Lyngbya

[Ursula Keuper-Bennett]

Dear Dr. Tibbets (and others interested)

Thanks for your response.

You wrote:

>My lab has also worked with Stylocheilus. It is a remarkable consumer of
>Lyngbya and has fantastic growth rates. Unless we can identify and close
>down the causal factors in bloom generation they offer one of the few
>potential biological control agents.

They're lovely humble little creatures --and they're welcome to the 
Lyngbya.  But we've found that they don't limit themselves to 
Lyngbya.  When out in full force, Stylocheius litter the ocean bottom and 
infest everything --including conventional turtle forage.

Their numbers are astounding.

You wrote:

>I'd be keen to know if you got any Haminoea (anbother mollusc) in the bloom
>and if you noted large numbers of Metis (a large red harpacticoid).

The only other mollusc we notice along with the Stylos are what look to be 
Plakobranchus ocellatus (closest thing I can find in any books).  They're 
fairly common --meaning easy to find some on each dive, but that's about 
it.  Sand-camouflaged-coloured you'd barely notice they're about.

As for have I noticed large number of large red harpacticoids I had to 
check what they were.  It seems harpacticoids are copepods and copepods are 
supposed to be tiny --so your "large" comment has confused me!  When I 
checked further, I found a Moreton Bay document referring to Metis and 
harpacticoids at:

   <http://www.botany.uq.edu.au/research/marine/publications/pdffiles/literatureandrew.pdf>

Your research group, perhaps?  It's a wonderful informative document by the 
way but it makes no mention of what "large" means for a large, red Metis.

The only thing I remember as being slightly red were these tiny "bugs" 
somewhat smaller than the period on your keyboard.  Cladophora sprigs 
simply CRAWLED with those things... easy to see their round reddish bodies 
against the green even with my poor close-up vision.

Not knowing what they were I called them "spider mites" because that's what 
they reminded me of.  The Cladophora was filthy-alive with them.  I'm 
embarrassed to say I never thought of looking in the Lyngbya for them.  But 
the Lyngbya and Cladophora were so intertwined --here's an example

   <http://www.turtles.org/limu/lynghalihyppnclad2000rspld.jpg>

-- it's likely the "spider mites" would also call Lyngbya home.  (Note I 
did examine Lyngbya and found Stylocheilus and also tiny crustaceans.)

OK, now I have a few questions for you.

In your document it states, "Lyngbya majuscula has shown to be an essential 
part of the diet of the pomacentrid damselfish, Stegastes apicalis.  I 
checked out what fish that was and it's a kind of gregory.

At our dive site we have Stegastes fasciolatus and there's something we 
noticed this summer.  Almost all the larger (older-looking ones) had lumps 
on their fins --juveniles didn't.  Do you know what those lumps are?  Are 
your Moreton Bay Stegastes "lumpy" as well?

These lumpy fish are in the area where the Lyngbya has the greatest 
concentration and grows right up and among the corals --that's why I'm asking.


Thanks for your time and best wishes on your important research.

Ursula Keuper-Bennett
TURTLE TRAX
<http://www.turtles.org/whoswho.htm>
-------------------------------------
At 06:58 AM 6/19/01 +1000, you wrote:
>Dear Ursula Keuper-Bennett (and possible others who will get this),
>
>I am part of a team looking at the Lyngbya blooms in Moreton Bay,
>Australia. We have a large population of green turtles here that seem to be
>succumbing to fibropapilloma. We are planning a small research project to
>look at turtle health, Lyngbya toxin loads in turtles and the effects of
>Lyngbya on their food. While Lyngbya has been around for a very long time
>it does seem to be increasing its frequency and severity of infestation.
>
>I have seen it on the GBR but in relatively low biomass and very patchily
>distributed.
>
>My lab has also worked with Stylocheilus. It is a remarkable consumer of
>Lyngbya and has fantastic growth rates. Unless we can identify and close
>down the causal factors in bloom generation they offer one of the few
>potential biological control agents.
>
>I'd be keen to know if you got any Haminoea (anbother mollusc) in the bloom
>and if you noted large numbers of Metis (a large red harpacticoid).
>
>Cheers, Ian
>Dr Ian Tibbetts
>Lecturer in Fish Biology
>Director Moreton Bay Research Station
>Director International Studies
>Centre for Marine Studies

~~~~~~~
For directions on subscribing and unsubscribing to coral-list or the
digests, please visit www.coral.noaa.gov, click on Popular on the
menu bar, then click on Coral-List Listserver.