitat, which may not be fully completed anywhere. I mean down to the insect/crustaceans and even mocroscopic organism which can greatly affect the food chain. Once that's complete, how often do you "police" the area to search for "invasive species"? Yearly? Every five years? And if you do determine that they're there, do you start an eradication program? How costly is that? And what about overlapping areas due to geographical proximity? How about the case of subtropical species of fish off the San Diego coast due to the warm water moving north from the El Nino? This must occur in rather massive doses every 20 years or so. Maybe I'm missing something here but this seems incredibly complicated to me. It may be a noble effort but I believe it's next to impossible to accomplish.
And finally, it seems that this concept has gone full circle from the bad lessons we learned about trying to INTRODUCE exotics to enhance a given habitat. We will now try to stop natural changes in predominate species that has occured throughout the history of the world in order to preserve what is there? Mother Nature hasn't accomplished this yet and maybe there's a reason.
I'm a farmer and we've gone over the introduction of pro biotics into systems over and over. And basically everyone now agrees that introduction won't work without changing the environment itself, (temperature, salinity, nutrient balance etc) because whatever likes the existing environment best, will flourish. And as the seas change, so will predominate species in any given area. (some more than others obviously due to more or less constant envronmental parameters) Oh, and a guy I work with here says the lionfish have been seen off the Carolinas and as far north as New York for at least 6 years. Maybe too late anyway to get rid of them Archman. Sounds like they're established. Just a simple farmer's view, Hank
 
Hank49:
How do you define "invasive species"? First you would have to determine what species are indigenous in any given habitat, which may not be fully completed anywhere. I mean down to the insect/crustaceans and even mocroscopic organism which can greatly affect the food chain. Once that's complete, how often do you "police" the area to search for "invasive species"? Yearly? Every five years? And if you do determine that they're there, do you start an eradication program? How costly is that? And what about overlapping areas due to geographical proximity? How about the case of subtropical species of fish off the San Diego coast due to the warm water moving north from the El Nino? This must occur in rather massive doses every 20 years or so.
You seem to have a pretty good grasp of the key problems. Yes, it IS complicated. But there are several "quick and dirty" methodologies that work reasonably well.
1. Baseline Surveys of Habitat: This tells you what's native and what's not. Most ecosystems "of interest" have these now. They will all vary in their level of "completeness". They are never considered fully complete, but key indicator species are almost always tagged. That's good enough for government work.
2. Policing For Exotics: Generally this is only done in areas that currently have a lot of exotics, and are either being monitored or actively removed. Those areas have special funding and personnel allocation for that task. There are a LOT of wildlife areas within the United States with this sort of protection.

For areas with no known exotic problem, there are usually no formalized patrols. Exotics are identified as they appear in newer surveys, or when John Doe the Weekend Naturalist happens to come across one while he's out camping. Folks like this provide invaluable support.

3. How do you know its an Exotic?: Many exotics stick out like a sore thumb, and are no problem. For others (i.e. lookalikes), it takes observation and specimen collections to verify. Two sorts of people do this latter work, biologists, and local nature buffs.

In order for an animal to be a "true exotic" vs. a mere range extension, it typically needs to hopscotch other habitats between its native home and its new home. This is a dead giveaway for monitoring folks. They usually are decently versed on species from adjacent habitats, and can recognize them when they intrude in from time to time. But when some plant or animal pops up that's not only not native, but not even a neighbor, alarm bells go off.
This is why El Nino intruders aren't a problem. They're more like unruly neighbors overstaying their welcome. Immigration to adjacent habitats is what the weenie biologists term "beta diversity", and is usually not a big deal.

And finally, it seems that this concept has gone full circle from the bad lessons we learned about trying to INTRODUCE exotics to enhance a given habitat. We will now try to stop natural changes in predominate species that has occured throughout the history of the world in order to preserve what is there? Mother Nature hasn't accomplished this yet and maybe there's a reason.
Unlike history, politics, and fashion, science rarely repeats itself. We gain more information over time, and the old data is far more difficult to forget. The scientific method and peer review is pretty stern about performing background research. Thus many scientists can be said to have a better grasp of history than historians.

So its quite rare for us to go full circle in repeating bad decisions from the past. If we make any crappy choices, they'll be brand new ones.:wink:

As to stopping natural gamma-scale immigration (what most people consider exotic intrusion), that's impossible. Best case, we can slow it down. Which actually is more "natural", given the sheer increases brought about by man within the last few centuries. Not doing anything to slow down exotics is ecologically a very bad idea, as the majority of ecosystems are not designed to handle the high immigrant influxes they are currently experiencing. In some areas its like a floodgate. Entire habitats are being destroyed, as we speak. Intrusive exotics tend to reduce biodiversity, and disrupt community structure. If they replace a keystone species or bring along a nasty disease, things can get really icky.

The Earth is currently experiencing a global mass extinction event, except this one is manmade. No biologist disputes this. We may dispute climate change, but not the primary causal agent for extinctions. People are to blame. But what makes this extinction event irritating is the speed at which it is occurring. Exotics play a key part in this. With moderate amounts of work however, some of this can be slowed or managed. Which is what many wildlife managers in parklands and reserves currently do.

I'm a farmer and we've gone over the introduction of pro biotics into systems over and over. And basically everyone now agrees that introduction won't work without changing the environment itself, (temperature, salinity, nutrient balance etc) because whatever likes the existing environment best, will flourish. And as the seas change, so will predominate species in any given area. (some more than others obviously due to more or less constant envronmental parameters)
The environmental change thing is more of a fatalistic viewpoint. Politicians and the lay public like it 'cuz it means they don't have to do anything. But nobody has any good predictions as to how that will operate, and in the meantime, ecosystems are getting thrashed. Blaming the bulk of this on "natural processes" is almost universally poo-pooed by every biologist that ever lived. Just look at fishing pressures, coastal development, deforestation, pollution... the list goes on and on.

Damaged ecosystems are absurdly easy to recognize by ecologists, PROVIDED there is a baseline survey to compare with. There's distinct markers in community structure.

Aquaculture ops are one of the worst direct ecology-damaging influences known. Unless the effluent systems are almost completely self-contained (quite rare), they function as giant poo and chemical toilets dumping into the local watershed. The outfits that culture non-native species are playing with fire. Relatively few aquaculture operations are green-lighted by ecologists, as their damage potential usually tops the list. I do not know anything about Belize-specific operations, however. Governments with draconian water quality regulations have the safest aquaculture programs. And they're expensive as heck to operate.

Oh, and a guy I work with here says the lionfish have been seen off the Carolinas and as far north as New York for at least 6 years. Maybe too late anyway to get rid of them Archman. Sounds like they're established.
yeah, I know the guy that does a lot of the ROV monitoring. But that's the east coast population. I'm more concerned with the sightings in the Bahamas. The longer we can keep them out, the longer the native Bahamian ecology can recover from manmade damages. Healthy ecosystems are far tougher on intruders than damaged ones. Less chinks in the armor.

Hank, stop asking me such complicated questions. Look at all this crap I had to write! Aren't there any ecologists down there you can harass?! My fingers hurt.
 
archman:
Hank, stop asking me such complicated questions. Look at all this crap I had to write! Aren't there any ecologists down there you can harass?! My fingers hurt.

Not only that...I thought you were coming to Belize to argue about this. :D I think we do agree somewhere in the middle but maybe a little to either side of the fence. I agree that doing nothing to help the environment is not good but meddling too much is also not good. Science can be trendy. (as when they thought introducing species was good) (no offense) It's rewritten all the time based on new discoveries. And don't EVEN get me going on aquaculture. I've been at it for 28 years and the statements about how bad it is are also outdated. We're aware that destruction of the environment is bad. Why would we destroy the very medium we need to make money? (oops...."make money".... that's a bad thing to say :D ) I know, some places, it's bad but the industry is well aware of the problems. Come and see this farm. Now about those lion fish......Later Amigo and thanks for your valuable inputs.
 
Hank49:
. Science can be trendy. (as when they thought introducing species was good) (no offense) It's rewritten all the time based on new discoveries.
Well to be fair, a trend is nothing more than a popular course of action. Trends occur in every field as a matter of course. It's repetition of trends that science rarely engages in, unless they are particularly good ones supported by more recent advances. This continual forward progression separates science from most other disciplines.

At the time, current science favored (grudgingly) combating exotics with exotics. The field of Ecology was in its infancy back then, or worse. Community structure and function were almost complete unknowns.

Oceanography also was a near complete unknown around the same time, in the early 1950's. Even more so was Genetics, Virology, Endocrinology... the list goes on and on. Except for Natural History, Taxonomy, General Anatomy and a few others, the field of Biology is essentially less than a century old.

Back in the 1980's, there was a semi-popular saying.
"99% of all scientists that ever lived are currently still alive".

In 2005, that saying is still fairly accurate. We've lost a few percentage points, probably. A lot of taxonomists have died and not been replaced. Criminal.
 
But perhaps this is repitition. Every generation feels that they know more than the previous. We see this in our children and this can be very frustrating. Although today's scientists have MORE knowledge, acting on the knowledge only to find out later that it wasn't such a great idea after all, must be avoided or in a sense, it IS repititious. "With every new door that's opened, we find four or five more". It hasn't changed. There is still so much to learn. And although many marine bio PhDs have vast knowledge of what exists and perhaps how it came to be, few were successful at aquaculture. My point being, is if they know so much about Mother Nature and her ways, then culturing a single or polyculture pond should be a piece of cake. But it's not. If we can't even do this without glitches and hitches, how is it that we think we can control nature in her wild, natural state?
I hate the destruction of our forests and reefs. Don't get me wrong. And I would love to see alternative fuels, recycling, recirculation of water used in multiple stages etc etc. I think we just have to be careful and not jump on a bandwagon too quickly. This is the dangerous repititon, and the reason I was shooting African (I believe) cattle egrets off our shrimp ponds in Hawaii 20 years ago.....hey, we DO agree here. Blowing away the exotics. I watched one of them swallow a baby pheasant....whole. Well, I guess it deserved it. It was ANOTHER exotic...so I got two in one shot. Yeah, Hawaii is a classic example of exotics ruining the natural state. But it's unique in that it's so isolated and easy to verify. (dude, you have to come to Belize. This converstion could go on for years.)
Amazing how a little lionfish( I had a cute little one that loved monodon post larvae from our hatchery) can stimulate this conversation. Happy Thanksgiving Archman. Hank
 
Hi all,

This is a very interesting topic, and it happens to be one of my areas of expertise, so I will pitch in if I may.

Hank, I completely agree with you that we have to differentiate between natural and human-mediated invasions. In one of the previous posts someone said that it is very difficult to demonstrate a natural invasion. Well, I (with the help of some colleagues) just did that using DNA sequences, if you are really interested in the subject you can download my most recent publication here:

http://plaza.ufl.edu/rocha1/publi.htm

Having said that, there are several factors that clearly indicate that the lionfish introduction was human-mediated:

1) It is an extremely popular aquarium fish that grows a lot, and people are usually hesitant (understendably) to kill their pet fish when they grow too large for their tanks.

2) The nemo effect: a few weeks after the release of the wildly popular movie "Nemo", several Pacific marine fishes started being spotted off the coast of Florida. Guess what, people started freeing their nemos.

3) The Bahamas and Florida are the most well known marine region in the world. If we know about the fish fauna of somewhere, it is Florida and the Bahamas.

4) The Lionfish is a very charismatic animal, and we know its distribution very well.

5) The only possible way for this fish to invade the Atlantic naturally is coming around South Africa from the Indian Ocean. The species in the picture appears to be Pterois volitans, which does not occur in the western Indian Ocean, but I can't be 100% sure by only looking at the pictures.

Now, when we have so much evidence that this was a human-mediated invasion, I am all in favor of the kill'em all philosophy. This would be different if instead of lionfish, the presumed invasive was some goby that was not in the aquarium trade and couldn't survive in a ship's ballast water. Why? Because if it's got there naturally it has what it takes to get there, sooner or later.

I hope I have contributed to the dabate. Happy thanksgiving all!

Luiz
 
Rocha:
Now, when we have so much evidence that this was a human-mediated invasion, I am all in favor of the kill'em all philosophy. This would be different if instead of lionfish, the presumed invasive was some goby that was not in the aquarium trade and couldn't survive in a ship's ballast water. Why? Because if it's got there naturally it has what it takes to get there, sooner or later.

I hope I have contributed to the dabate. Happy thanksgiving all!

Luiz

I agree on the killing of obviouse intruders (invasives). The gray, difficult area is....well...gobies for instance. The ones that hide in holes...or....ever try to find a ghost pipe fish? Ichthyologists are still identifying new species. The job of trying to observe and log indigenous species in a 100 meter sq area of coral reef is difficult enough. Try 10,000 sq km. But what a fun job.....diving every day looking for hard to find frog fish, pipe fish.....sign me up. :D
 
Hank49:
Every generation feels that they know more than the previous. We see this in our children and this can be very frustrating.
Yes, I know exactly what you are referring to. However, in the sciences we have a much better claim to this than anybody else. The scientific method requires full disclosure of experimental protocols, so that they can be repeated for verification. This is an enormously powerful too.

Although today's scientists have MORE knowledge, acting on the knowledge only to find out later that it wasn't such a great idea after all, must be avoided or in a sense, it IS repititious. "With every new door that's opened, we find four or five more". It hasn't changed.
Well yes, it has changed. When one has more information available to them, he/she will statistically make better choices. The likelihood of failure drops. Look at Dr. Rocha's paper using genetics. That's a tool we didn't have 20 years ago. It allows us to better differentiate populations. We rarely use it without traditional methods to back it up, but few can argue against its value.

As to the door reference, the key difference between today's science and yesteryear's is that we've already passed through the older doors. To us, a "door" represents a hypothesis to be tested. As we do this, our questions become more specific; these become the future pathways we must take.

Other disciplines cannot match the sciences with this consistency of forward progression. They are neither designed nor required to.

And although many marine bio PhDs have vast knowledge of what exists and perhaps how it came to be, few were successful at aquaculture. My point being, is if they know so much about Mother Nature and her ways, then culturing a single or polyculture pond should be a piece of cake. But it's not. If we can't even do this without glitches and hitches, how is it that we think we can control nature in her wild, natural state?
Ah, I see the difficulty right now (I minored in mariculture). Aquaculture is INCREDIBLY complicated. Yes, I know a lot of lab weenies think it's "merely" fish farming. They're talking out of their butts. They are not qualified to comment on the field; ignore them and the lay public. What you folks do never gets enough respect... it's not like you're growing corn.

Artificial propagation/growout of species in unnaturally dense concentrations... that's rough. The "rules" of natural biology often don't work properly (or are too hard to manage) with aquaculture. You require an exact order and preciseness of flow in order to succeed. Natural ecosystems do not function this way. Aquaculture is NOT easy.[/QUOTE]
 
Alright. It's been great this talk. And I'm sold on the concept of eliminating exotics and invasives. Although it's a daunting task and your fighting an uphill battle all the way, I would love to work in this endeavor but it's probably "bring your own dive gear and we'll feed you" type pay. And since I have one more to get through college I'll have to keep beating up on myself growing shrimp till I can scrounge enough to retire in a decent shack in the swamp. In the mean time I'll spear any dogtooth tunas, humuhumunukunukuapua'as etc etc, and especially those pesky lion fish I see here in Belize. Later amigo, Hank
 
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