[Coral-List] Update from the Maldives + 50 Reefs Initiative

Ove Hoegh-Guldberg oveh at uq.edu.au
Sun Mar 26 00:12:52 EDT 2017

Hi everyone. We have been in the Maldives for the past week with our team from the Institute – surveying our baseline sites again (first assessment was done in 2015) using semi-autonomous vehicles and image recognition. While we are having fun together doing science and interacting with local scientists and people, we have been shocked by the amount of mortality since 2015.  The team will be moving to 25 other sites over the next few weeks where we will do our 2 km transects – hopefully finding reefs in better shape.  We will report back in early April.

On other matters:  We were also pleased to see how much interest the 50 Reefs (50R) Initiative generated among the coral reef community, and understand that many of you had questions and suggestions about the initiative and how it might work. We welcome the support and the feedback, and would like to take the opportunity to explain a bit more about the 50 Reefs initiative.

The approach behind the 50R initiative crystalized for me personally at the COP21 meeting of the UNFCCC in Paris in Dec 2015.  As you know, the Paris conference adopted clear climate change targets in terms of maintaining average global temperatures to well below 2°C, and 1.5°C in the long-term.  Since then, 133 of the 197 Parties to the Convention have ratified it, with the Paris Agreement entering into force on 4 November 2016.  Essentially, the Paris Agreement tells us that the pathway that we must adopt minimises climate change but will still involve a further 0.5°C increase in surface temperature before stabilisation of global climate occurs around mid to late century.

This is good news (despite the near-term impacts) for the long-term survival of human and natural systems.  It minimises change and allows biological and human systems to ‘catch up’ once stabilization has been achieved.  As we know, coral reefs can recover quite rapidly after a disturbance, but will only persist if those disturbances don't increase in frequency and severity. Over longer timescales, coral reef organisms will be able to evolve and expand within these new and stabilised conditions.

The unavoidable downside, however, is that there will be additional impacts over the next 40-50 years prior to stabilisation. One of these impacts will be the continued decline of corals and coral reefs as water temperatures increase by further 0.5oC. Estimates from several modelling groups (e.g. Frieler et al. 2012, DOI: 10.1038/NCLIMATE1674) have come to the conclusion that most of today’s corals will disappear by mid-century stabilisation under a Paris Agreement-like pathway (RCP1.9-2.6). And if one has trouble accepting this conclusion (and those of other studies), then you should only have to look at what has happened to coral reefs over the past 2-3 years in the light of climate change, where warmer than normal ocean temperatures have destroyed huge amounts of coral (the Maldives and Nth GBR being massive cases in point). In many instances, coral mortality once expected over decades in our changing world is now occurring over years.

This brings us to a moment of truth in my opinion.  Given that exceeding the ambitions of the Paris Agreement goals is unlikely, then the new climate reality becomes one in which the world may well lose 80-90% of its corals and hence coral reefs, but will eventually achieve stability by mid-to-late century. This – whether we like it or not - is as good as it gets.

So, where does that leave us? This represents an important opportunity to ensure that a core of coral reefs is protected as much as possible, acting as effective refugia for a wide range of species over the next 50 years, and serving as a source of critical ‘seed stock’ that will be vital for repopulating the rest of the world's coral reefs in the future.  The reefs that persist may either have lower exposure to climate change, or, for many reasons, may be more robust.

This argument leads to an approach to ensure that coral reefs in general remain part of the earth's biological heritage. The first is that, as a heavily impacted community of reef users and researchers, we need to argue strongly, vigorously, and unambiguously for our leaders to achieve the Paris Agreement goals as an urgent global priority.  The second is that we need to develop a global strategy for facilitating the survival of reefs in the context of the unavoidable climate change that will occur over the next 50 years.

If one accepts this, considerable certainty develops around the climate change issue.  For me, someone who has been extremely concerned about climate change since the 1980s, this is one of the first pieces of major optimism that I have had for a long while.  Rather than climate change and coral reefs being a vague but very serious challenge, we know (given success in tackling and rapidly reducing emissions) that conditions will change for 30-40 years before finally stabilising hence giving coral reefs and most other ecosystems a major chance of surviving climate change.

The increased certainty goes like this.  As the climate changes, stresses on reefs will continue to increase, and more corals and coral reefs will die.  But not all coral reefs are equally vulnerable and hence there is an opportunity to enhance reef recovery by reducing impacts of non-climate change stresses (e.g. pollution, over-fishing, physical destruction).

The 50 Reefs strategy attempts to address this global, massive problem by focusing on a manageable aspect that has a large return on investment. The manageable solution is: identifying a set of globally diverse reefs that are least vulnerable to climate change and that have the best chance of survival, and most likely to be able to repopulate other regions, playing a critical role in the long-term recovery of coral reef ecosystems.  This is not to say that there are many other valid reasons (and projects) for preserving coral reefs – which must also be pursued as a priority.

With this in mind, we have appointed a Scientific Steering Group (SSG) which includes some of the leading experts in coral reef science. It is hoped by April that there will be agreement among SSG members on the reef selection criteria, which will then in turn inform the decision optimisation process. Some of you have made some excellent suggestions as to criteria that might be considered in the selection of reef sites. The decision optimisation process (led by the ARC Centre for Excellence in Environmental Decisions at the University of Queensland and involving Hugh Possingham) will result in a list of locations that are representative of a wide range of reef types, characteristics and geographies, and within which detailed site-specific condition assessments and management planning can be targeted in the future.  This prioritized list is likely to be longer than 50 – and there is no reason that many other reefs will join the list over time as success builds on success.

It is important to realise that this is only the first step in a process that might ultimately see a network of collaborating scientists, philanthropists, NGOs, local indigenous groups, businesses, universities, local communities and governments focus on solving problems within an important set of reefs or coral reef locations.  These later steps are not part of the current initial phase.  50R, however, is an inclusive process that we hope will lead to networks and economies of scale when it comes to collaborative problem identification and solution. And if successful, as argued above, there is no reason why such a strategy might not be expanded to include coral reefs further down this prioritised list as time goes on.

In closing, I think it important to point out what the 50R initiative is and what it is not.  50R is not about shifting resources away from other projects or coral reefs or people. It is initiative is intended to be add to the many great examples of the great conservation science and the management of coral reefs being pursued globally. 50R is also not about just saving 10% of the world's coral reefs and damning the rest. It is about optimising the use of the 10-20% of reefs that are likely to survive climate change (to the best extent) to help regenerate the 80-90% that are likely to have been lost by mid-century.

We hope that 50R provides a clear perspective and process which will help us transition toward a century that ends with coral reefs persisting as prominent and vital features of our world.

Ove Hoegh-Guldberg
Chief scientist
50 Reefs Initiative
Global Change Institute
University of Queensland

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