[Coral-List] Red Sea Lionfishes

[Philip Karp]

Justin


Thanks for sharing.  Your finding re the primarily crepuscular browsing
behavior of *Pterois miles* is indeed interesting in the context of
lionfish control initiatives in the Western Atlantic.

As you may know, one of the notable observations about behavior of lionfish
in the invaded range is that they are being sighted throughout the day,
often in large aggregations.   This has been attributed by some to be a
function of the absense of predators.

There is recent evidence of a behavioral shift in some areas.
A study published earlier this year  (*What Doesn't Kill You Makes You
Wary? Effect of Repeated Culling on the Behaviour of an Invasive Predator) *
 http://www.plosone.org/article/info:doi%2F10.1371%2Fjournal.pone.0094248
,  Isabelle Cote, *et al* examined behavior of lionfish populations *(**Pterois
volitans/miles)* on coral reef patches in the Bahamas.  They found that on
reefs where culling by divers is being undertaken regularly, the lionfish
are becoming crepuscular in their feeding activity, hiding out in crevices
during the day and browsing at dawn and dusk, whereas lionfish on reefs
where there is no culling taking place were observed to be active
throughout the day.    I am aware of anecdotal observations of similar
behavioral change in other parts of the invaded range where culling is
being undertaken regularly.


Cote *et al* hypothesized that the change in behavior is a direct result of
the culling activity; i.e. the lionfish are adapting to the regular
spearing  and are becoming wary, hiding during the times of day that the
culling typically takes place.

Given your findings, I’m wondering whether an alternative explanation might
be that the daytime feeding activity observed on unculled reefs in the
invaded range is a function of the high densities (100+ fish ha –1 in some
areas) and associated heightened competition, necessitating more time spent
on hunting, and that the change to crepuscular behavior might be a
reversion to “normal” behavior as population density is reduced through
culling and competition lessens accordingly.



I’d be interested in your thoughts on this, as well as those of the authors
of the PLOS article (I’m copying several of them, for whom I have email
addresses, as I’m not sure whether they are subscribed to the Coral-List).


Whatever the explanation for the behavioral change, it is important, as
Cote *et al* point out, to consider the implications for culling activities
and techniques, as these are indeed proving to be effective in reducing
lionfish populations on invaded reefs, but may now need to be adjusted in
light of what is being learned about how lionfish in the invaded range are
adapting.

Sincerely
Phil Karp





Message: 4
Date: Wed, 13 Aug 2014 15:49:04 -0400
From: Justin Grubich <justinrg at gmail.com>
Subject: [Coral-List] Red Sea Lionfishes
To: "coral-list at coral.aoml.noaa.gov" <coral-list at coral.aoml.noaa.gov>
Message-ID: <95274E9D-7E62-458C-9146-D483FE503929 at gmail.com>
Content-Type: text/plain; charset=us-ascii

Hello coral-listers,

For those interested in the lionfish invasion of the Western Atlantic, my
colleague and I just published a new paper surveying lionfishes in their
native range of the Red Sea.  More to
come as well.

The link to the abstract is below.

Regards
Justin

http://www.int-res.com/abstracts/meps/v508/p223-232/