[Coral-List] mysterious Tridacna mortality

[Ulf Erlingsson]

This may be of relevance: We have places SediMeter instruments off Miami in about 2 to 5 m of water, without cleaners. The instrument measures the accumulation of algae etc on the sensor. It is detectable after already 24 hours, and by the naked eye after about 5 days. I would guess that by the time the instrument "sees" it, it would also be possible to feel it as being slippery rather than squeaky clean. For what it's worth.

Ulf Erlingsson
Lindorm, Inc.

On 2012-03-26, at 21:22, Bill Allison wrote:

> An elementary forensic question:
> 
> Has anyone noted how quickly an algal film begins to be apparent on the
> inside of a tridacnid shell after it has been killed and left in the water
> with the shell open with the inside facing upwards (i.e, well lit).
> This becomes detectable with the unaided eye on a dead coral here in about
> a week.
> The shells I saw were squeaky clean.
> 
> On Mon, Mar 26, 2012 at 5:44 PM, Bill Allison <allison.billiam at gmail.com>wrote:
> 
>> I am finding unusual numbers of T. maxima and T. crocea shells lying loose
>> on the reef of a resort under construction.
>> The shell are still hinged, there is no shell breakage or obvious scrape
>> marks and their interiors are clean (no epibiota). I suspect human agency
>> because the usual suspects are here in unusual numbers and I have not
>> observed this in other instances when only the natural predators such as
>> titan triggerfish are present.
>> Suggestions welcome.
>> Thanks.
>> Bill
>> 
>> 
>> --
>> ________________________________
>> "... the earth is, always has been, and always will be more beautiful than
>> it is useful."
>> William Ophuls, 1977. The Politics of Scarcity
>> 
>> 
> 
> 
> -- 
> ________________________________
> "... the earth is, always has been, and always will be more beautiful than
> it is useful."
> William Ophuls, 1977. The Politics of Scarcity
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