Lion Fish, an increasingly serious threat

[Hank49]

Here in the Keys a few restaurants have them on the menu. Based on these stats there could be issues with Ciguatera poisoning

It would seem logical that if the lion fish in Puerto Rico are positive,(or where ever they are testing positive for ciguatera), that other reef predators would also be testing positive within that given area. Jacks, large grouper, snapper, moray eels etc.
To my knowledge, ciguatera seems to be regional based on whether or not the dinoflagellate is prevalent or not. If the dino is there, a high number of the predators will be positive.
Or am I missing something here?

 

[Doc]

Likey, yes, very regional, and just for that reason. I think the study was done in Cayman, USVI or Bahamas.

It would seem logical that....

It is more of a species specific kind of critter, heretofore only suspected often in Barracuda, at least for the find of Caribbean fish that we are likely to eat.

Wiki: Ciguatera is a foodborne illness caused by eating certain reef fishes whose flesh is contaminated with toxins originally produced by dinoflagellates such as Gambierdiscus toxicus which lives in tropical and subtropical waters. These dinoflagellates adhere to coral, algae and seaweed, where they are eaten by herbivorous fish who in turn are eaten by larger carnivorous fish. In this way the toxins move up the foodchain and bioaccumulate. Gambierdiscus toxicus is the primary dinoflagellate responsible for the production of a number of similar toxins that cause ciguatera. These toxins include ciguatoxin, maitotoxin, scaritoxin and palytoxin. Predator species near the top of the food chain in tropical and subtropical waters, such as barracudas, snapper, moray eels, parrotfishes, groupers, triggerfishes and amberjacks, are most likely to cause ciguatera poisoning, although many other species cause occasional outbreaks of toxicity. Ciguatoxin is very heat-resistant, so ciguatoxin-laden fish cannot be detoxified by conventional cooking.[1][2]

And guess what predator species is now at the very tippy-top of the Caribbean food chain?

Read more: http://nolionfish.com/2010/09/lionfish-and-ciguatera/
http://nolionfish.com/2011/01/lionfish-and-ciguatera-the-facts-have-changed-2/
http://coral.aoml.noaa.gov/pipermail/coral-list/2011-January/009583.html

and of course, The Fraternal Order of Lionfish Slayers:

http://www.facebook.com/pages/Fools-Fraternal-Order-Of-Lionfish-Slayers/101557233257490

 

[Hank49]

A prominent ichthyologist once told me of a study done on the dinoflagellate in the Pacific. He said that the dino is much like a lichen which is one of the first organisms to appear on a new lava flow after it cools.
Gambierdiscus, and ciguatera poison cases became prevalent around many Pacific islands after WW2. The US dynamited surrounding reefs to get material to build air fields, exposing new layers of the fossilized coral which produced optimum conditions for the dino to grow on. As the exposed calcium carbonate aged and other organisms (coral, algae, anemones etc) began to dominate, the dino began to disappear.

 

[b-dog]

It would be nice if people just left the lionfish alone and just appreciated their beauty because they are a truly beautiful fish. Without the top predator fish the lionfish just assumes their role of eating smaller fish. With time things will balance out and the lionfish will become part of the marine ecology in the Caribbean and Atlantic. The overfishing is of much bigger concern than the lionfish.

 

[diverdoug1]

It would be nice if people just left the lionfish alone and just appreciated their beauty because they are a truly beautiful fish. Without the top predator fish the lionfish just assumes their role of eating smaller fish. With time things will balance out and the lionfish will become part of the marine ecology in the Caribbean and Atlantic. The overfishing is of much bigger concern than the lionfish.

b-dog, your 2 posts, disregard species displacement and ecosystem tipping points. An invasive species that feeds on juveniles (such as the Lionfish) can easily stop the repopulation of other predators, even if overfishing was stopped. Things will balance out, but the balance will likely be very different than it previously was. There could eventually be species displacement or extinction of many of the caribbean species. An efficient, non-descriminating, rapidly reproducing predator can sterilize an ecosystem. I also do not feel that spearfishing can make a significent impact on Lionfish populations, if for no other reason than Lionfish habitat is minimally covered by areas frequented or accessable to recreational divers. Humans have demonstrated the ability to harvest a fish species to extinction in certain areas (like the Blue Walleye), but effective Lionfish capturing modalities have not been devised, and are not economically motivated at this time. If Lionfish start to account for a larger portion of the harvestable biomass, they may start to be veiwed more favorably as tablefare, and an economic impetus may develop for widespread harvest. If this comes to pass, reintroduction of native species may be possible, but not guarunteed. With respect to Ciguatera toxin, it is found in varing levels in all reef species, but Lionfish consumption would have a lower risk of poisoning than Grouper consumption in the same habitat, secondary to the prefence of Lionfish for predation on juvenile and smaller prey items. Your statement that overfishing is a much bigger concern is foolhardy, because overfishing can be controlled much more easily than the spread of an invasive species. Overfishing is an ear infection that can be cured with antibiotics (removal of economic encentive by banning sale, and high fines for harvest), whereas the invasive species is a cancer which may never be cured.

 

[b-dog]

b-dog, your 2 posts, disregard species displacement and ecosystem tipping points. An invasive species that feeds on juveniles (such as the Lionfish) can easily stop the repopulation of other predators, even if overfishing was stopped. Things will balance out, but the balance will likely be very different than it previously was. There could eventually be species displacement or extinction of many of the caribbean species. An efficient, non-descriminating, rapidly reproducing predator can sterilize an ecosystem. I also do not feel that spearfishing can make a significent impact on Lionfish populations, if for no other reason than Lionfish habitat is minimally covered by areas frequented or accessable to recreational divers. Humans have demonstrated the ability to harvest a fish species to extinction in certain areas (like the Blue Walleye), but effective Lionfish capturing modalities have not been devised, and are not economically motivated at this time. If Lionfish start to account for a larger portion of the harvestable biomass, they may start to be veiwed more favorably as tablefare, and an economic impetus may develop for widespread harvest. If this comes to pass, reintroduction of native species may be possible, but not guarunteed. With respect to Ciguatera toxin, it is found in varing levels in all reef species, but Lionfish consumption would have a lower risk of poisoning than Grouper consumption in the same habitat, secondary to the prefence of Lionfish for predation on juvenile and smaller prey items. Your statement that overfishing is a much bigger concern is foolhardy, because overfishing can be controlled much more easily than the spread of an invasive species. Overfishing is an ear infection that can be cured with antibiotics (removal of economic encentive by banning sale, and high fines for harvest), whereas the invasive species is a cancer which may never be cured.

Granted they are an invasive species and there does not seem to be any way of getting rid of them. So feel free to kill them if it makes you feel happy. But I just feel there are many worse things to worry about like oil spills in the ocean and pollution from rivers and garbage dumped into the ocean. If there were more groupers and snappers there would be less lionfish. And in the Pacific there are many lionfish and the fish live just fine there. But kill all the lionfish you see if that is your dream.

 

[diverdoug1]

If there were more groupers and snappers there would be less lionfish.

I am not trying to pick on you b-dog, but this statement is also a bit off. Since Lionfish prey on the juvenile stage of the adult prey items Grouper and Snapper feed upon, a larger population of said Grouper and Snapper species would not be likely to limit Lionfish population growth or expansion. Once predator/prey equilibrium is reached, the Lionfish population will cause the other predator's prey species to continuously diminish. Eventually predation pressure will effectively "sterilize" the predation cycle, resulting in death or displacement of predators in the ecosystem. In an evolutionarily derived predator/prey ecosystem (like the one in the Pacific you mention), this process is usually cyclical or stable (because of varying degrees of successful survival strategies of prey species resulting in a residual breeding stock, and eventual return of prey numbers high enough to support predator populations). In the instance of an invasive predator, the system can be irrevocably disturbed. In the case of lionfish, the juvenile species that they are preying on will likely not have adequate time to evolve avoidance / survival behaviors for Lionfish predation in the short time it would take for the Lionfish to decrease prey species to the extinction tipping point (the point at which a species population is too low to propagate in a particular niche). In response to your implication killing the Lionfish may be a dream of mine, it would make very happy if any solution to this blight on the Caribbean could be found (but as I said in my original posting, I do not think spearing is the answer). Your impassioned feelings regarding the importance of protecting the environment are admirable. Unfortunately, the clarity of the expression of those feelings is muddied when you mix that message with misinformation.

Here is a NOAA Gif for the expansion of Lionfish sightings form 1992 to 2011. http://nas.er.usgs.gov/taxgroup/fish/Lionfishanimation.gif

 

[Hank49]

It will be interesting to see what fish are depleted or greatly reduced by lionfish. Some fish are fast learners and once exposed to a predator, like a spearfisherman on scuba or free diving, it's hard to get close to them again. Snappers, most groupers (blacks, yellow fin, red, tiger), even some jacks. But others are really dumb and haven't learned that humans are dangerous predators. Hogfish, Nassau groupers to name a few.
I would guess those are the ones in real danger.
Just a thought here.....in Belize we have an annual whale shark migration where the sharks come just at the time when huge schools of snappers are gathered and spawning en mass at Gladden Spit. The sharks cruise right though the huge clouds of egg and sperm just released by snappers and gobble up the eggs by the millions. Compared to lionfish cruising the reefs, the whale sharks seem to be much more a threat to snapper survival, yet this has been going on for thousands of years. like I said....just a thought....