Nature Takes its Course

[offthewall1]

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.

 

[DandyDon]

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.

Wonder how they get as big as chickens?

Cut one open sometime, and see what it ate that day.

 

[RonFrank]

Lionfish, are carnivorous.

Eating Habits
Lionfish are carnivorous, feeding mainly on crustaceans and fish. Lionfish are thought to be nocturnal hunters, but they have been found with full stomachs during the day in the Atlantic.

For someone who claims knowledge of marine life you seem ignorant. Lionfish have voracious appetites and they feed on eggs as well as adults. We need all the Sharks and Goliath Grouper we can get! For more info do a search...

http://www.cbsnews.com/stories/2009/08/25/eveningnews/main5265488.shtml

 

[smellzlikefish]

Richard,

I've spent as much time in the water as virtually any other human being...

That's a pretty bold claim, especially from someone who lives in Maryland.

I don't have to visit the Caribbean to know that lionfish are eating other fish, mostly because that is what lionfish do. Lots of lionfish eat lots of native fish. The removal of big predators may have had a very small small effect on the voracity with which the lionfish have taken over the Caribbean. If you want to see the damage an invasive species fulfilling a niche can do, visit any habitated, isolated island (Guam and brown tree snakes, Hawaii and, well, pretty much everything that lives here today). Overfishing is a huge issue and as much as I'd love to blame the lionfish invasion on a lack of predators, the dots just don't connect. The lionfish shouldn't be there in the first place.

 

[drrich2]

Researchers have examined stomach contents of dead lionfish and found native fish species in them. They are eating fish.

I concede discarded lionfish carcasses will impact the ecosystem in some way. Then again, live ones may be a detriment to the food chain that ultimately feeds higher predators, and the lionfish themselves are a 'human impact,' so there is no 'hands off' option.

Ken, I get the impression your personal views on killing fish for sport are affecting your presentation of the issue. You have a valid point that lionfish carcasses alter predator behavior, but terms like 'maliciously' and 'spear happy humans' cause you to come across to me as offended by the act of humans killing fish, rather than someone who's carefully weighed the pro.s & con.s of culling vs. ignoring this invasive species, and looking for ways to rationalize discouraging people from culling. I may be intuiting your reasoning and motivation wrongly. Some people collect the bodies of those they kill, but kill all they can - does that bother you?

Richard.

 

[Kitty_Kat]

I witnessed a large Queen Triggerfish chasing and eating a live juvenile Lionfish. So much for all the worry about Lionfish having no natural predators and this insidious hunt to exterminate them.

Very interesting! I hadn't heard of/seen a triggerfish go after a lionfish before this. I recently spent a while in the Turks and Caicos doing some research with lionfish so here's my two cents for what it's worth...

Lionfish definitely do eat native fish. We dissected quite a few and looked at the fish they were eating relative to their size and it was apparent that they are able to prey upon fish that are more than 1/2 their size (unusual), which makes them a dangerous invasive species. We did observe some grouper preying upon the lionfish, but rarely... (we did also see a couple of spiny lobsters fighting off lionfish with their barbed antennae which was humorous, but we don't think they were actually eating them) Some others that were working there had built up a relationship with the native fishermen where they would not gut any large finfish they caught at sea, and would instead give the stomachs to us upon their arrival at the docks so that the stomach contents of the larger fish could also be examined. Findings from this: lionfish constituted a negligible portion of the diet of these larger fish.

I agree completely that speared/dead lionfish should not be fed to the native fish/sharks. We made the mistake early on of spearing the lionfish that we caught, so by the end of the dive we were carrying around a net full of bloody dead fish which of course peaked the interest of a friendly reef shark. In order to preserve our comfort, this bag was surrendered to the shark. This really only makes these predators more interested in interacting with humans, which isn't a healthy relationship, and as has been seen in places such as the Mediterranean (eels), does actually endanger divers. This one shark (who happened to be distinctively scarred) that we accidentally fed repeatedly approached us for the next 6 months! After this incident, we found that nets were very effective at capturing lionfish and were a much better alternative. We did go out of our way to target lionfish for the purpose of plotting their distribution (GPS) compared to size. We found that most lionfish of intermediate size are most commonly found in the seagrass beds and mangrove habitats where large grouper/triggerfish/sharks which could prey upon them are ​not​ found. For this reason alone, I do believe that they should be targeted by people (just not fed to the local fish). They are very yummy to eat and very slow . Part of the work we did was to encourage the locals to start catching them as a part of the local fishery. Of course we realistically aren't going to be able to exterminate/remove them completely from the Atlantic... they are there to stay, but their numbers should be controlled.

Hopefully that made some sense . I'd be happy to see if I can find a publicly accessible link to some of that research if anyone is interested.

 

[drrich2]

After this incident, we found that nets were very effective at capturing lionfish and were a much better alternative.

Is that true in terms of safety? I can see some advantages, but having a live lionfish in a bag near your person, even a 'tough' bag, seems hazardous, more so than spearing it from a distance and swimming off.

Richard.

 

[offthewall1]

Richard,

There is no doubt lionfish feed on native species... they have to eat... but they don't feed on native species any differently than native species already feed on each other. Lionfish are simplky an addition to the equation. I have weighed the pros and cons. I see points for both sides. I am simply saying I now see evidence that native species are adapting to control the lionfish population.

I am not offended by humans killing fish for consumption. I'm not a vegetarian or environmentalist whacko. I believe nature is taking it's course - as it always has. The oceans have sorted themselves out for millions of years... long before people started diving. To me, the only invasive species in the oceans are humans. Fish can travel anywhere in the ocean they wish to travel. Some make longer journeys than others. Regardless, they all adapt - and have for millenia.

I see no reason to kill and collect fish? What is the purpose? I have a friend who collects lionfish for his home fish tank. This is great - and they're a beautiful fish to have in captivity. I have no problem with this. What I have a problem with is killing them in the name saving native species and leaving the carcasses laying around the reefs until a predator finds and eats them. I also don't think DM's should be spearing them and feeding sharks with them as a spectacle. I think this is impacting the balance and altering native species behavior.

I think if you're going to kill lionfish... the kill should be for consumption by you. I've heard of places where the lionfish are hunted and then served for dinner that evening. Great idea.

 

[offthewall1]

We have water in Maryland... perhaps the most beautiful bay in the world. Ever heard of the Chesapeake? We also have a short 2 hour ride to the Atlantic Ocean - ever heard of it? I also wonder if you know that ALL fish eat other fish!

Invasive species is a human term. Fish and Animals adapt to their changing environments and have for millions of years. The primary drive in the extinction of animals and fish over the past 200 years is human encroachment. We have overfished the seas and overdeveloped land once ruled by animals. Take a look around the globe. Lionfish have not been the cause.

This current drive against lionfish reminds me of the drive to eradicte sharks after the movie Jaws. Another over-reaction by uneducated humans. Nature will take it's course -

 

[MXGratefulDiver]

You have a flair for overstatement.

We have water in Maryland... perhaps the most beautiful bay in the world. Ever heard of the Chesapeake?

I've heard of it. I've seen it. It's not the most beautiful bay in the world. It's not even the most beautiful bay I've seen ... and I haven't seen very many of the world's bays.

We also have a short 2 hour ride to the Atlantic Ocean - ever heard of it?

... and this backs up your claim that you've spent as much time in the water as virtually any human being ... how? The Atlantic off the Maryland coast is undiveable for significant parts of the year. And even if it weren't, living two hours away means you're not going to be diving out there every day. There are people in the world who live two minutes from water that they dive in every day ... in some cases, all day.

According to your profile you've got less than 5,000 dives. I personally know people with three times that ... and there are people out there with way more dives than them.

FWIW - I live five minutes from a great dive site ... in a place that I consider way more beautiful than Cheasapeake Bay ... and I can count on one hand the number of people I know who dive it more often than I do on a regular basis. And I couldn't come even close to making the claim you did.

I also wonder if you know that ALL fish eat other fish!

Not true ... there are many ... many ... species of fish that eat plankton and other forms of life that are not fish.

Invasive species is a human term.

Invasive species is a human invention ... that's really rather the point. They wouldn't be there if we hadn't put them there.

Fish and Animals adapt to their changing environments and have for millions of years.

This is true ... and that adaptation works on a time scale that typically involves centuries or millenia ... not a handful of years. Humans can create ... and have created ... problems that adaptation cannot resolve. And when they have it has typically ended badly for other species.

The primary drive in the extinction of animals and fish over the past 200 years is human encroachment. We have overfished the seas and overdeveloped land once ruled by animals. Take a look around the globe. Lionfish have not been the cause.

This is also true ... but irrelevent to the problem of lionfish in the Caribbean. No, lionfish aren't the cause ... we are. And the question isn't what we can do about it ... the obvious answer to that question is "precious little". The question is what will the balance become once it's eventually achieved ... and how will it affect the reefs?

This current drive against lionfish reminds me of the drive to eradicte sharks after the movie Jaws. Another over-reaction by uneducated humans. Nature will take it's course -

The drive to eradicate sharks after Jaws was nothing compared to the ongoing drive to eradicate them for the profit their fins bring on the Asian market. That's a far greater problem than the lionfish ... and one we have total control over. Perhaps that's the problem we should be seeking to eradicate ...

... Bob (Grateful Diver)