This is a response to the radiobroadcast this morning at Hooier 2 where several
people talked about lionfish. (January 26, 2010) Good presentation and I
thought it would be useful to follow up with some information that is available
from the science community that will back up or clarify certain issues that
were being discussed. As for the discussion how these fish can be kept under
control: in principles that apply here are relevant to all organisms on this
planet. Two things to keep in mind: if lionfish would be
"uncontrollable" the Indo-pacific would be full of them and that's
not the case, and two, if top predators were indeed so successful just by being
a predator our waters would be filled with scorpion- and trumpet fish, which
isn't the case either. So, these lionfish are more than likely controlled
during their earliest life-stages when larger native fish can still eat them.
For this to occur, a learning curve is likely needed during which native fish
such as groupers, trumpet fish etc. "learn" that these lionfish are
edible. Till then, the more energy is invested to keep their numbers down, the
lower their equilibrium density (i.e., the density at which they will establish
themselves on our reefs on the long run) will be. We have over-fished several
other fish species that hardly move (i.e., goliath groupers etc), so why not
this one? Attached you'll find some papers (sorry for providing the
"raw" material, and not a summary, but unfortunately time is limited
for these sort of things). To further illustrate how complicated this issue is,
I want you to keep in mind that we've all been saying that for healthy reefs we
need more predators (meaning groupers and sharks etc.). Here is a new predator,
so why is this beast not welcomed as "the new guy" that can now keep
unwanted species (i.e,, gardening damselfish species) under control that
exploded in abundance once released of their native predators (i.e., groupers/
snappers)? This staminate sort of makes sense and it sort of doesn't. We all
know invasive species bring nothing but misery and this lionfish is unlikely to
be an exception. Nevertheless, to find out how these newcomers affect the reef
on our islands, I would like to encourage especially the Curacao crowd to
please start bringing these lionfish in to Carmabi so we can check them out for
stomach contents, growth patterns, parasites and DNA analysis. My hope is that
due to the oceanic nature of our islands, lionfish might particularly target
plankton feeders (glass gobies, chromis etc) that occur in greater abundances
on our islands due to there aforementioned "open ocean nature". If
this would be true, then juveniles of more reef associated species might be
(relatively) left alone and hence the consequences for our reefs would be less
severe than say in the Bahamas (that are non-oceanic islands) where these
lionfish slaughter up to 80% of the native juvenile fish populations.
These things aren't simple and it is difficult to determine the impact of these
lionfish on such a fine-tuned ecological machine that we call a coral reef.
Data is needed to make better management decisions to eventually reduce the
impact of this newcomer.