[Coral-List] Coral bleaching in American Samoa

Kelley Anderson kelley at climatefoundation.org
Mon Dec 7 19:58:07 EST 2009

Hi All,
Thanks to Al for his helpful reminder.  I will post if more paling/bleaching
is seen.

The paling pattern I am seeing looks the same as what I observed at the end
of the bleaching season last season.  I conducted some experiments in April
'09 and found the coral capable of recovering it's color rapidly if the
temperature is reduced by as little as 1 degree C, confirming that the
bleaching is at least partially driven by the thermal stress despite the
dorsal bleaching pattern.  That said, the observed bleaching patterns agree
with your suggestion of photically induced paling and I agree that the added
photic stress results in the dorsal pattern of bleaching that I observed.

The area I observed the paling is inside the reef crest and more than likely
not included in your satellite images.  Perhaps you could point me to where
I can learn more about how far the land mask extends for your #8 station on
Tutuila?  I would like to see the area covered in your images that the SSTs
are derived from.

Many thanks,

On Mon, Dec 7, 2009 at 12:34 PM, Alan Strong <Alan.E.Strong at noaa.gov> wrote:

> Thanks for your observations Kelley,
> http://coralreefwatch.noaa.gov/satellite/virtual_stations/graphs/vs_multiyear_exp_Tutuila.png
> Note above our (CRW) virtual station SST time series for Tutuila (off
> Fagatele Bay) over the past decade...this year's SSTs are the line in solid
> black.  Although many of the values over this decade have indeed been
> running over the climatological mean SSTs (derived from 1985-1993) they are
> not yet even close to what we (Coral Reef Watch) would even warrant issuing
> a bleaching "watch" or "warning."  What it is likely that you are seeing are
> the coral polyps' response to the sun's increasing energy as it gets
> progressively higher in the sky each day -- what you are likely seeing is
> referred to as "paling" and a more normal response of corals at this time of
> the year as the SSTs and isolation ramps upward.
> Cheers,
> Al
> Kelley Anderson wrote:
>> Hi all,
>> I was out in the shallows (less than .5m depth at low tide) just east of
>> the
>> Pago Pago airport off of Nuuli and saw some bleaching on the dorsal
>> portions
>> of the horizontal branches of *Acropora nobilis*.  This appears to be the
>> first signs of bleaching seen this season.  With our regular coral
>> bleaching
>> surveys on hiatus while our coral ecologist is off island, I will post
>> another update if more bleaching is seen.
>> Cheers,
>> Kelley Anderson
> --
> **** <>< ******* <>< ******* <>< ******* <>< ******* Alan E. Strong, Ph.D..
>  NOAA Coral Reef Watch, Consultant  Strong Research, Inc. & AJH
> Environmental Services  National Oceanic and Atmospheric Administration
>  NOAA Coral Reef Watch Program  e-mail: Alan.E.Strong at noaa.gov  url:
> coralreefwatch.noaa.gov
> E/RA31, SSMC1, Room 5311  1335 East West Hwy  Silver Spring, MD 20910-3226
>  301-713-2857 x134               Fax: 301-713-3136  Cell: 410-490-6602

·´¯`·.¸. , . .·´¯`·.. ><((((º>`·.¸¸.·´¯`·..¸.·´¯`·...¸><((((º>

Kelley L. Anderson, M.Sc.
Marine Scientist
The Climate Foundation
American Samoa
"If the biota, in the course of aeons, has built something we like but do
not understand, then who but a fool would discard seemingly useless parts?
To keep every cog and wheel is the first precaution of intelligent
tinkering."  Aldo Leopold

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