[Coral-List] About time?: No its not

Szmant, Alina szmanta at uncw.edu
Wed Oct 11 17:33:02 EDT 2006

Hi Jamie et al:

I do not understand your comment about the Kuffner et al 2006 paper.
For one there is no mention of any nutrient effects of any kind.  Thus
the patterns of algal distribution and biomass that these authors report
are what are found out there but there are no data to show that they
have anything to do with nutrient (or grazing) levels.  The areas they
surveyed are directly offshore of where Florida Bay water exits onto the
Florida reef tract and are best characterized as hard bottom.  There has
been little coral and lots of sediment on those hard bottom over
Holocene time frames (reviewed by Ginsburg, Shinn and others)

Secondly, if you read the paper carefully and study the figures, their
results show that some (not all) algae have a small but variable effect
on coral settlement.  In some cases there was more settlement in
treatments with the algae, in some not, thus not a strong indictment of
algal inhibition of coral settlement. Furthermore, while some of the
differences between treatments were statistically significant the
differences were not biologically/ecologically significant given natural
variability in coral settlement patterns.  My work has shown a strong
preference of several species of coral larvae for the undersides of
field conditioned substrates (Szmant and Miller 2006, 10th Coral Reef
Proc) regardless of presence of macroalgae. In fact, larvae avoid
surfaces covered by algae, encrusting inverts, and some types of
crustose corallines too.  They mostly settle on microfilm and there is
plenty of that available at the scale of a coral larva, even when
macroalgal cover is high.  

The likely negative effect of macroalgal cover on coral recruits likely
shows up later when the corals grow out of their cryptic settlement

I know that excess nutrient enrichment, as well as too little grazing,
as well as too much grazing, can all damage small corals, affect reef
substrate composition etc etc etc.  But I hate to see the literature
misquoted for any reason, and your post is a perfect example of how easy
it is for scientists to prostitute the literature.  This is not
acceptable scientific behavior and should be avoided even if the
intention is laudable (e.g. to deter people from polluting coastal



Dr. Alina M. Szmant
Coral Reef Research Group
UNCW-Center for Marine Science 
5600 Marvin K. Moss Ln
Wilmington NC 28409
Tel: (910)962-2362 & Fax:  (910)962-2410
Cell:  (910)200-3913
email:  szmanta at uncw.edu
Web Page:  http://people.uncw.edu/szmanta

-----Original Message-----
From: coral-list-bounces at coral.aoml.noaa.gov
[mailto:coral-list-bounces at coral.aoml.noaa.gov] On Behalf Of Dr. James M
Sent: Tuesday, October 10, 2006 2:40 PM
To: coral-list at coral.aoml.noaa.gov
Subject: [Coral-List] About time!

Dear Ilsa & Devon,

Congrats on a thorough well put together manuscript! It is about time 
that these data are beginning to get published, I will use this for 
my class this next semester.

The sad point is that the people that think urchin grazing and other 
dwindling herbivores/landscapers swimming on reef system control the 
algal lawns that smother corals.  This says to the developers that 
claim  "hey our point source" that is spewing secondary treated 
sewage out into a reef is not the reason for the reefs to become 
algal dominated, its because the spiny urchin died off that used to 
be a proficient landscaper and kept the corals "macro-algae free".

Devon what I am not saying that top down controls are not 
significant, they are. However, what I am trying to say is that the 
levels of nutrients that induce algal blooms cannot be controlled 
with more grazers.

Cheers, James

Dr. James M. Cervino, MS, Ph.D.
Marine Pathology
Department of Biological & Health Sciences
Pace University New York NYC
Phone: (917) 620-5287
Web site: http://www.globalcoral.org
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