[Coral-List] Lionfish in the news

[mtupper]

Steve and Doug,

I think that whether or not lionfish removal from small areas could boost
grouper and/or snapper recruitment through predation release would depend on a
couple of things, such as:

1. Do the grouper or snapper species in question have specific nursery habitats
that are spatially restricted? If yes, then removal of lionfish from those
nursery habitats could conceivably reduce predation on the young of year enough
to boost recruitment. If no, i.e. the juvenile grouper or snapper are habitat
generalists and are spread out over a large area, then removal of lionfish from
small reef areas is unlikely to affect predation and subsequent recruitment
success.

2. What is the depth at which grouper and snapper juveniles typically recruit?
For species like Nassau grouper, red hind, grey snapper, etc., the depths at
which young of year recruit are well within diving depths and so lionfish
removal from juvenile habitat may be feasible. For other commercially important
species such as red or vermilion snapper, the juveniles recruit at depths of 50
m or more, which is too deep for diver removal but certainly within the depth
range of lionfish.

Steve also raises a valid point about snapper and grouper declines. These
declines have occurred from decades of fishing pressure and environmental
degradation. Some of the hardest-hit populations (e.g. Trinidad) are in areas
where lionfish have still not gained a foothold. That of course does not in any
way lessen the threat that lionfish currently pose.

Cheers,
Mark


Dr. Mark Tupper
Coastal Resources Association
2503-13618 100 Ave, Surrey, BC, Canada V3T 0A8
www.coastal-resources.org
Email: mtupper at coastal-resources.org
Tel. +1-778-903-6420


> On January 27, 2014 at 11:34 AM Steve Mussman <sealab at earthlink.net> wrote:
>
>
> Doug,
> I believe the article raises more questions than it answers.
> The most obvious issue may be related to the size of the reef areas involved
> in the study:
> "A typical reef site, which is about a third the size of a basketball court"
> . . ONE THIRD THE SIZE OF A BASKETBALL COURT?
> How does a study carried out on such infinitesimal areas of reef apply to
> the issue as a whole? It is one thing to control lionfish on these small
> parcels, but how do you apply the same techniques effectively to vast areas
> of reefs many of which are at depths below which divers can even access?
> The article also implies that the main reason for grouper and snapper
> declines is lionfish . . . wonder how they came to that conclusion?
> Steve
> -----Original Message-----
> >From: Douglas Fenner
> >Sent: Jan 25, 2014 8:33 PM
> >To: coral list
> >Subject: [Coral-List] Lionfish in the news
> >
> >Title: "Invasive Lionfish, the Kings of the Caribbean, may have met their
> >match." (put the emphasis on "may have") I noted the statement at the end
> >of the article that invasive species now cost the U.S.A. $120 billion
> >dollars a year. That's "billion" with a "B." (many or most of the species
> >that add to that cost are terrestrial or fresh water)
> >
> >http://news.yahoo.com/invasive-lionfish-kings-caribbean-may-met-match-01160
> 0208.html
> >
> >Older stories:
> >
> >"Caribbean's native predators unable to stop aggressive lionfish population
> >growth"
> >
> >http://www.sciencedaily.com/releases/2013/07/130711172538.htm
> >
> >The IndoPacific Lionfish Invasion (tons of info)
> >
> >http://www.coris.noaa.gov/exchanges/lionfish/
> >
> >REEF lionfish research program
> >Be sure to check the expansion of the lionfish in the map on this page, the
> >expansion clearly continues, now covers the entire US eastern seaboard,
> >Bermuda, Caribbean to the eastern end, and Gulf of Mexico. It takes a
> >minute to load, but it continues to 2013.
> >
> >http://www.reef.org/lionfish
> >
> >--
> >Douglas Fenner
> >Contractor with Ocean Associates, Inc.
> >PO Box 7390
> >Pago Pago, American Samoa 96799 USA
> >
> >phone 1 684 622-7084
> >_______________________________________________
> >Coral-List mailing list
> >Coral-List at coral.aoml.noaa.gov
> >http://coral.aoml.noaa.gov/mailman/listinfo/coral-list
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