To kill or not to kill lionfish in the Caribbean and Florida?

[kelemvor]

Hello Kelemvor - can I ask what a dremel is please

Dremel is a brand name for high speed "rotary tools." It's a hand held device with a variable speed spinning end much like a drill. Unlike a drill, the end can spin at a very high speed. The model I own goes up to 35,000 RPM. You put various attachments onto it and use it to cut, buff, grind etc. In this case I was thinking of using a grinding bit to smooth off the barb on my spear. It would probably take 4 or 5 minutes to complete.

8220 12vmax High Performance Cordless - dremel.com

There are many brands of rotary tools these days but Dremel is a ubiquitous name for the device. Much in the same way that all personal watercraft are often called "Jet Ski" even though Jet Ski is a brand name owned by one company.

 

[CT-Rich]

My understanding is that not only are they voracious and wiping out small and juvenile fish but also contribute to coral destruction by dramatically reducing important herbaceous fish which corals rely on to control algae. Spearing and deep water trapping seems to be important in mitigating their destructive effect on reefs until a more effective means of control is found.

An interesting study here suggests that sound production by lionfish might be helpful in monitoring and perhaps ultimately controlling populations. Also agree getting larger predatory fish like grouper and sharks to start identifying them as prey items is part of the long term solution in achieving balance. I'm not sure how you do that without actually feeding them to the larger fish...perhaps leaving some speared lionfish on the reefs while also culling others for people food..?

Interesting thought here.. How do you "teach a fish about a prey item"?

Most fish do not care for their young, so while you could coax a shark or grouper into eating something that it not a normal prey item, it isn't going to show it to it children and say "try these, they are yummie." Would this training go past the one or two animals that you show it too? Granted, a few sharks or groupers hovering up any LF they run across would be goood for the reef, but would this work as a self-sustaining solution? A good time for some one like Dr Bill to chime in...

 

[boulderjohn]

Seven days of diving in Cozumel last week and the only LF I saw was on my plate at La Perlita!

They are down below normal recreational depths. I haven't dived Cozumel in about 5 years, but when I was there last, at 200 feet they were plentiful and BIG.

 

[Russell Bowyer]

My understanding is that not only are they voracious and wiping out small and juvenile fish but also contribute to coral destruction by dramatically reducing important herbaceous fish which corals rely on to control algae. Spearing and deep water trapping seems to be important in mitigating their destructive effect on reefs until a more effective means of control is found.

An interesting study here suggests that sound production by lionfish might be helpful in monitoring and perhaps ultimately controlling populations. Also agree getting larger predatory fish like grouper and sharks to start identifying them as prey items is part of the long term solution in achieving balance. I'm not sure how you do that without actually feeding them to the larger fish...perhaps leaving some speared lionfish on the reefs while also culling others for people food..?

Good points, I guess then having sharks take them from the spear as I experienced may be a good thing????? However, does this teach them to eat lionfish or to associated feeding with divers. Not sure.

The sound production is an interesting concept, is a specific sound that somehow only affects lionfish?

 

[Russell Bowyer]

Here you go... https://www.dremel.com/en_US.

I am a bit confused at this site Mike, as it shows drills and the like, not sure how these are associated to a speargun and protecting the reef?

 

[drbill]

Yes although I think total extirpation of the species is highly unlikely. The damage they do to these ecosystems is substantial. In the past I oversaw the extirpation of feral goats from an island ecosystem they had ravaged for centuries. It was not without concern we did that, but the greater concern was the harm they did to the many native species.

To me the health of the many native species in an ecosystem wins over the survival of an invasive non-native species (speaking as a marine ecologist).

 

[Russell Bowyer]

Yes although I think total extirpation of the species is highly unlikely. The damage they do to these ecosystems is substantial. In the past I oversaw the extirpation of feral goats from an island ecosystem they had ravaged for centuries. It was not without concern we did that, but the greater concern was the harm they did to the many native species.

Thank you for your input Dr Bill, it';s a difficult one and you are so right, as the first time I got involved with killing lionfish, which was in Barbados, I finished the dive not feeling too good. It was a long time since I'd ever killed anything and it left a bad taste for sure. However, 'man' as always interferes with nature and unfortunately to the detriment of the indigenous population. Which is how I justified my actions.

I agree with you though, it's highly unlikely the species will ever be eradicated totally, they are so intertwined and breed so proliferatously, I think they are in the Caribbean and surrounding seas to stay.

 

[drbill]

I agree with you though, it's highly unlikely the species will ever be eradicated totally, they are so intertwined and breed so proliferatously, I think they are in the Caribbean and surrounding seas to stay.

Indeed their reproductive potential is a major factor in their success. Even if we could eradicate all of them in diving depths, they have a refugium in the deeper waters which can replenish what is taken in shallower waters.

 

[Russell Bowyer]

Dremel is a brand name for high speed "rotary tools." It's a hand held device with a variable speed spinning end much like a drill. Unlike a drill, the end can spin at a very high speed. The model I own goes up to 35,000 RPM. You put various attachments onto it and use it to cut, buff, grind etc. In this case I was thinking of using a grinding bit to smooth off the barb on my spear. It would probably take 4 or 5 minutes to complete.

8220 12vmax High Performance Cordless - dremel.com

There are many brands of rotary tools these days but Dremel is a ubiquitous name for the device. Much in the same way that all personal watercraft are often called "Jet Ski" even though Jet Ski is a brand name owned by one company.

Okay - I now understand - thank you for clarifying

 

[Russell Bowyer]

Indeed their reproductive potential is a major factor in their success. Even if we could eradicate all of them in diving depths, they have a refugium in the deeper waters which can replenish what is taken in shallower waters.

Actually, do we know what depths they will go to, as Boulderjohn talks about 200 feet, I must admit I thought they had a tendency to be in the shallower reefs up to around 20-40 metres (65-130 feet). But I guess I am mistaken?