[Coral-List] An Observation

Dennis Hubbard dennis.hubbard at oberlin.edu
Sat Feb 2 17:37:35 EST 2013


Thanks Alina:

I was wondering how long you could stay away from this one. You have more
fortitude than I.

By way of historic perspective, Alina was one of the first to weigh in on
this in a significant way a decade or so ago. While we were arguing about
the relative importance of "top-down" versus "bottom-up" controls (soon
joined by the "side-in" folk in a free-for-all that was reminiscent of the
recent US Congress), for some reason that always escaped me, nutrient
loading got the short stick. What we now take for granted (nutrients count
and all algae are not created equal) is largely the result of many very
careful field (and a few good lab) studies in which nutrients were
manipulated to show the effects of things that were largely tied to
anthropogenic factors compared to pathways that went through algal turfs.

Sorry to be so surreptitious.

Dennis

On Fri, Feb 1, 2013 at 11:58 AM, Szmant, Alina <szmanta at uncw.edu> wrote:

> I just checked in quickly to see what this was all about, and don't have
> time to paste in references.  It seems this discuss is ignoring decades of
> excellent research on the role of nutrients on coral-algal interactions,
> different types of reef algae etc.  Before writing any more rather
> uniformed opinions, go read the papers published (most of them based on
> field studies, and in combination with lab studies), over a decade ago by,
> just to get you started,  Larkum, McCook, Diaz-Pulido, McClanahan, Stimson,
> and even myself.
>
> *************************************************************************
> Dr. Alina M. Szmant
> Professor of Marine Biology
> Center for Marine Science and Dept of Biology and Marine Biology
> University of North Carolina Wilmington
> 5600 Marvin Moss Ln
> Wilmington NC 28409 USA
> tel:  910-962-2362  fax: 910-962-2410  cell: 910-200-3913
> 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 Jon Skrapits
> Sent: Friday, February 01, 2013 9:45 AM
> To: coral list
> Subject: [Coral-List] An Observation
>
> Hey Dennis,
>
> Agreed that diving isn't a boondoggle. I was merely implying that it takes
> many dives to learn about eutrophication and the impact of nutrients on a
> reef vs setting up an aquarium and seeing the effects in short
> order(weeks). Granted, the learning curve of aquaria hasn't been that great
> either. Many corals and fish have perished from a lack of understanding how
> to care for them. However, now I farm 600 species of hard and soft coral
> while other commercial operations farm clownfish and many other species in
> favor over wild harvest. Money is made but lessons are learned fast because
> of that. When variables are in question for studying animals in their
> natural or non-natural enviornment it is surely difficult to be 100%
> accurate but..... If I release fido to the wild he is more likely to perish
> because of domestication while fish may have this issue corals most likely
> do not. Aquaculture should be supported more and considered to be a more
> viable source for scientific information because you must create a
> "perfect" enviornment for the corals to thrive. Corals can be placed back
> into the wild and be minimally stressed if the ocean they are idigenous to
> is accepting.
>
> Also, you are right. I am aware that the two algae are different and I have
> seen where coralline is a requirement of a healthy ecosystem. It is useful
> or even required for micro algae to flourish on top of the coralline which
> promotes grazing by the herbivores. Surgeonfish will pick at the coralline
> all day when there is nothiung to be seen by human eyes yet they are very
> healthy and almost obese. This seems to be very true in the genus
> Ctenocheatus I have never seen a healthy aquarium that had macro algae
> growing amongst the corals/rocks. In fact, when I see clumps of bryopsis
> and other macro algae, the herbivores are very thin in most cases and
> sometimes suffer from HLLE(head and lateral line erosion) or other symptoms
> of malnutrition. The fix in aquaria is to cut back on nutrient introduction
> even though it would seem the answer is to feed the fish more. That is
> actually the cause of the ecosystem collapsing. Cutting back nutrient
> introduction while balancing chemistry(specifically Ca and Mg of course the
> ocean does not have this issue) allows coralline to grow and allows the
> fish to naturally graze. This also keeps the water column clean unless
> there is an excess of nutrients. This is why I suggest non-harvest as a
> dangerous path. It takes weeks/months to fix this in aquaria but how long
> is the healing process in the wild? Decades? Longer?
>
> I always ask this question: Are the Elkhorn and Staghorn Acropora
> rebounding since they were listed? Mariculture efforts are being done but
> if the ocean isn't accepting, why are we trying to force it? If
> preservation is the key, we need to study them as fast as possible and come
> up with solutions to change our habits. I am sure we agree on that but the
> disagreement comes when aquaculture/aquaria is discarded as a hobby and not
> looked at as a possible way to learn about these animals fast. Why not make
> grad students keep an Acropora alive in a small aquarium? Better yet, get
> it to grow over a semester. That will teach them much because they will
> soon find that the ecosystem needs to be a bit more complete in order for
> the Acropora to grow.
>
>
> On Fri, Feb 1, 2013 at 9:01 AM, Dennis Hubbard
> <dennis.hubbard at oberlin.edu>wrote:
>
> > Hi John:
> >
> > While agree with your point about the error in assuming that banning
> > corals in tanks will not save them, I'm not sure that allowing them in
> > tanks will have any greater measure of positive impact. Also, I'm not
> sure
> > I'd characterize an afternoon dive to take measurements or conduct
> > experiments as a boondoggle (even though that's not what I do for a
> > living). There has always been tension between the fact that you just
> can't
> > do controlled experiments in the wild versus significant scaling issues
> in
> > microcosms. Both have serious flaws, but as long as we acknowledge them,
> I
> > think we're on sound footing.
> >
> > Walter Adey showed the pattern described in your citation 30 years ago
> > and, unfortunately, I have not seen it prominently acknowledged among all
> > the back-and-fort over the years about the role of nutrients (although
> I'm
> > sure many on the list can point me to such references within their
> > specialty journals). One small point (and probably just an unintended
> > juxtaposition in your post) - coralline algae (second para) and turf
> algae
> > (cited in first para) are not the same organisms. I mention this only
> > because I see the two conflated in the literature and am aggravated by
> the
> > fact that so many "experts" get this wrong.
> >
> > Dennis
> >
> > On Thu, Jan 31, 2013 at 10:22 PM, Jon Skrapits <
> > jon at treasurecoastcorals.com> wrote:
> >
> >> Listers,
> >>
> >> >From the link:
> >>
> >> "An overall negative relationship between fleshy macroalgae and
> >> slow-growing reef-building organisms (i.e. scleractinians and crustose
> >> calcareous algae) was recorded, suggesting competition between these
> >> organisms. The opposite trend (i.e. positive relationships) was recorded
> >> for turf algae and the two reef-building organisms, suggesting
> beneficial
> >> interactions and/or co-occurrence mediated by unexplored factors. Turf
> >> algae cover increased across the region between 2006 and 2008, while
> >> scleractinian cover showed no change. The need of a continued and
> >> standardized monitoring program, aimed at understanding drivers of
> change
> >> in community patterns, as well as to subsidize sound adaptive
> conservation
> >> and management measures, is highlighted."
> >>
> >> I see this everyday in my aquaculture facility. Eutrophication plays a
> >> much
> >> bigger role than some things discussed in the die off of reefs. The
> amount
> >> of excess nutrients needed for macro algae to become dominant over micro
> >> or
> >> calcareous algae is very small. A line crossed easily in aquaria. It is
> >> not
> >> apparent in the wild to the human eye when looking at turbidity. If you
> >> can
> >> see the turbidity it is already way past the point of a healthy balance.
> >> It
> >> takes skill to see elevated nutrients it in an aquarium where there is
> >> little debris in the water. If coralline algae is to grow, it needs
> little
> >> competition from macro algae because they can out compete coralline. The
> >> reef (ecosystem)needs micro algae to filter the water daily with the
> light
> >> and nutrients available, leaving the water clear for better photo
> periods.
> >> Then die at night and relase waste into the water for polyps and
> >> zooplankton to feed. At least this is what I suspect from my farming
> >> operations obeservations.
> >>
> >> Banning corals from the aquarium trade will not save them. We can learn
> >> much more from these animals and how they live from laboratories. An
> >> afternoon dive seems to be a bit of a boondoggle in comparison but is
> >> needed.
> >>
> >>
> >>
> http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0054260
> >>
> >> --
> >> Thanks,
> >>
> >> Jon Skrapits
> >> Treasure Coast Corals, Inc.
> >> Grow em instead of leaving em.
> >> _______________________________________________
> >> Coral-List mailing list
> >> Coral-List at coral.aoml.noaa.gov
> >> http://coral.aoml.noaa.gov/mailman/listinfo/coral-list
> >>
> >
> >
> >
> > --
> > Dennis Hubbard
> > Dept of Geology-Oberlin College Oberlin OH 44074
> > (440) 775-8346
> >
> > * "When you get on the wrong train.... every stop is the wrong stop"*
> >  Benjamin Stein: "*Ludes, A Ballad of the Drug and the Dream*"
> >
>
>
>
> --
> Thanks,
>
>
>
>
>
>
>
> --
> Thanks,
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>
>
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>



-- 
Dennis Hubbard
Dept of Geology-Oberlin College Oberlin OH 44074
(440) 775-8346

* "When you get on the wrong train.... every stop is the wrong stop"*
 Benjamin Stein: "*Ludes, A Ballad of the Drug and the Dream*"


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