Are we HELPING the lionfish?

[fdog]

My background is in chemistry and phsyics, so I am somewhat clueless when it comes to perturbing natural systems.

I'm looking for an authoritative opinion here, like someone with a M.S. or Ph.D. in marine biology. All the rest of us can only speculate - heck, I can speculate - let's hear something that's not speculation.

From what little I've read, the introduction of an invasive species initially spikes in population quite steeply; eventually, they will denude the food sources, or overpopulate themselves, and the population will reduce. After time the population will stabilize. Kinda like this:

However, we are hunting these suckers. By applying predation pressure as the lionfish population is on the rise, are we deepening and strengthening the breeding stocks, and causing the following effect?

...Are we helping them?



All the best, James

 

[redacted]

I would think the population will still approach the same steady state balance point unless we are actually successful in lowering that point through continued influence. Like a teaspoon of salt in a cup of water; eventually it will dissolve and be homogeneous. Stirring just hastens the process.

I suspect any lowering of the steady state balance point will be very local and temporary since they reproduce prolifically, spread widely with the currents and feasible hunting methods are inefficient, at best.

 

[Rainer]

Is there even any evidence that human action is having *any* significant effect on curbing the lionfish population/spread?

 

[Adrian Manise]

Darned good question, and I can only speculate! It would seem your graphs depicting merely the delay of the inevitable would be the only 'evidence' we have to go on. Here's a thought though - if we have any effect at all given their prolific reproduction capacity - might it be to only weed out the dumb ones that present themselves to clumsy divers with stonage projectile weapons? Surely in the long term their behaviour will adapt to accomodate this new predation threat. I hope the current efforts towards teaching groupers and sharks to eat them has some success - but who would want to eat spikey horrible stingy things like that? Clearly they are not appetising to Groupers or Sharks or we would have to force feed them to make them eat them.

 

[Puffer Fish]

Humans have one really good skill, we are excellent at destroying things...and kind of average at putting things back the way there were.

It would be reasonable to expect the original curve to be slowed down and the normal equilibrium population to be smaller. Well, unless we really get into eating them, and can overfish them...

 

[Mike]

How is the sampling done? If you think about it the sampling method is really important to the outcome of the results.

How would you sample the lion fish population in the Caribbean and what could you actually determine?

Let say you sampled around Cozumel. The west side is the easiet to sample, the east side would actually be considered dangerous to sample from. So if you sampled the west side at all the popular dive sites you get one result, if you sampled the east side you'd get another result wildly different since no DMs are culling on the east side...