[Coral-List] Fwd: How can we "bleach proof" transplanted coral nurseries?
swooldri23 at gmail.com
Thu Aug 24 19:03:10 EDT 2017
All very relevant points!
I don't pretend to have the answers.
What of transplanting/growing the corals into already established (wild)
seaweed beds that have space-invaded inshore areas where corals have died
from bleaching (or otherwise)? - so called phase-shifted (algal dominated)
locations. Make use of the natural (seemingly from human eyes) 'bad'
>From 'bigger global picture' perspective - i actually have serious ethical
doubts as to the merit of spending millions of research dollars on coral
restoration (the scale problem, restored areas of a few 100m2 versus loss
of coral reefs ecosystem - 1000km2)
Unless someone can convince me otherwise, i think research funding is
better directed towards
developing new sources of harvestable protein. Pessimistic yes - but i
worry about the social upheaval in areas like the coral triangle that
awaits as corals ecosystem continue to collapse and fish stocks plummet.
Establishing community-size projects that develop sustainable protein (e.g.
sea cucumbers?) are probably of much much greater important at this late
stage in events.
On Fri, Aug 25, 2017 at 6:01 AM, Damien Beri <beridl at g.cofc.edu> wrote:
> Most of the algae used in the aquarium industry have the potential to
> become some serious exotic species. Example: chaeto, caulerpa. And some
> macro algae have more preference for different nutrients. One article
> based on Ulva and Chaeto in Peel inlet Australia showed that ulva uptakes
> way more N than P whereas the opposite is with chaeto. In this case a
> combination of the two would correct for excess runoff, however the two
> compete for light and chaeto always wins.
> Also, when used in aquariums the algae is ALWAYs separated by physical
> barrier because of the ability for it to spread and smother corals, clog
> pumps, and flood your home. Some coral nurseries have shown bundles of
> chaeto smothering outplanted corals which would be the equivalent to the
> hazards of placing macro into the main display of an aquarium.
> When macro algae competes against itself, self shadowing has the potential
> to release deleterious compounds into the water as the bottom layers of
> macro decay.
> Lower water flow caused by dense macro algae mats also causes
> Cyanobacteria outbreaks, fungal, and bacterial outbreaks as a result. It
> must be pruned.
> I do believe there should be massive turf scrubbers at every single outlet
> of every single runoff near coral reefs, the key is to figure out how to
> work with the existing macro algae present, or even the phytoplankton
> present as growing phytoplankton to feed corals converts N and P to coral
> Some aquarists use dosing mechanisms to take water out of the aquarium and
> fill a phyto culture which absorbs N and P and then dose the phyto right
> back into the tank to feed corals. You consume N and P through growing
> phyto from aquarium water then dose the live home grown phyto back into the
> There are also products which provide us state for fungus to grow called
> "Algon" which readily consumes N and releases a smelly sulfur gas. It's
> probably got bacteria in there too.
> Also, if a refigium is your main nutrient export in aquaria, it has to be
> at least 20% of the aquarium volume to work effectively.
> Sent from my iPhone
> > On Aug 23, 2017, at 11:35 PM, Scott Wooldridge <swooldri23 at gmail.com>
> > Sorry, it was remiss of me not to also include mention of an excellent
> > experiment by Ted McConnaughey (2000) in which he meticulously measured
> > a aquaria setting) the beneficial impact of non-calcareous algae in
> > promoting coral health under modern ocean conditions.
> > https://www.researchgate.net/publication/319255771_
> > In the experiment, he showed that the noncalcareous alga Chondria
> > sp.reduced molecular seawater CO2 concentrations by 73%, which caused
> > photosynthesis and calcification rates to increase (>2-fold) in
> > Acropora and Montipora colonies. By inference, i suggest this would also
> > manifest as increased bleaching resistance - but lets test it.
> > Great, great experiment with loads of details for designing and
> > an upscaled field experiment of a similar ilk. I have the greatest of
> > respect for the research and ideas of Ted.
> > scott
> > https://www.researchgate.net/profile/Scott_Wooldridge
> > cited literature
> > McConnaughey (2000) Community and environmental influences on reef coral
> > calcification. Limnology and Oceanography 45:1667-1671.
> > ---------- Forwarded message ----------
> > From: Scott Wooldridge <swooldri23 at gmail.com>
> > Date: Thu, Aug 24, 2017 at 12:04 PM
> > Subject: How can we "bleach proof" transplanted coral nurseries?
> > To: coral-list at coral.aoml.noaa.gov
> > Dear fellow coral researchers,
> > I have received numerous emails asking to suggest possible ways that we
> > be able to enhance the thermal bleaching resistance of transplanted
> > - if as i suggest, intracellular CO2-limitation of the endosymbiont
> > phyotosynthetic machinery is the underpinning mechanism.
> > Just drawing quickly attention back to the following manuscripts:
> > https://www.researchgate.net/publication/308746785_Excess_
> > seawater_nutrients_enlarged_algal_symbiont_densities_and_
> > bleaching_sensitive_reef_locations_1_Identifying_
> > thresholds_of_concern_for_the_Great_Barrier_Reef_Australia
> > https://www.researchgate.net/publication/317100418_
> > Instability_and_breakdown_of_the_coral-algae_symbiosis_
> > upon_exceedence_of_the_interglacial_pCO2_threshold_
> > 260_ppmv_the_%27%27missing%27%27_Earth-System_feedback_mechanism
> > It is clear, that the biological challenge is to keep endosymbiont
> > (symbiodinium) levels at optimal levels (~1.5 x10^6 cells.cm2 host tissue
> > in branching corals). Two factors in combination promote 'excess'
> > - elevated pCO2 and dissolved inorganic nutrients (principally nitrogen)
> > concentrations.
> > Thus, the bioengineering challenge is also clear. We need to lower pCO2
> > DIN in the immediate vicinity of transplanted corals (or coral reefs in
> > general).
> > In my opinion (and being a pessimist/realist? in my belief that
> > governmental institutions have the political will to reduce pCO2 or DIN
> > runoff to the levels required for a stable coral symbiosis) the only hope
> > we have is to investigate the beneficial role that co-transplanted
> > / macro-algae / crustose coraline algae can play.
> > Active seaweed growth has the potential to draw down both DIN and pCO2 in
> > the seawater in their near vicinity. Note: seaweed precipitate no (or
> > little) CaCo3 (= source of CO2 to seawater)
> > The use of "algal scrubbers" to reduce DIN levels in aquarium systems is
> > common practice. Can we do something similar within our transplanted
> > nurseries and co-locate seaweeds?
> > Obviously, field research is needed here. But a couple of interesting
> > results are noteworthy, and suggest the successful outcomes may be
> > Firstly, in the lab, Yuen et al. (2009) were able to demonstrate that
> > (in this case crustose coralline algae) when co-located with Acorpora
> > digitifera in small tanks were able to quickly (days) draw down DIN (and
> > possibly pCO2?) levels. This resulted in the exact benefits expected if
> > intracellular CO2-limitation is a controlling feature of endosymbiont
> > behaviour. It increased photophysiology efficiency (Fv/Fm, ETR), and
> > reduced the level of bleaching and mortality compared to non treatment.
> > https://www.researchgate.net/publication/319255076_
> > Published_manuscript_Yuen_et_al_2009_Effects_of_live_rock_
> > on_the_reef-building_coral_Acropora_digitifera_cultured_
> > nitrogenous_compounds_Aquacultural_Engineering_4135-43
> > This is a promising result in the lab. But what of any field evidence?
> > There is an interesting dataset by Jompa and McCook (1998) who (quite by
> > accident) recorded much lower levels of bleaching and mortality in corals
> > that were surrounded by seaweed (particurlarly Sargassum spp) during the
> > 1998 mass bleaching event on the inshore Great Barrier Reef. The authors
> > were at the time undertaking another unrelated experiment that involved
> > manually removing seaweed from some reef sites. They observed a dramatic
> > (2-3 fold) increase in the level of coral bleaching at sites from which
> > seaweeds had been removed.
> > https://www.researchgate.net/publication/319255226_The_
> > beneficial_role_of_seaweeds_in_reducing_coral_bleaching_
> > on_the_inshore_reefs_of_the_Great_Barrier_Reef_1998
> > The authors speculated that the seaweed may have been providing a shading
> > benefit (and this may be true). However, could it also have been the case
> > that the seaweed had reduced seawater DIN and pCO2 in the vicinity of the
> > corals? I think we need (with haste) to test this possibility.
> > One issue may be that we need the seaweed to be in an active growing
> > to be of real benefit. For example, in artificial wetlands used to treat
> > nutrient effluent it is well know that nutrient uptake rates into plant
> > biomass are high initially and then tail off. This necessitates (for this
> > system) that the plants be harvested and removed at the end of each
> > season. Luckily for us, seaweeds tend to die back in the winter months
> > naturally and we may not need to worry about this? Anyway, now i am just
> > guessing.
> > I hope this may be of some benefit in sparking the challenge to that
> > eco-engineer/entrepreneur.
> > scott
> > https://www.researchgate.net/profile/Scott_Wooldridge
> > Cited Literature
> > Jompa and McCook (1998) Seeweeds save the reef. Unpublished report.
> > Yuen et al. (2009) Effects of live rock on the reef-building coral
> > digitifera cultured with high levels of nitrogenous compounds.
> > Engineering 41:35-43
> > _______________________________________________
> > Coral-List mailing list
> > Coral-List at coral.aoml.noaa.gov
> > http://coral.aoml.noaa.gov/mailman/listinfo/coral-list
More information about the Coral-List