FW: Dust and Disease on the Great Barrier reef

Hi Alina (and others),

John Walch and I discovered a white nudibranch in Malaysia that also =
eats coral and using its gills to look like bleached coral polyps.  So =
check to make sure they are flatworms because these looked like =
flatworms when their gills were not extended.  They were tiny, but you =
could barely see them with the naked eye when they were forced out of =
the corals on the walls of the research aquariums we were working in.  I
=
have photos if anyone is interested.

Thanks,

Todd R. Barber
Chairman, Reef Ball Foundation
CEO, Reef Ball Development Group, Ltd.
6916 22nd Street West
Bradenton, FL 34207
941-752-0169 (Office)
941-752-0338 (Direct Line)
941-752-1033 Fax
941-720-7549 Cell
reefball at reefball.com
http://www.artificialreefs.org
http://www.reefball.com
http://www.reefball.org

  ----- Original Message -----=20
  From: Alina M. Szmant=20
  To: Julian Sprung ; coral-list at aoml.noaa.gov=20
  Sent: Wednesday, October 30, 2002 11:29 AM
  Subject: Re: FW: Dust and Disease on the Great Barrier reef

  Hi Julian and others:

  We have come across a small flatworm in our aquaria that we suspect of
=
having eaten many of our juvenile corals.  They are only a mm or so in =
length and would not be noticeable to the un-aided eye of a diver.  We =
found them with high quality dissecting scopes.  They are full of =
zooxanthellae, and we found them crawling over our settlement plates =
with empty coral spat calices.  We've also seem nematodes feeding on =
coral tissues.  There are a lot of microscopic things out there killing
=
corals, it appears!   If any of you know what some of these tiny =
critters are, I'd appreciate help in IDing them.  I do have some =
photographs.

  Alina Szmant

  At 08:38 AM 10/30/02 -0500, Julian Sprung wrote:

    Thanks for the article and links Gene. For what its worth, white=20
    syndrome-like outbreaks in Acropora in aquariums are often =
associated with
    pathogenic bacteria, and their occurrence and rate of damage is =
affected by
    temperature (high temps promote them).

    Slow-progressing bottom-up tissue loss is sometimes not caused by =
disease
    but by predators instead. Reasearchers who study Caribbean Acropora
=
are
    familiar with the coral eating snails Coralliophila, whose affect on
=
the
    corals is often mistaken by casual observers for disease. In =
aquariums with
    Indo-Pacific Acropora there are occasionally similar snails such as
    Drupella, which fortunately don't reproduce and can be removed =
fairly
    easily. There are also nudibranchs such as Cuthona that leave dead =
white
    patches on coral, but these affect mainly Montipora and Porites.

    There is one predator of Indo-Pacific corals in aquariums (and =
presumably in
    the wild too) that often goes unnoticed, though its affect can be =
dramatic.
    The beast is Scutus cf. unguis, a black limpet that I'm sure occurs
=
on the
    Great Barrier Reef. These limpets are active at night only and do =
not stay
    near the coral during the day, so researchers diving during the day
=
wouldn't
    ever associate it with the dying coral. In aquariums Scutus has the
    unfortunate habit of reproducing prolifically, so its effect can =
blossom,
    and result in the loss of all small polyped corals.

    I mention this here because the comment in the article, "it takes =
months to
    kill a large colony" sounds like it may be a predator. It may also =
be a
    disease, but the researchers involved should check the corals at =
night just
    to rule out Scutus.

    Sincerely,

    Julian Sprung
~~~~~~~
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