[Coral-List] Coral reefs in the Gilbert Islands of Kiribati after more than a decade of multiple stressors

Tue Sep 21 16:13:11 UTC 2021

Hi Austin,

Thanks for your kind words about our publication and for sharing your
thoughts and feedback.

One quick clarification: In Abaiang (the less disturbed sites in our
study), there was very little *Acropora *before the Crown-of-Thorns
outbreak. The CoTs outbreak did not drive a decline in *Acropora* in this
case. Instead, *Acropora *cover (and the cover of other branching corals
like *Pocillopora) *in Abaiang declined after bleaching in 2009-2010
(before the start of our study), leaving low-cover coral communities
dominated largely by massive *Porites* and other hardy corals (the classic
'winners' after bleaching events). When the CoTs outbreak happened in
2013-2014, the CoTs fed on the survivors from the bleaching event (mainly,
the massive *Porites*). Again, we found some evidence the reefs in Abaiang
are beginning to recover (albeit slowly) although if/when they recover,
reefs will likely not have much *Acropora*. In Tarawa, disturbed reefs were
more resistant to bleaching in the first place, because prior to bleaching
they were already dominated by a weedy coral species, *Porites rus*, that
is less sensitive to both heat stress and local disturbance (Tarawa's reefs
were also not affected by the 2013-2014 CoTs outbreak).

I am surprised that you perceived our study as putting a positive spin on
an ongoing crisis; I did not consider our findings to be altogether
positive, although they are nuanced. These altered ecosystem states will
come with trade-offs for people who live near and depend on these reefs in
Kiribati, but we're not yet sure how they will manifest. Reefs dominated by
weedy corals like *Porites rus* (like those in Tarawa) may offer less
protection for shorelines than more diverse, high-cover coral communities
(and might be less able to keep up with sea-level rise); reefs in Tarawa
are also vulnerable to 'ecological surprises' given that they are dominated
by a single species, and may host less diverse communities of reef fish
and/or invertebrates. On the other hand, less disturbed reefs in Abaiang may
offer more services for local people in the long run given their higher
relative coral diversity and potential to recover, but they were less
resistant to heat stress in the first place, and recovery may take a long
time. It has been over a decade now since the bleaching event in 2009/2010
and we are just beginning to see relatively small signs of recovery.

The MFMRD has some ongoing coral gardening projects underway and I am sure
they would be open to future opportunities to collaborate so they may
expand upon these efforts. Thank you for the offer to support their
important work, and I look forward to keeping in touch.

Best,
Sara

Sara Cannon, M.Sc. (*she/her/hers*
<https://equity.ubc.ca/resources/gender-diversity/pronouns/>)
PhD Candidate, University of British Columbia
Department of Geography, and the
Institute for Oceans and Fisheries
saracannon.ca
@secanno

*I live and work on the traditional, ancestral, and unceded territory of
the xʷməθkʷəy̓əm <https://www.musqueam.bc.ca/> (Musqueam), sḵwx̱wú7mesh
<https://www.squamish.net/> (Squamish), and sel̓
<https://twnation.ca/>íl̓witulh <https://twnation.ca/> (Tsleil Waututh)
nations. Learn more about territorial acknowledgements and find out whose
land you are on here <https://native-land.ca/territory-acknowledgement/>.*
A reading list on Decolonizing Conservation:
bit.ly/decolonizing-conservation

On Mon, Sep 20, 2021 at 9:35 PM Austin Bowden-Kerby <abowdenkerby at gmail.com>
wrote:

> Dear Sarah,
>
> Thank you so much for this- which I noticed was just published last month-
> Congratulations on a job well done!   Your study is a major contribution to
> what is happening on the leading edge of climate change and predicted
> collapse of coral reefs.  Simon had shared part of this with me already,
> but this is a lot more complete.
>
> "Coral reefs in the Gilbert Islands of Kiribati: Resistance, resilience,
> and recovery after more than a decade of multiple stressors"
>
> I am just digesting this as part of this discussion thread. My initial
> comment, tied to what I have said earlier, is that the title is a bit
> misleading with respect to the seriousness of the situation and what is
> actually happening.  Yes, there are signs of hope, and important to
> report on that, but a more realistic title might have been given,
> especially anticipating that the media or others might use the study to
> downplay the seriousness of what is happening.  Perhaps the title might
> could have been something like this:
>
> "Coral reefs in the Gilbert Islands of Kiribati: Phase shifts, major
> community change, coral species demise and local extinctions after more
> than a decade of recurring thermal stress"
>
> This is the fourth paper where a positive spin is put on what amounts to a
> grave disaster and a vastly altered ecosystem in the dark heart of this
> crisis unfolding in the Central Pacific, and so I wonder what are the
> potential negative impacts of putting any sort of positive spin on what
> should be a loud cry for urgent action by governments, international
> organizations, and coral reef scientists?
>
> To me, the most important findings of your study are that you have picked
> up and substantiated the trends others are observing all over the region,
> with Porites increasing and dominating and Acropora declining.  The fact
> that two very close atolls can have such different outcomes is extremely
> interesting.  Your data also shows another important reality- that COTS and
> snail predation are very much a factor in the inability of Acropora species
> to recover or to adapt to rising temperatures.  Acropora species certainly
> have variants that are similar in their bleaching resistance to Porites. In
> our Fiji sites, we have Acropora genotypes that can survive unbleached to
> 35-37C. But the sad truth is that few of these resistant colonies survive
> for long once most of their kind perish in a mass bleaching, as predator to
> prey ratios increase drastically and the corals are killed out by
> predators, while Porites is not a desired food species in comparison.  So
> in Fiji, we tend to ignore Porites in our adaptation sites, as those
> species are already dominant on hot nearshore reefs, and holding their
> own.  We choose to focus our efforts on finding, sampling, and growing
> multiple bleaching resistant genotypes of each species of  Acropora alive
> in cooler waters and free of predators, by local translocation and by
> predator free nursery methods, plus removal of predators in outplant
> sites.  The objective is to prevent these species from further decline or
> going locally extinct in the coming years, so that they can be restored
> where conditions allow, buying precious time for these corals and the
> diverse fish and invertebrate species which associate with living Acropora
> corals.   As we all know, Porites provides very different habitat.
>
> Once the pandemic is sorted and the Kiribati borders open back up again, I
> plan to return, and if possible poking around more extensively, and with
> more funds than have been available thus far, being able to hire local
> staff to carry out youth focused monitoring and restoration programs under
> supervision.  As such, it would be good if partnerships can be formed to
> work together in such a vast geographic area, with so much potential as a
> learning site of global significance, a possible window into the future for
> all coral reefs.  My particular focus will be very different from the focus
> of others, and I would think that complementary research can occur.   We
> also welcome collaborative research and site visits to our Fiji sites and
> gene bank nurseries in the Mamanuca Islands, after November, when Fiji
> plans to reopens our borders.
>
> Much time has been lost due to this pause, and so once travel becomes
> possible again, we need to to seize the moment.
>
> Kind regards to all,
>
> Austin
>
>
> Austin Bowden-Kerby, PhD
> Corals for Conservation
> Sustainable Environmental Livelihoods for the Future
> P.O. Box 4649 Samabula, Fiji Islands
> https://www.corals4conservation.org
> https://www.facebook.com/C4Conservation
> https://www.bbc.co.uk/programmes/p009j6wb
> <http://www.bbc.co.uk/programmes/p009j6wb>
> TEDx talk https://www.youtube.com/watch?v=7PRLJ8zDm0U
>
> https://www.globalgiving.org/projects/emergency-response-to-massive-coral-bleaching/
> <https://www.globalgiving.org/projects/emergency-response-to-massive-coral-bleaching/>
>
>
> Teitei Livelihoods Centre
> Km 20 Sigatoka Valley Road, Fiji Islands
> (679) 938-6437
> http:/www.
> <http://permacultureglobal.com/projects/1759-sustainable-environmental-livelihoods-farm-Fiji>
> teiteifiji.org
>
> http://permacultureglobal.com/projects/1759-sustainable-environmental-livelihoods-farm-Fiji
> https://www.facebook.com/teiteifarmstay
>
> https://www.globalgiving.org/projects/happy-chickens-for-food-security-and-environment-1/
>
>
>
>
>
> On Mon, Sep 20, 2021 at 11:58 AM Sara Cannon <secanno at gmail.com> wrote:
>
>> Hi all,
>>
>> I am a Ph.D. candidate at the University of British Columbia (advised by
>> Simon Donner), studying coral reef resilience and interactions between
>> local and global stressors facing coral reefs in the central Pacific.
>>
>> Simon and I have a new paper out with our Kiribati Ministry of Fisheries
>> and Marine Resource Development (MFMRD) collaborators in PLoS One that I
>> wanted to share with the list, and that I also think speaks directly to the
>> discussion below. We investigated the trajectory of coral reefs in Tarawa
>> and Abaiang Atolls in the Gilbert Islands from 2012 - 2018, after more than
>> a decade of multiple stressors: https://doi.org/10.1371/
>> journal.pone.0255304
>>
>> Here is a short press release summarizing some of our findings and their
>> implications for management: https://news.ubc.ca/2021/08/
>> <https://news.ubc.ca/2021/08/11/sticky-questions-raised-by-study-on-coral-reefs/>
>> 11/sticky-questions-raised-by-
>> <https://news.ubc.ca/2021/08/11/sticky-questions-raised-by-study-on-coral-reefs/>
>> study-on-coral-reefs/
>>
>> <https://news.ubc.ca/2021/08/11/sticky-questions-raised-by-study-on-coral-reefs/>
>>
>> Simon has worked closely with the MFMRD since before 2010. The government
>> is leading programs to monitor local coral reefs and is also well aware of
>> (and often directly involved in) the work international researchers are
>> doing within its borders, as well as the implications of this research. As
>> you've mentioned, reefs in the Gilberts are unique because they experience
>> more frequent heat stress than reefs in other parts of the Pacific due to
>> their location near the equator. These reefs may provide a preview of what
>> coral reefs elsewhere will look like in the future as the climate continues
>> to warm and heat stress becomes more frequent.
>>
>> Simon and I were scheduled to meet our co-authors in Kiribati in 2020 to
>> repeat our data collection and conduct fish surveys, but unfortunately,
>> were unable to because of COVID. The MFMRD told us that there was no major
>> bleaching observed in the Gilberts after our study period ended in 2018. We
>> also found no evidence of bleaching in 2014 - 2016, when there was a
>> bleaching-level heat stress event in the Gilberts.
>>
>> Reefs in Tarawa, the capital of Kiribati and home to about 65,000 people,
>> were more resistant to the 2004-2005 and 2009-2010 heat stress events than
>> those in neighbouring Abaiang (population ~5,500) where the reefs
>> experienced less local pressure. Reefs in Tarawa have high coral cover but
>> are dominated by a single weedy coral species, *P. rus, *which is
>> resistant to both heat stress and local disturbance*. *By comparison,
>> reefs in Abaiang pre-bleaching were home to more sensitive taxa, and
>> bleaching in 2010-2011 followed by a Crown-of-Thorns outbreak in 2013-2014
>> drove a shift on these reefs to turf algae-dominance. Despite their lower
>> coral cover, coral communities in Abaiang were comparatively more diverse
>> than those in Tarawa in 2018, and we found some signs that they may be in
>> the process of recovering.
>>
>> The shift to *P. rus*-dominated reefs in Tarawa will likely come with
>> trade-offs for local people, although we are not sure exactly how these
>> will manifest. We hope to address some of these questions in future studies.
>>
>> I hope this provides useful context (for this discussion and others)!
>>
>> Best,
>> Sara
>>
>> Sara Cannon, M.Sc. (*she/her/hers*
>> <https://equity.ubc.ca/resources/gender-diversity/pronouns/>)
>> PhD Candidate, University of British Columbia
>> Department of Geography, and the
>> Institute for Oceans and Fisheries
>> saracannon.ca
>> @secanno
>>
>>
>>
>> *I live and work on the traditional, ancestral, and unceded territory of
>> the xʷməθkʷəy̓əm <https://www.musqueam.bc.ca/> (Musqueam), sḵwx̱wú7mesh
>> <https://www.squamish.net/> (Squamish), and sel̓
>> <https://twnation.ca/>íl̓witulh <https://twnation.ca/> (Tsleil Waututh)
>> nations. Learn more about territorial acknowledgements and find out whose
>> land you are on here <https://native-land.ca/territory-acknowledgement/>.*
>> A reading list on Decolonizing Conservation:
>> bit.ly/decolonizing-conservation
>>
>>
>> On Mon, Sep 20, 2021 at 6:17 AM Austin Bowden-Kerby via Coral-List <
>> coral-list at coral.aoml.noaa.gov> wrote:
>>
>>> Dear Michael,
>>>
>>> Thanks for your detailed and thoughtful reply.  Sorry if my letter was
>>> unkind, your paper is indeed excellent and very useful information.  I
>>> absolutely agree with your conclusions in the text and at the end about
>>> the
>>> need to conserve and protect these more adapted coral populations.
>>>
>>> I also was contacted by Nathan Cook regarding not yet published survey
>>> work
>>> (with Adam Smith and others), that shows some good Acropora populations
>>> surviving in the Kanton lagoon, but with very little Acropora surviving
>>> on
>>> the reef front where the corals had not developed thermal tolerance due
>>> to the cooler conditions.  While the continuing presence of Acropora is
>>> reassuring, I consider that this is not only due to bleaching resistance,
>>> it is also due to the less severe intensity of the event when compared to
>>> the islands closer to the equator like Jarvis and Kiritimati Atoll.  If
>>> that hot water pool had hit Kanton directly, most of these corals would
>>> also be dead.
>>>
>>> The reason I posted my concern was that I had just read one of the
>>> several
>>> news stories which have been posted on social media, using your studies
>>> and
>>> others to present an overly optimistic outlook, which I consider to be
>>> out
>>> of touch with the wider reality.  The news reports on this work fail to
>>> mention that the Phoenix islands were not as severely impacted by this
>>> particular heat wave, which severely impacted Jarvis and close to 100% of
>>> its corals were lost (0.3% cover, Brainard et al. 2018), as well as
>>> Kiritimati Atoll, which lost 95% of its corals overall and virtually all
>>> of
>>> its Acropora and Pocillopora corals (Bowden-Kerby, 2021). These press
>>> reports often fail to mention that the bleaching is coming with increased
>>> frequency and force, and that since the 2014-15-16 event, the Gilbert
>>> chain
>>> experienced  two additional severe bleaching events in 2018-2019, and
>>> 2019-2020, and that no systematic assessment of the reefs has been done.
>>>
>>> My biggest concern is that the Government of Kiribati, perhaps in part
>>> due
>>> to the reporting the media has picked up from your report and others,
>>> has
>>> remained unaware of the seriousness of the situation.  Imagine what the
>>> response would be if the reefs Hawaii or Fiji were killed off in a severe
>>> mass bleaching event?  There are no eyes on Kiribati, as it has been five
>>> years with no response.  None of the major international conservation
>>> NGOs
>>> work in Kiribati.  But even simply following the NOAA remote sensing data
>>> should establish that Kiribati's coral reefs are the most impacted from
>>> bleaching temperatures of any coral reefs on earth, and that a disaster
>>> of
>>> huge magnitude has hit beneath the water, but no one seems to have
>>> noticed-
>>> and so there is absolutely no response!   What lessons might be learned
>>> that are now being lost?   Kiribati is the leading edge of the predicted
>>> planetary demise of coral reefs, and therefore the situation warrants a
>>> proper and more intensive monitoring and assessment program.  For now,
>>> the
>>> Phoenix Islands might be the only part of Kiribati that was at least
>>> partially spared, but what will the coming years bring?
>>>
>>> Again, while the evidence of thermal adaptation on Kanton is a valid
>>> reason
>>> for some hope, it is clear from the data that the main body of the hot
>>> pool
>>> never reached Kanton and nearby atolls.  Jarvis and Kiritimati were
>>> immersed in the dark heart of the oceanic hot blob of 2015-16, and very
>>> few
>>> corals of any species survived.  The coral populations of Palmyra to the
>>> North were also on the fringe of the hot blob, and your paper reporting
>>> corals surviving intact there has also been reported in the media as a
>>> cause for hope.  Perhaps it is these moderately stressed coral
>>> populations, where corals can best adapt and become more bleaching
>>> resistant?  But the big question is whether these more adapted coral
>>> populations will in the future be able to survive the intensity of heat
>>> that the region is capable of generating?  There is reason to doubt that
>>> they will, because the most resistant of the corals are located in the
>>> warm
>>> shallows and within the warm lagoons, and it is these same lagoons and
>>> shallows which have the potential to get so hot as to exceed all
>>> possibilities for coral survival.
>>>
>>> The Kiritimati mass die-off of corals has impacted me deeply, and caused
>>> me
>>> to reexamine everything I was doing with coral restoration, and to change
>>> my coral restoration approach.  I kicked myself, and realized: if only we
>>> had come a few years earlier and collected samples of the bleaching
>>> resistant corals from the lagoon, and moved them into a nursery near the
>>> much cooler pass, or transplanted them onto the reef front directly, they
>>> would certainly have survived.   Now I live with the realization that
>>> time
>>> is ticking away for the remaining hot pocket reefs and thermally adapted
>>> coral populations everywhere- including those in Kanton lagoon, are in
>>> grave danger of dying out in the coming years.  This is why we now focus
>>> most of our restoration efforts on moving coral samples from the hottest
>>> parts of the lagoons and nearshore reefs into cooler waters at the passes
>>> and eventually to the reef front, so that some of the most heat adapted
>>> corals stand a good chance of surviving the next massive heat wave.
>>> After
>>> all these are for the most part the exact same species. The corals you
>>> have
>>> recorded for Kanton and the other Phoenix Islands are precious resources
>>> for the future.  If a program to sample multiple genotypes of these
>>> bleaching resistant corals and to transplant them to where the water will
>>> never reach the 35-40C conditions possible at some future date for the
>>> lagoons, they will not only survive, but they may not even bleach at all.
>>> The corals can then also spread their resilience.  But how long do we
>>> have?  When can we begin?
>>>
>>> Lastly, is my perspective on Acropora is as an old timer, living in
>>> Micronesia as a pre-teenage and teenage boy in the 1960s, and visiting
>>> many
>>> islands and atolls in the 1970s and 80s, my recollection is that the reef
>>> front and lagoon populations of just about all atoll reefs are Acropora
>>> dominated- at least they were back then. Tuvalu and Tokelau, the nearest
>>> coral reefs, both remain Acropora dominated.  So to me it seems that
>>> Kanton
>>> and the Phoenix islands must be atypical- already on their trajectory to
>>> alternate steady states?  I suspect that a geological core would show
>>> Acropora dominance up until relatively recent times.  Did a phase shift
>>> happen when no one was watching?  On geological timescales, I don't see
>>> much prospect for non-Acropora reefs keeping up with rising seas and/or
>>> natural subsistence, but of course any coral at all is better than none.
>>>
>>> Thanks for listening,
>>>
>>> Austin
>>>
>>> Austin Bowden-Kerby, PhD
>>> Corals for Conservation
>>> P.O. Box 4649 Samabula, Fiji Islands
>>> https://www.corals4conservation.org
>>> TEDx talk https://www.youtube.com/watch?v=7PRLJ8zDm0U
>>>
>>> https://www.globalgiving.org/projects/emergency-response-to-massive-coral-bleaching/
>>> <
>>> https://www.globalgiving.org/projects/emergency-response-to-massive-coral-bleaching/
>>> >
>>>
>>>
>>> Teitei Livelihoods Centre
>>> Km 20 Sigatoka Valley Road, Fiji Islands
>>> (679) 938-6437
>>> http:/www.
>>> <
>>> http://permacultureglobal.com/projects/1759-sustainable-environmental-livelihoods-farm-Fiji
>>> >
>>> teiteifiji.org
>>>
>>> https://www.globalgiving.org/projects/happy-chickens-for-food-security-and-environment-1/
>>>
>>>
>>>
>>>
>>>
>>> On Thu, Sep 16, 2021 at 7:07 PM Michael Fox via Coral-List <
>>> coral-list at coral.aoml.noaa.gov> wrote:
>>>
>>> > Dear Austin,
>>> >
>>> >
>>> > Thanks for sharing your perspective. However, mid-ocean atoll systems
>>> are
>>> > not all dominated by *Acropora* in their natural state as you are
>>> > suggesting. Indeed, the assumption that they "should be" inevitably
>>> leads
>>> > to incorrect interpretations of ecosystem trajectory.
>>> >
>>> >
>>> > A history of benthic monitoring in the Phoenix Islands extending to the
>>> > late 1960s indicates *Acropora* was not the most dominant coral in at
>>> least
>>> > the last 60 years. Further, while we don't contest that bleaching has
>>> > reduced *Acropora* abundance in the area, these declines are not as
>>> > pervasive as you imply. At specific sites where we know *Acropora* to
>>> have
>>> > been locally dominant, it is recovering, rather than disappearing.
>>> Notably,
>>> > as of 2018 Kanton's lagoon reefs are composed primarily of table and
>>> > staghorn *Acropora*, which have recovered from almost complete
>>> mortality in
>>> > 2002.
>>> >
>>> >
>>> > Kiribati is comprised of 33 islands across three unique archipelagos
>>> that
>>> > span nearly 3.5 million square kilometers of ocean. We think it is
>>> wrong to
>>> > assume that observations from Kiritimati over a narrow window of time
>>> can
>>> > be generalized to the rest of the reefs in Kiribati, some of which have
>>> > withstood and recovered from recurrent heatwaves over centuries.
>>> >
>>> >
>>> > The impact of the 2015-16 heatwave on reefs across the Pacific basin
>>> cannot
>>> > be overstated and is a warning of what we're facing today and in the
>>> > future. However, as the global coral reef community works to forestall
>>> > coral reef extinction, it is important to engage in thoughtful
>>> discussion
>>> > based on facts and accurate natural history. If some sites on coral
>>> reefs
>>> > are managing to keep pace with climate change, like those on Kanton
>>> Island
>>> > in PIPA, lets pay attention, identify the mechanisms by which this
>>> > resilience is conferred, and keep open minds. We have a lot still to
>>> learn.
>>> >
>>> >
>>> > All the best,
>>> >
>>> > Mike
>>> > _______________________________________________
>>> > Coral-List mailing list
>>> > Coral-List at coral.aoml.noaa.gov
>>> > https://coral.aoml.noaa.gov/mailman/listinfo/coral-list
>>> >
>>> _______________________________________________
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>>