1

People and ecosystems

Understanding of the links between coral reef ecosystems, the goods and services they provide to people, and the wellbeing of human societies.

2

Ecosystem dynamics: past, present and future

Examining the multi-scale dynamics of reefs, from population dynamics to macroevolution

3

Responding to a changing world

Advancing the fundamental understanding of the key processes underpinning reef resilience.

Coral Bleaching

Coral Bleaching

Coral Reef Studies

ARC Centre of Excellence for Coral Reef Studies
James Cook University Townsville
Queensland 4811 Australia

Phone: 61 7 4781 4000
Email: info@coralcoe.org.au

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James Cook University researchers say a new global database will lead to better marine parks by helping to bridge critical gaps in marine conservation planning.

Dr Jorge G. Álvarez-Romero from the ARC Centre of Excellence for Coral Reef Studies (Coral CoE) at JCU led a study that looked at marine conservation planning worldwide.

“For this study, we developed a database to document conservation planning and analysed all marine studies available in the scientific literature. It clearly shows deficiencies in the present system,” he said.

Dr Álvarez-Romero said systematic conservation planning studies, used to determine which areas would be most useful in conserving marine biodiversity, are growing very quickly.

“Despite this, there is no structured or reliable way of finding information on methods, trends and progress. There is little evidence of input from stakeholders. There are important gaps in geographic coverage and not enough work done on the areas most threatened,” he said.

“We know the number and total extent of protected areas will increase significantly during the next few decades. The challenge is making this expansion count in terms of biodiversity conservation,” he said.

JCU’s Distinguished Professor Bob Pressey, Chief Investigator at Coral CoE and co-leader of the study, said researchers from five countries led most studies, with Australia forging the way in global marine conservation planning.

“Australian organisations have contributed significantly to developing methods and tools that are widely used in conservation planning,” he said.

“Despite these advances, the varying quality and detail in documentation of the studies limits opportunities to develop and apply best-practice principles,” said Professor Pressey.

Dr Morena Mills, conservation scientist at Imperial College London and co-leader of The Conservation Planning Database project, said a global database to track development, implementation and impact of conservation planning is urgently needed, along with a closer analysis of the literature, and continuous and comprehensive documentation of conservation planning exercises.

“The new database is a move towards a centralised repository of information of planning exercises and can advance conservation theory and practice,” she said.

Professor Heather Leslie, an international leader in marine conservation science and Director of the University of Maine’s Darling Marine Center, said “With this database in hand, donors and non-government organisations can identify regions and topical areas needing further work, and scientists, practitioners and policy-makers can learn from previous plans.”

“In addition, it gives the scientific community – including peer reviewers – a means of assessing trends in conservation planning methods and applications, so that we can learn from our previous work and shape our new work accordingly,” she said.

The paper “Research advances and gaps in marine planning: towards a global database in systematic conservation planning” is published in this week’s online edition of the journal Biological Conservation (doi:10.1016/j.biocon.2018.06.027), and is available now through JCU ResearchOnline.

For more information, please check out the Conservation Planning Group blog here.

 

Citation: Álvarez-Romero, J. G., et al. (2018) Research advances and gaps in marine planning: towards a global database in systematic conservation planning. Biological Conservation doi:10.1016/j.biocon.2018.06.027 

 

Contact:

Dr Jorge G. Álvarez-Romero (Jorge works at JCU’s Townsville campus)
M: +61 04 1546 5712
P: +61 07 4781 6517
E: jorge.alvarezromero@jcu.edu.au

Dr Morena Mills (Morena is Senior Lecturer in Conservation Science at the Faculty of Natural Sciences, Department of Life Sciences (Silwood Park), Imperial College London, UK)
M: +44 7933 729847
E: m.mills@imperial.ac.uk

Professor Heather Leslie (Heather is Director of the Darling Marine Center & Libra Associate Professor at The University of Maine, Walpole, ME, USA)
M: +001 207 350 2713
P: +001 207 563 8299
E: heather.leslie@maine.edu

An international team of researchers has mapped Nemo’s genome, providing the research community with an invaluable resource to decode the response of fish to environmental changes, including climate change.

In a breakthrough study led by the King Abdullah University of Science and Technology (KAUST) and the ARC Centre of Excellence for Coral Reef Studies (Coral CoE), researchers used high-tech sequencing tools to create one of the most complete genetic maps for the orange clownfish, a common reef inhabitant and star of the Disney movie, Finding Nemo.

“This genome provides an essential blueprint for understanding every aspect of the reef fish’s biology,” said lead author Dr Robert Lehmann of KAUST in Saudi Arabia.

“It contains 26,597 protein coding genes. And like the world’s largest jigsaw puzzle, it took patience and time to assemble.”

The orange clownfish, Amphiprion percula, is not only the most recognized reef fish on Earth, but also one of the most highly studied.

“This species has been central to ground-breaking research in the ecological, environmental and evolutionary aspects of reef fishes,” said co-author Professor Philip Munday of Coral CoE at James Cook University in Australia.

“For example, the clownfish is a model for studying sex change in fishes. It has also helped us understand patterns of larval dispersal in reef fishes and it’s the first fish species for which it was demonstrated that predator avoidance behaviour could be impaired by ocean acidification.”

The team used state-of-the-art technology to sequence the clownfish’s genome. Their genomic and transcriptomic data is now available via the Nemo Genome DB database.

“The clownfish comprises approximately 939 million nucleotides that needed to be fit together,” said co-author Professor Timothy Ravasi of KAUST.

“This is an extremely valuable resource for the research community and will further establish the orange clownfish as an ideal lab subject for genetics and genomic studies.”

“This is one of the most complete fish genomes ever produced,” said co-author Professor David Miller of Coral CoE at James Cook University.

“Using the PacBio single molecule, real-time sequencing technology, enabled us to achieve a polished result.”

The paper “Finding Nemo’s Genes: A chromosome-scale reference assembly of the genome of the organge clownfish, Amhiprion percula” is published today in the journal Molecular Ecology Resources.

Images available here.

 

This research is dedicated to the memory of Dr Sylvain Forêt, a brilliant scientist, co-author, colleague and friend. (Tribute, pg. 10)

 

Citation: Lehmann, R, Lightfoot, D.J., Schunter, C., Mitchell, C.T., Ohyanagi, Mineta, K., Foret, S., Berumen, M.L., Miller, D.J., Aranda, M., Gojobori, T., Munday, P.L., and Ravasi, T. (2018) Finding Nemo’s Genes: A chromosome-scale reference assembly of the genome of the orange clownfish Amphiprion percula. Molecular Ecology Resources

 

CONTACTS

AUSTRALIA

Prof Philip Munday

Coral CoE

P: +61 (0) 0408 714 794, +61 (0)7 4781 5341 (AEST/ GMT +10)

E: philip.munday@jcu.edu.au

 

SAUDI ARABIA

Dr Robert Lehmann

KAUST (AST/ GMT +3)

E: robert.lehman@kaust.edu.sa

 

Prof Timothy Ravasi

KAUST

P: +61 (0) 491333697 (PDT/ GMT -7)

E: timothy.ravasi@kaust.edu.sa

 

FOR MORE INFORMATION

Catherine Naum

Communications Manager

ARC Centre of Excellence for Coral Reef Studies

P: +61 (0) 0428 785 895, +61 (0)7 4781 6067 (AEST/ GMT +10)

E: Catherine.Naum1@jcu.edu.au

 

Michelle Ponto

Communications – Editorial and Global Media Manager

King Abdullah University of Science and Technology

P: +966 (54) 470 1668 (AST/ GMT +3)

E: michelle.ponto@kaust.edu.sa

 

 

 

A team of international marine scientists working with the ARC Centre of Excellence for Coral Reef Studies at The University of Queensland (Coral CoE) has found evidence to suggest the 2016 coral bleaching on the Great Barrier Reef also affected deep reefs.

Although deep reefs are often considered a refuge from thermal anomalies caused by global ocean warming, the new research highlights limitations to this role and argues that both shallow and deep reefs are under threat of mass bleaching events.

Published in the journal Nature Communications, the new study focuses on the 2016 mass bleaching event that caused the death of 30 per cent of shallow-water corals on the Great Barrier Reef.

The study, details how the impacts of this bleaching did lessen over depth, but were still substantial even on the deep reef.

Lead author Dr Pedro Frade from the Center of Marine Sciences, in Portugal, said the scientists were astounded to find bleached coral colonies all the way down to 40 metres.

“It was a shock to see that the impacts extended to these dimly-lit reefs, as we were hoping that their depth may have provided protection from this devastating event,” he said.

The Great Barrier Reef is known to harbor extensive areas of deep coral reefs, however given their depth these reefs are notoriously difficult to study. Using remotely operated vehicles, the team deployed sensors down to 100 metres to characterise how temperature conditions at depth differ from those in the shallow reef.

UQ Global Change Institute Director and Coral CoE’s Deputy Director,  Professor Ove Hoegh-Guldberg said the study had emphasised the unfortunate vulnerability of the Great Barrier Reef.

“We already established that the refuge role of deep reefs is generally restricted by the limited overlap in species with the shallow reef,” he said.

“However, this adds an extra limitation by demonstrating that the deep reefs themselves are also impacted by higher seawater temperatures.”

Co-author and Coral CoE alumnus, Dr Pim Bongaerts from the California Academy of Sciences said that during the bleaching event, upwelling cold-water initially provided cooler conditions on the deep reef.

“However, when this upwelling stopped towards the end of summer, temperatures rose to record-high levels even at depth,” he said.

A team of divers then conducted surveys during the height of bleaching, across several sites on the northern Great Barrier Reef.

They noted that overall, major bleaching and mortality affected almost a quarter of corals at 40 metres, while confirming previous reports of nearly half the corals being severely affected at the shallower depths.

The researchers have now gone on to study how the process of recovery varies between shallow and deep reefs.

Frade PR, Bongaerts P, Englebert N, Rogers A, Gonzalez-Rivero M and Hoegh-Guldberg O. (2018). Deep reefs of the Great Barrier Reef offer limited thermal refuge during mass coral bleaching. Nature Communications, DOI: 10.1038/s41467-018-05741-0 

For more information, please contact:

Dr Pedro Frade
prfrade@ualg.pt

Prof. Ove Hoegh-Guldberg
oveh@uq.edu.au

Dr Pim Bongaerts
pbongaerts@calacademy.org

New research confronts the elephant in the room – the ‘trilemma’ of population growth, economic growth and environmental sustainability – and reveals the vast incompatibility of current models of economic development with environmental sustainability.

Using data collected from across the globe, national economies and natural resource use were closely examined by an international team of scientists using a mathematical model.

The results suggest that as long as our economic system retains its current structure, and if population growth continues, both high- and low-income countries will fail to achieve environmental sustainability.

The study, published today in the Proceedings of the National Academy of Sciences, is led by Professor Graeme Cumming of the ARC Centre of Excellence for Coral Reef Studies at James Cook University.

“There is a pervasive misconception that economic growth and development will eventually lead to environmental sustainability,” said lead author, Prof Cumming.

“While high-income countries may appear to support a more sustainable lifestyle, in practice, they consume more resources per capita than low-income countries.”

“It’s just that their ecological and economic impacts are felt in other places.”

The researchers found that patterns of resource use for both high- and low-income countries reflected predicable environmental outcomes.

High-income countries often rely more on non-extractive industries, such as manufacturing and services, but also consume more per capita and import more raw materials.

In contrast, in low-income countries, populations depend more on extractive industries such as agriculture, logging and mining, but have lower per capita consumption rates and higher population growth.

For example, an estimated 500 million people globally rely on the goods and services provided by healthy coral reef ecosystems. The effects of climate change are already revealing threats to livelihoods and a potential ecological collapse that is beyond intervention.

“Feedbacks between income and population growth are pushing countries farther from sustainability,” said co-author Professor Stephan von Cramon-Taubadel of the University of Göttingen.

“As a society, we need to find ways to make economic development and good standards of living compatible with ecological sustainability. We can use this knowledge to steer economic growth towards win-win outcomes for people and the environment.”

The researchers argue that one key to achieving this is to restructure the economic system, particularly in less wealthy nations where rapid economic growth may lead to significant declines in quality of life.

The paper “Linking economic growth pathways and environmental sustainability by understanding development as alternate social-ecological regimes” is now available here.

Images available here. Please credit as marked.

Cite as: Cumming, G.C., & von Cramon-Taubadel, S. (2018). Linking economic growth pathways and environmental sustainability by understanding development as alternate social-ecological regimes. Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.1807026115

 

Contacts for interviews

AUSTRALIA

Professor Graeme Cumming
ARC Centre of Excellence for Coral Reef Studies at James Cook University
P: +61 7 4781 6072 (AEST/UTC +10)
E: graeme.cumming@jcu.edu.au

 

GERMANY

Professor Stephan von Cramon-Taubadel
University of Göttingen (CEST/UTC +2)
E: scramon@gwdg.de

 

For more information

Catherine Naum
Communications Manager, ARC Centre of Excellence for Coral Reef Studies
P: +61 (0) 7 4781 6067, +61 (0) 428 785 895 (AEST/UTC +10)
E: catherine.naum1@jcu.edu.au

A new study has found that nearly half of fishers from seven countries had witnessed someone poaching in marine protected areas in the past year and most of them did nothing about it.

Dr Brock Bergseth from the ARC Centre of Excellence for Coral Reef Studies at James Cook University led the study. He said poaching is widespread in the world’s marine protected areas, and that fishers have the potential to make or break a marine protected area.

“Enforcement capacities are often limited, so managers are trying to encourage fishers to help out when they see someone breaking the law. But until now, we were uncertain about how fishers respond when they witness poaching.”

The research team surveyed fishers in Kenya, Tanzania, Madagascar, Indonesia, Papua New Guinea, Costa Rica, and Australia.

Fishers told researchers that they typically did one of four things after witnessing poaching: “do nothing,” “confront the poachers,” “report them to authorities,” or, in rare instances, “join the poachers.”

“Unfortunately, the most common response was to ‘do nothing,’” said Dr Bergseth.

Inaction was especially common on Australia’s Great Barrier Reef (GBR).

“Nearly 80 percent of fishers on the GBR did nothing in response to the observed poaching,” said Dr Bergseth. “This means there is a substantial portion of fishers who managers might hope to engage in surveillance and reporting, given the growing concern over the health of the GBR.”

Co-author Dr Georgina Gurney said fishers offered a variety of the reasons for inactivity after witnessing poaching on the GBR.

“GBR fishers said that they did nothing when they saw others poaching mostly because they thought it wasn’t their concern or their responsibility, they were uncertain as to whether it was illegal fishing, or because of obstacles to reporting.”

In all of the other countries in the study, a desire to avoid conflict was the most common reason offered by fishers for inaction after witnessing poaching, said Dr Bergseth.

“This highlights the fact that dealing with poachers is potentially dangerous in some countries – defending environmental rights can be risky, but there are tools to greatly reduce or eliminate the risk.”

“The bad news is that apathy towards poaching in marine protected areas is widespread,” said co-author Dr Michele Barnes, “but the good news is that there are already many tools and programs to encourage citizens to report poaching and other types of crimes. These can be adapted and tailored to encourage fishers to take action against poaching in a responsible way that minimises risk to themselves.”

The research team found that people who agreed with marine protected area rules and who were included in the decision-making processes were more likely to report or confront poachers.

“We know that when fishers are engaged in the management process of marine protected areas they tend to follow the rules more often. Here, we show that empowering fishers can also encourage voluntary enforcement,” said Dr Barnes.

“Encouragingly, many of the fishers who took action did so because they held stewardship beliefs, or saw that poaching personally affected them. These ideas can be further reinforced and leveraged by managers to improve conservation outcomes,” said Dr Gurney.

“The reality is that fish stocks are almost certainly going to be increasingly depleted in the future, to the point where poaching will affect all of us,” said Dr Bergseth.

“Equipping fishers with this knowledge, and the resources to responsibly do something about it, may well be the deciding factor as to whether our kids enjoy the same resources we do,” he said.

The paper “Addressing poaching in marine protected areas through voluntary surveillance and enforcement” is published today in Nature Sustainability.

Images available here.

Citation: Bergseth, B. J., et al. (2018). “Addressing poaching in marine protected areas through voluntary surveillance and enforcement.” Nature Sustainability 1(8): 421-426.

Contacts:

Dr Brock Bergseth
(currently in USA)
+1 (612) 381 7866 (CDT/ UTC -5)
Brock.bergseth@my.jcu.edu.au

Dr Georgina Gurney (Dr Gurney and Dr Barnes work at JCU’s Townsville campus).
0437 462 151
Georgina.gurney@gmail.com

Dr Michele Barnes
0408 677 570
Michele.barnes@jcu.edu.au

For more information:

Ms Catherine Naum
Communications Manager
ARC Centre of Excellence for Coral Reef Studies
P: +61 (0) 0428 785 895, +61 (0)7 4781 6067 (AEST/ UTC – 10)
E: catherine.naum1@jcu.edu.au

The Great Barrier Reef is losing its ability to recover from disturbances, but effective local management could revive its capacity to bounce back.

Scientists at The University of Queensland, ARC Centre of Excellence for Coral Reefs Studies (Coral CoE) and the Australian Institute of Marine Science (AIMS) have found a decline in the ability of Great Barrier Reef Marine Park reefs to recover after bleaching events, outbreaks of crown-of-thorns starfish or cyclones over an 18-year period, from 1992 to 2010, even before the recent back-to-back bleaching in 2016 and 2017.

Dr Juan Ortiz, lead author from the Australian Institute of Marine Sciences and UQ’s School of Biological Sciences, said that during this time, average coral recovery rates showed a six-fold decline across the Great Barrier Reef.

“This is the first time a decline in recovery rate of this magnitude has been identified in coral reefs,” he said.

The decline is driven by a combination of the legacy effect of acute disturbances like coral bleaching and cyclones and the ongoing effect of chronic pressures like poor water quality and climate change.

Professor Peter Mumby of Coral CoE at The University of Queensland, said that this was serious cause for concern, particularly given the accelerating impacts of climate change on reefs, but it is important to stress that not all reefs are failing.

“I believe there is scope for management to help remedy the situation,” he said.

“Our results indicate that coral recovery is sensitive to water quality, and is suppressed for several years following powerful cyclones.

“Some reefs could improve their recovery ability if the quality of the water entering the reef is actively improved.”

Study co-author Dr Nicholas Wolff, from The Nature Conservancy, said that some areas of the reef are faring better than others, but their overall finding was that action needs to be taken.

“While there was variability among regions, the decline in recovery rate was consistent in all coral types included in the study,” he said.

Dr Ortiz said that the frequency of acute disturbances was predicted to increase, making careful management key.

“The future of the Great Barrier Reef is threatened without further local management to reduce chronic disturbances and support recovery, and strong global action to limit the effect of climate change.”

The research, based on long-term monitoring data collected by AIMS on more than 90 reefs across the Great Barrier Reef Marine Park, is published in the journal Science Advances (DOI: 10.1126/sciadv.aar6127).

Media: Dr Juan Ortiz, j.ortiz@uq.edu.au, +61 (0)412 200 831; Professor Peter Mumby, p.j.mumby@uq.edu.au, +61 (0)449 811 589 (email-preferred); Dr Nicholas Wolff, nicholas.wolff@TNC.ORG; +1 2075226101; Dominic Jarvis, dominic.jarvis@uq.edu.au, +61 413 334 924; Catherine Naum, catherine.naum1@jcu.edu.au, +61 428 785 895.

Note to Editor:

Prof Mumby will be speaking at the Coral Reef Futures Symposium of the Australian Research Council Centre of Excellence for Coral Reef Studies at 1.50pm on 19 July 2018 (AEST). Media are welcome to attend. Follow us on Twitter #CORAL18

Rat control should be considered an urgent conservation priority on many remote tropical islands to protect vulnerable coral reefs, according to an international team of scientists.

New research has confirmed that invasive rats decimate seabird populations, with previously unrecognised consequences for the extensive coral reefs that encircle and protect these islands.

Invasive predators such as rats – which feed on bird eggs, chicks, and even adults birds – are estimated to have decimated seabird populations within 90% of the world’s temperate and tropical island groups, but until now the extent of their impact on surrounding coral reefs wasn’t known.

The new study, led by researchers at Lancaster University (UK), ARC Centre of Excellence for Coral Reef Studies (Coral CoE) at James Cook University and Dalhousie University (Canada), examined tropical ecosystems in the northern atolls of the Chagos Archipelago to uncover how rats have impacted surrounding reefs.

Lead author Professor Nick Graham of Lancaster University, said: “Seabirds are crucial to these kinds of islands because they are able to fly to highly productive areas of open ocean to feed. They then return to their island homes where they roost and breed, depositing guano – or bird droppings – on the soil.  This guano is rich in the nutrients, nitrogen and phosphorus.  Until now, we didn’t know to what extent this made a difference to adjacent coral reefs.”

An extraordinary set of remote tropical islands in the central Indian Ocean, the Chagos islands provided a perfect ‘laboratory’ setting as some of the islands are rat-free, while others are infested with black rats – thought to have been introduced in the late 1700s and early 1800s. This unusual context enabled the researchers to undertake a unique, large-scale study directly comparing the reef ecosystems around these two types of islands.

By examining soil samples, algae, and counting fish numbers close to the six rat-free and six rat-infested islands, scientists uncovered evidence of severe ecological harm caused by the rats, which extended way beyond the islands and into the sea.

Rat-free islands had significantly more seabird life and nitrogen in their soils, and this increased nitrogen made its way into the sea, benefiting macroalgae, filter-feeding sponges, turf algae, and fish on adjacent coral reefs.

Fish life adjacent to rat-free islands was far more abundant with the mass of fish estimated to be 50% greater.

The team also found that grazing of algae – an important function where fish consume algae and dead coral, providing a stable base for new coral growth – was 3.2 times higher adjacent to rat free islands.

“These results not only show the dramatic effect that rats can have on the composition of biological communities, but also on the way these vulnerable ecosystems function (or operate),” said co-author Dr Andrew Hoey from Coral CoE at James Cook University.

“Critically, reductions in two key ecosystem functions (grazing and bioerosion) will likely compromise the ability of these reefs to recover from future disturbances.”

Professor Graham said: “The results of this study are clear. Rat eradication should be a high conservation priority on oceanic islands. Getting rid of the rats would be likely to benefit terrestrial ecosystems and enhance coral reef productivity and functioning by restoring seabird derived nutrient subsidies from large areas of ocean. It could tip the balance for the future survival of these reefs and their ecosystems.”

Associate Professor Aaron MacNeil from Dalhousie University said: “These results show how conservation can sometimes be a bloody business, where doing right by the ecosystem means there is a time to kill. For these invasive rats, that time is now.”

The paper “Seabirds enhance coral reef productivity and functioning in the absence of invasive rats,” is published in the prestigious journal Nature.

The research was led by  Lancaster University (UK) with the ARC Centre of Excellence for Coral Reef Studies (Australia), Dalhousie University (Canada), Department of Biodiversity, Conservation and Attractions, Perth, Australia, University of Western Australia, Australia, Zoological Society of London, UK, University of Exeter, UK, and the International Council for the Exploration of the Sea, Denmark.

 

Note to Editors

Additional key points from the study:

Citation: Graham, N.A.J., Wilson, S.K., Carr, P., Hoey, A.S., Jennings, S., MacNeil, M.A. (2018), Seabirds enhance coral reef productivity and functioning in the absence of invasive rats. Nature https://www.nature.com/articles/s41586-018-0202-3

Link to video and images here. Please credit as marked.

Contacts for interviews

Prof Nick Graham
Lancaster University, Lancaster Environment Centre
Lancaster, U.K.
P: +44 (0) 7479 438 914 (GMT/UTC)
E: nick.graham@lancaster.ac.uk

Dr Andrew Hoey
ARC Centre of Excellence for Coral Reef Studies at James Cook University
Townsville, QLD AUSTRALIA
P: +61 7 4781 5979 (AEST/UTC +10)
E: andrew.hoey1@jcu.edu.au

A/Prof Aaron MacNeil
Dalhousie University, Department of Biology
Halifax, NS, CANADA
P: +1 902 402-1273 (ADT/UTC -3)
E: a.macneil@dal.ca

For further information

Beth Broomby (U.K.)
Head of Press Office, Lancaster University
P: +44 (0) 1524 593719, +44 (0) 7881 813 831 (GMT/UTC)
El: b.broomby@lancaster.ac.uk

Catherine Naum (AUSTRALIA)
Communications Manager, ARC Centre of Excellence for Coral Reef Studies
P: +61 (0) 7 4781 6067, +61 (0) 428 785 895 (AEST/UTC +10)
E: catherine.naum1@jcu.edu.au

Niecole Comeau (CANADA)
Communications, Faculty of Science, Dalhousie University
P: +1 (902) 494-8443, +1 (902) 223-2446 (ADT/UCT -3)
E: niecole.comeau@dal.ca

Tropical oceans teem with the dazzle and flash of colourful reef fishes, and contain far more species than the cold ocean waters found at high latitudes. This “latitudinal diversity gradient” is one of the most famous patterns in biology, and scientists have puzzled over its causes for more than 200 years.

A common explanation for the gradient is that warm reef environments serve as evolutionary hot spots for species formation. But a new study led by researchers at University of Michigan and the Australian Research Council Centre of Excellence for Coral Reef Studies (Coral CoE), has analyzed the evolutionary relationships between more than 30,000 fish species and found that the fastest rates of species formation have occurred at the highest latitudes and in the coldest ocean waters.

Over the past several million years, cool-water and polar ocean fishes formed new species twice as fast as the average species of tropical fish, according to the new study, published today in the prestigious journal Nature.

“These findings are both surprising and paradoxical,” said University of Michigan evolutionary biologist Daniel Rabosky, lead author of the study.

“We find that speciation is actually fastest in the geographic regions with the lowest species richness,” he said.

“Our research certainly paints coral reef diversity in a new light,” said co-author Dr Peter Cowman of Coral CoE at James Cook University, formerly of Yale University (USA).

The authors admit they cannot fully explain their results, which are incompatible with the idea that the tropics serve as an evolutionary cradle for marine fish diversity.

Common sense suggests that a high rate of new species formation will eventually lead to impressive levels of biodiversity. But that depends on how many of the newly formed species survive and how many go extinct.

“Extinction is the missing piece of this puzzle, but it’s the most difficult thing to understand,” Rabosky explained. “We’re now using both fossils and new statistical tools to try to get a handle on what extinction might have been doing in both the polar regions and the tropics.”

The researchers tested the widely held assumption that species-formation rates are fastest in the tropics by examining the relationship between latitude, species richness and the rate of new species formation among marine fishes. They assembled a time-calibrated ‘evolutionary tree*’ of all 31,526 ray-finned fish species, then focused their analysis on marine species worldwide.

Surprisingly, some of the fastest rates of new species formation occurred in Antarctic icefish and their relatives. Other temperate and polar groups with exceptionally high speciation rates include snailfish, eelpouts and rockfish.

Three of the largest coral reef-associated fish groups – wrasses, damselfish and gobies – showed low to moderate rates of species formation. “The fact that coral reefs support many more fish species than polar regions despite these lower rates may have a lot to do with their long history of connectivity and ability to act as refugia,” Cowman said.

“Who would have thought that you’d have these really explosive rates of species formation happening in the coldest Antarctic waters, where water is literally at the freezing point and fish, like the icefish, have to have all kinds of really crazy adaptations to live there, like special antifreeze proteins in their blood to keep it from freezing,” Rabosky said.

The paper “An inverse latitudinal gradient in speciation rate for marine fishes” is now available here.

Images here.

CONTACTS:

USA: Jim Erickson, +1734-647-1842, ericksn@umich.edu

AUSTRALIA: Catherine Naum, +61 428 785 895, catherine.naum1@jcu.edu.au

EDITOR NOTES

* Genetic data were available for more than one-third of the fish species analyzed in the study, and the evolutionary tree was time-calibrated using a database of 139 fossil taxa.

* An evolutionary tree, also known as a phylogenetic tree, is a branching diagram showing the inferred evolutionary relationships among various species. The tree assembled for this project is one of the largest time-calibrated phylogenetic trees ever assembled for any group of animals.

* The authors of the Nature paper, in addition to Rabosky and Cowman, are U-M’s Jonathan Chang, Pascal O. Title and Matt Friedman; Michael Alfaro of the University of California, Los Angeles; Lauren Sallan of the University of Pennsylvania; Kristin Kaschner of the University of Freiburg; Cristina Garilao of GEOMAR Helmholtz Centre for Ocean Research; Thomas J. Near of Yale University; and Marta Coll of the Institute of Marine Science in Barcelona, Spain.

* The work was supported in part by grants from the National Science Foundation and by the David and Lucile Packard Foundation.

The exemplary research of Distinguished Professor Terry Hughes, coral reef scientist and Director of the Australian Research Council Centre of Excellence for Coral Reef Studies, was honoured this week by the Prince Albert II of Monaco Foundation.

At a prestigious ceremony held at the Grimaldi Forum in Monaco, H.S.H. Prince Albert II of Monaco presented Professor Hughes with the 2018 Climate Change Award, recognising his contribution to advancing understanding of the influence of rapid climate change on the world’s coral reefs.

“I wanted to create these Awards in order to offer all my support to the exceptional men and women who have made a commitment to saving our planet,” said H.S.H. Prince Albert II of Monaco.

Professor Hughes is internationally renowned for his outstanding research leadership in the field of coral reef ecology and his work to raise the profile of coral reefs and their vulnerability to unchecked climate change.

In 2016, Professor Hughes convened the National Coral Reef Taskforce to coordinate Australia’s response during the global mass coral bleaching event.

Later that year, Professor Hughes was recognised by Nature magazine as one of Nature’s “Top Ten People Who Mattered This Year” for his leadership in responding to this unprecedented event.  Nature dubbed him “Reef Sentinel,” for the global role he plays in applying multi-disciplinary science to securing reef sustainability.

“Professor Terry Hughes is a highly decorated and well respected scientist—an esteemed Australian Laureate Fellow who has provided important leadership as Director of the Australian Research Council Centre of Excellence for Coral Reef Studies,” said Australian Research Council CEO, Professor Sue Thomas.

“On behalf of the Australian Research Council, I commend Professor Hughes on achieving this international recognition, which recognises his ongoing efforts and contribution to advancing reef science research.”

Professor Terry Hughes said he was delighted to receive the award.

“I am deeply grateful to Prince Albert and the Foundation for honouring me in this way, and I would like to acknowledge the important contribution by many, many colleagues around the world.”

Professor Hughes is one of the world’s most highly cited coral reef scientists.  He is a Fellow of the Australian Academy of Science, and a recipient of the International Society for Reef Studies’ Darwin Medal and an Einstein Professorship from the Chinese Academy of Sciences.

The Foundation’s awards ceremony has taken place every year since 2008 to honour key international figures and organisations who have made an exceptional commitment to safeguarding the planet. Recognition is given for exceptional contributions to one of three priority fields of activity, including climate change. Previous recipients of the Prince Albert II of Monaco Foundation Awards include Dr Jane Goodall, Prof David Suzuki and Sir David Attenborough.

Images here.

CONTACT

Ms Catherine Naum
Communications Manager, ARC Centre of Excellence for Coral Reef Studies
P: +61 (0) 0428 785 895, +61 (0)7 4781 6067 (AEST)
E: Catherine.Naum1@jcu.edu.au

 

A massive study of nearly 1800 tropical coral reefs around the world has found that marine reserves near heavily populated areas struggle to do their job – but are a vast improvement over having no protection at all.

Professor Josh Cinner from the ARC Centre of Excellence for Coral Reef Studies at James Cook University led a team of 37 scientists examining the effectiveness of different reef conservation strategies.

“Fish stocks were extremely depleted on reefs that were accessible to large human populations. Compared to marine reserves far from these human pressures, reserves near high human pressure had only a quarter of the fish and were a hundred times less likely to have top predators such as sharks,” said Professor Cinner.

The scientists also studied how differences in ecological conditions between marine reserves, where fishing is prohibited, and places open to fishing changed as human pressures increased. “This tells you where you can get the biggest impact from implementing conservation,” said Professor Cinner.

“A really novel and exciting part of our study found that the greatest difference in fish biomass between marine reserves and places open to fishing was in locations with medium to high human pressure. This means that, for most fisheries species, marine reserves have the biggest bang where human pressures are medium to high,” he said.

For example, on reefs subject to high human pressure, marine reserves had five times more fish than openly fished reefs – a benefit that can spillover into the depleted fisheries in surrounding areas.

“However, top predators such as sharks were a different kettle of fish,” said co-author Dr Aaron MacNeil from Dalhousie University.

The scientists encountered top predators on less than 30% of their surveys conducted all across the globe, and very rarely in locations where human pressures were high.

“You’d have to do about 200 dives to see a top predator in reserves with the highest human pressure. But where human pressure was low, you’d be likely to see predators more than half the time,” said Dr MacNeil.

Dr Michele Barnes from the ARC Centre of Excellence for Coral Reef Studies at JCU said that in many places, social, economic, and cultural realities mean that marine reserves that entirely prohibit fishing are not an option.

“So, we also looked at how effective other forms of reef conservation were, such as restricting the types of fishing gear that people use. Our results were promising – these restrictions certainly had better outcomes than doing nothing, but not as good as marine reserves. They were a sort of compromise,” she said.

Professor Cinner said the study makes clear the benefits and limitations of implementing key coral reef conservation strategies in different types of locations. “Our research shows where managers will be able to maximise certain goals, such as sustaining top predators or improving the biomass of key fisheries species, and likewise, where they will be wasting their time,” he said.

Paper: here.

Video: here.

 

Contacts:                  

Professor Josh Cinner, CoralCoE at JCU

Mobile +61 417714138 (AEST/UTC +10)

Email: joshua.cinner@jcu.edu.au

 

Dr Michele Barnes, CoralCoE at JCU

Mobile: +61 (0)408677570 (AEST/UTC +10)

Email: michele.barnes@jcu.edu.au

 

Dr Aaron MacNeil, Dalhousie University

Office: +1 (902) 402-1273 (ADT/UTC -3)

Email: a.macneil@Dal.Ca

 

For More Information:

Catherine Naum

Communications Manager, ARC Centre of Excellence for Coral Reef Studies

Office: +61 (0)7 4781 6067 (AEST/UTC +10)

Mobile: +61 (0) 428 785 895

 

Background

The researchers evaluated fish biomass and the presence of top predators on coral reef sites across 41 countries, states, and territories. They used a new way of measuring the human pressures, such as fishing and pollution, to study the effects these are having on fish on the world’s reefs. They developed a ‘human gravity’ scale that calculates factors such as human population size, distance to reefs, and the transport infrastructure on land – which can determine reefs’ accessibility to fishermen and markets.

 

Many coral reefs will be unable to keep growing fast enough to keep up with rising sea levels, leaving tropical coastlines and low-lying islands exposed to increased erosion and flooding risk, new research suggests.

An international team, led by scientists from University of Exeter, Royal Netherlands Institute for Sea Research, Lancaster University and the Australian Research Council’s Centre of Excellence for Coral Reef Studies (Coral CoE), compared the maximum upward growth rates of coral reefs with predicted rates of sea-level rise, and found many reefs will be unable to keep pace.

The growth of coral reefs is strongly influenced by the amount and types of coral living on the reef surface. This growth is now being hampered by combinations of coral disease, deteriorating water quality and fishing pressure, along with severe impacts from “coral bleaching” caused by climate change.

“For many reefs across the Caribbean and Indian Ocean regions, where the study focused, rates of growth are slowing due to coral reef degradation,” said lead author Professor Chris Perry, of the University of Exeter.

“Meanwhile, rates of sea-level rise are increasing – and our results suggest reefs will be unable to keep up. As a result, water depths above most reefs will increase rapidly through this century.”

“Even under modest climate change prediction scenarios (RCP4.5) only about 3% of Indian Ocean reefs will be able to track local sea-level rise projections without sustained ecological recovery, whilst under continued high emission scenarios (RCP8.5) most reefs will experience water depth increases in excess of half a metre,” added co-author Dr Aimée Slangen of NIOZ, Royal Netherlands Institute for Sea Research.

“This is now of critical concern because reefs play a key role as natural sea defences by limiting coastal wave energy exposure,” commented Professor Nick Graham, of Lancaster University, another co-author of the study.

“Efforts to tackle climate change must therefore be coupled with careful management of fishing and water quality protection to prevent widespread submergence through this century.”

The researchers calculated growth rates for more than 200 tropical western Atlantic and Indian Ocean reefs.

“Now more than ever, we must limit global greenhouse gas emissions. Our predictions, even under the best case scenarios, suggest that by 2100 the inundation of reefs will expose coastal communities to significant threats of shoreline change,” said co-author Professor Peter Mumby of Coral CoE at The University of Queensland. “Healthier coral reefs will reduce the rate of seawater inundation.”

Professor Perry concluded: “The most worrying end-point scenario in this respect is that if predictions of increasing bleaching frequency are realised, many reefs may become locked into permanent low growth rate states, leading to more submergence under all future sea-level rise scenarios.”

The paper, published in the journal Nature, is entitled: “Loss of coral reef growth capacity to track sea-level rise under climate change.”

Citation: Perry, Chris T., Alvarez-Filip, Lorenzo, Graham, Nicholas A. J., Mumby, Peter J.,..Macdonald, Chancey et al. (2018). Loss of coral reef growth capacity to track future increases in sea level Nature, 1476-4687 DOI – 10.1038/s41586-018-0194-z

Videos and images available here. Please credit all files to: Prof Chris Perry, University of Exeter, as indicated in the captions document.

Contacts for interviews:

Professor Nicholas Graham
Lancaster University, Lancaster Environment Centre
P: +44 (0) 7479 438 914 (GMT/UTC)
E: nick.graham@lancaster.ac.uk

Professor Peter Mumby
The University of Queensland
P: +61 7 3365 1686 or 0449811588 (AEST/UTC +10)
Email: p.j.mumby@uq.edu.au

For more information:

University of Exeter
Press Office
+44 (0)1392 724828
pressoffice@exeter.ac.uk

Catherine Naum
Communications Manager, ARC Centre of Excellence for Coral Reef Studies
Townsville, QLD AUSTRALIA
P: +61 (0)7 4781 6067 or +61 (0) 428 785 895 (AEST/UTC +10)
E: catherine.naum1@jcu.edu.au

 

A two-year study has found the amount of algae on a coral reef is influenced by interaction between light and temperature, as well as by human impacts. 

Global studies have long linked human activities to an increase in algae and the decline in reef-building corals, but have not focused on the impact of natural changes in the environment.

A team of scientists from the ARC Centre of Excellence for Coral Reef Studies (CoralCoE) and Global Change Institute (GCI) based at The University of Queensland (UQ) have tracked environmental conditions, reef composition and coral-algal competition across Heron Island, on the southern end of the Great Barrier Reef.

They discovered interactions between light and temperature also influenced algal levels.

Lead author and CoralCoE PhD candidate, Kristen Brown said changes in algal biomass influenced the composition and frequency of coral-algal interactions.

Until now, how environmental factors interact to control the abundance of algae have mostly been inferred from seasonal peaks.

“Competition between coral and algae can lead to reductions in coral growth and survival, which can have implications on the structure and function of coral reef ecosystems,” Ms Brown said.

“Algae and their interactions with corals are more relevant than ever, especially given the rapidly degrading coral reef ecosystem dynamics.”

CoralCoE’s Deputy Director, Professor Ove Hoegh-Guldberg said a greater understanding of seasonal and spatial variation was important for interpreting the response of coral reef communities to any future disturbances.

The research,  The dynamics of coral-algal interactions in space and time on the southern Great Barrier Reef’, is published in Frontiers in Marine Science (doi: 10.3389/fmars.2018.00181).

Citation: Kristen T. Brown, Dorothea Bender-Champ, Andreas Kubicek, Rene van der Zande, Michelle Achlatis, Ove Hoegh-Guldberg and Sophie G. Dove (2018). The Dynamics of Coral-Algal Interactions in Space and Time on the Southern Great Barrier Reef. Front. Mar. Sci., doi.org/10.3389/fmars.2018.00181

Media: Kristen Brown, @imkristenbrown, +61 7 3346 7330; 0438 285 283

Corals growing in high-latitude reefs in Western Australia can regulate their internal chemistry to promote growth under cooler temperatures, according to new research at the ARC Centre of Excellence for Coral Reef Studies at The University of Western Australia.

The study, published today in Proceedings of the Royal Society B, suggests that ocean warming may not necessarily promote faster rates of calcification of corals on sub-tropical reefs where temperatures are currently cool (lower than 18C).

Lead author Claire Ross said the study was carried out over two years in Western Australia’s Bremer Bay, 515km south-east of Perth in the Great Southern region. Bremer Bay is a renowned diving, snorkelling and tourism hot spot due to its stunning crystal clear waters, white sand and high marine biodiversity.

“For two years we used cutting-edge geochemical techniques to link the internal chemistry of the coral with how fast the corals were growing in a high-latitude reef,” Ms Ross said.

“These high-latitude reefs (above 28 degrees north and below 28 degrees south) have less light and lower temperatures compared to the tropics, and essentially they provide natural laboratories for investigating the limits for coral growth.”

Ms Ross said the researchers expected the corals to grow slower during winter because the water was colder and light levels lower but they were surprised to find the opposite pattern.

“We were able to link the remarkable capacity for cold-water corals to maintain high growth during winter to the regulation of their internal chemistry,” she said.

“We also found that there was more food in the water for corals during winter compared to summer, indicating that (in addition to internal chemical regulation) corals may feed more to sustain growth.”

Coral reefs are one of world’s most valuable natural resources, providing a habitat for many ocean species, shoreline protection from waves and storms, as well as being economically important for tourism and fisheries.

However, the capacity for corals to build their skeletons is under threat due to CO2-driven climate change. The effects of climate change on coral reefs are likely to vary geographically, but relatively little is known about the growth rates of reefs outside of the tropics.

“Our study is unique because it is among the first to fully decipher the corals’ internal chemistry,” Ms Ross said. “The findings of this study help better understand and predict the future of high-latitude coral reefs under CO2-driven climate change.”

Images and video available here

Citation: Claire L. Ross, Verena Schoepf, Thomas M. DeCarlo, Malcolm T. McCulloch (2018). Mechanisms and seasonal drivers of calcification in the temperate coral Turbinaria reniformis at its latitudinal limits. Proceedings of the Royal Society B. Volume 285 (1879). DOI: 10.1098/rspb.2018.0215

MEDIA REFERENCE

Claire Ross
ARC Centre of Excellence for Coral Reef Studies, UWA School of Earth Sciences
(+61 4) 32 272 636

David Stacey
UWA Media and Public Relations Manager
(+61 8) 6488 3229 / (+61 4) 32 637 716

Catherine Naum
Communications Mgr, ARC Centre of Excellence for Coral Reef Studies
(+61 7) 4781 6067/ (+61 4) 28785 895

Reports in recent years that marine protected areas (MPAs) aren’t effective in saving coral reefs from the damaging effects of global climate change have led some to argue that such expensive interventions are futile. But a study that spanned 700 kilometers of the eastern Caribbean reveals that MPAs can, indeed, help coral reefs.

An international team of scientists from the University of Maine, USA (UMaine) and the ARC Centre of Excellence for Coral Reef Studies at The University of Queensland, Australia (Coral CoE) conducted research on the leeward islands of the Caribbean and discovered that local reef protection efforts can work — contradicting several previous studies.

Local fisheries management resulted in a 62 percent increase in the density of young corals, which improves the ecosystem’s ability to recover from major impacts like hurricanes and coral bleaching, according to the team’s findings, published in Science Advances, a journal of the American Association for the Advancement of Science.

“MPAs can help coral reefs, but studies to the contrary just weren’t measuring the right things at the right scales,” says lead author and Professor of Marine Biology, Bob Steneck, of UMaine.

“The idea behind MPAs is that, by reducing fishing pressure, you increase the number of seaweed-eating fish, and they decrease the amount of harmful seaweed, which makes it easier for baby corals to get started and thrive on the reef. But coral reefs are complicated, and lots of other things can affect fish numbers, their ability to control the growth of algae and the ability of corals to take advantage of this.”

“Taking field measurements on coral reefs is time consuming, so many researchers are forced to take shortcuts and use simple, widely available data to analyse how reefs respond to protection,” says study co-author Professor Peter Mumby of Coral CoE.

“While it sounds obvious, we show that our ability to detect the benefits of MPAs on corals improves dramatically when you take more detailed measurements,” Prof Mumby says.

“For example, a simple option is to count the number of herbivorous fishes. But if, instead, you estimate how intensively these fishes feed, you obtain a much clearer and compelling insight.”

There is no management panacea for any ecosystem, and especially not for coral reefs, Prof Steneck notes.

“Certainly, stresses on coral reefs from climate and atmospheric changes are serious and beyond direct management control. However, we suggest that local management measures can bolster the recovery of corals after damaging events and, eventually, improve their overall condition.”

Doug Rasher of Bigelow Laboratory for Ocean Science in East Boothbay, Maine, adds: “What we show is that relatively small changes can nudge this ecosystem toward one that can maintain and sustain itself.”

The research team, which also included researchers from James Cook University (Australia) and RARE (USA), concludes that the best way to measure the effectiveness of reef conservation is by using a suite of metrics, including the number of fish, amount of seaweed and the number of baby corals, rather than just one indicator of reef health.

This research was partially funded by the National Geographic Society.

Multimedia resources available here.

Video abstract courtesy of University of Maine here.

Citation: Steneck, R.S., Mumby, P.J., MacDonald, C., Rasher, D.B., Stoyle, G. (2018) Attenuating effects of ecosystem management on coral reefs. Science Advances Vol. 4, no. 5,
doi: 10.1126/sciadv.aao5493

 

Contact:

Robert Steneck, steneck@maine.edu (EST)

Peter Mumby, p.j.mumby@uq.edu.au (AEST)

 

For More Information:

Margaret Nagle, nagle@maine.edu (EST)

Catherine Naum, catherine.naum1@jcu.edu.au (AEST)

Jan King, j.king@uq.edu.au (AEST)

Scientists from the ARC Centre of Excellence for Coral Reef Studies (Coral CoE) at The University of Western Australia (UWA) have found that some corals are able to combat the effects of ocean acidification by controlling their own chemistry.

Coral reefs play an important role in protecting coastlines from damage caused by waves and storms, but also provide habitat and shelter for many marine organisms. However, major environmental challenges such as climate change, threaten the survival of coral reefs worldwide.

The world-first study is a breakthrough for marine science because the scientists have identified marine species that are resilient to ocean changes, which will help better understand how to protect coral reefs in the future.

Lead author Dr Thomas DeCarlo said rising carbon dioxide (CO2) levels in the atmosphere were reflected in the ocean, which leads to ocean acidification.

“Acidification hampers the ability of the coral to form skeletons and shells which are the building blocks of reefs,” Dr DeCarlo said.

“In the past few decades, hundreds of experiments have shown that corals have a highly diverse response to ocean acidification depending on the species. However, the reasons why some are more tolerant than others are not clearly understood.

Dr DeCarlo and his team developed a new method to understand the internal chemistry of corals by using specialised equipment that measures the characteristics of the molecules in coral.

“The method showed corals with the most resistance are tolerant because of the way they are able to regulate their calcium levels,” Dr DeCarlo said. “This technique means scientists can identify species that are relatively resistant to ocean acidification.”

“However, we are also looking at the costs associated with resisting acidification, which may potentially make acidification-resistant corals more vulnerable to other stressors.”

Co-author Professor Malcolm McCulloch said previous studies found that even the more hardy coral species lose their ability to adapt to ocean acidification when they bleach under extreme heat events, as experienced in 2016.

“When a coral bleaches, it expels its ‘powerhouse’ – zooxanthellae symbionts, and loses the energy needed to keep its internal mechanisms running,” he said. ”The longer corals stay bleached, the less likely they are to recover.”

The paper, Coral resistance to ocean acidification linked to increased calcium at the site of calcification is published in Proceedings of the Royal Society B

Citation: DeCarlo, T.M., Comeau, S., Cornwall, C.E., and McCulloch, M.T. (2018), Coral resistance to ocean acidification linked to increased calcium at the site of calcification. Proc. R. Soc. B 20180564. DOI: http://dx.doi.org/10.1098/rspb.2018.0564

Images available here.

MEDIA REFERENCE

Thomas DeCarlo (UWA Research Fellow) (+61 4) 09 895 484 (AWST)

Catherine Naum (CoralCoE Communications Mgr) (+61 4) 28 785 895 / (+61 7) 4781 6067 (AEST)

Jess Reid (UWA Media and PR Advisor)     (+61 8) 6488 6876 (AWST)

Thanks to mom and dad, baby reef fish may have what it takes to adjust to hotter oceans.

In a rapidly changing climate, the decline of animal populations is a very real concern. Today, an international team of researchers report new evidence of reef fish adjusting to global warming conditions at the genetic level.

For the first time, researchers from the ARC Centre of Excellence for Coral Reef Studies (Coral CoE) and the King Abdullah University of Science & Technology (KAUST), have found that reef fish can inherit from their parents the genetic tools to adjust to ocean warming.

“When parents are exposed to an increase in water temperature, we found that their offspring improved their performance in these otherwise stressful conditions by selectively modifying their epigenome,” said senior author Prof Philip Munday of Coral CoE at James Cook University.

Epigenetic change refers to chemical modifications in the DNA that signals genes to be switched on or off. A range of factors, including disease, famine, or in the case of this research, heat stress, can stimulate these subtle changes.

In this study, when both parent and offspring experienced the same elevated water temperatures, responsive changes in their epigenome, via selective DNA methylation, were observed that enhanced the next generation’s ability to cope with the new, warmer temperatures.

“We reared spiny chromis damselfish, a common Indo-Pacific reef fish, for two generations under three different water temperatures, up to 3 degrees Celsius warmer than current-day ocean temperatures,” explained co-author Prof Timothy Ravasi of KAUST.

“The next generation appeared to be advantaged by parental exposure to elevated temperatures. The offspring’s altered gene expression, also referred to as ‘acclimation,’ allowed them to maximise oxygen consumption and energy use.”

“Acclimation may buffer populations against the impacts of rapid environmental change and provide time for genetic adaptation to catch up over the longer term,” said Prof Munday.

The authors of the study note that while this is good news for reef fish, the decline of their coral habitat, as a result of climate change, will continue to be an overriding concern for their survival.

The paper “The epigenetic landscape of transgenerational acclimation to ocean warming” is published in Nature Climate Change.

Ryu, T.,  Veilleux, H., Donelson, J.M., Munday, P.L., and Ravasi, T.  (2018), The epigenetic landscape of transgenerational acclimation to ocean warming. Nature Climate Change. DOI: 10.1038/s41558-018-0159-0

Images must carry credits as listed in Dropbox folder: https://www.dropbox.com/sh/khxf9l5l2a9uect/AABp-L10BCkhvgdaVC8SMe6ka?dl=0

 

CONTACTS

Prof Philip Munday

Coral CoE

Phone: +61 (0) 0408 714 794, +61 (0)7 4781 5341 (AEST)

Email: philip.munday@jcu.edu.au

 

Prof Timothy Ravasi

KAUST

Phone: +61 491 333 697 (AEST)

Email: timothy.ravasi@kaust.edu.sa

 

FOR MORE INFORMATION

 

Ms Catherine Naum

Communications Manager

ARC Centre of Excellence for Coral Reef Studies

Phone: +61 (0) 0428 785 895, +61 (0)7 4781 6067 (AEST)

Email: Catherine.Naum1@jcu.edu.au

 

A new study published online today in Nature shows that corals on the northern Great Barrier Reef experienced a catastrophic die-off following the extended marine heatwave of 2016.

“When corals bleach from a heatwave, they can either survive and regain their colour slowly as the temperature drops, or they can die. Averaged across the whole Great Barrier Reef, we lost 30 per cent of the corals in the nine month period between March and November 2016,” said Prof Terry Hughes, Director of the ARC Centre of Excellence for Coral Reef Studies (Coral CoE).

The scientists mapped the geographical pattern of heat exposure from satellites, and measured coral survival along the 2,300-km length of the Great Barrier Reef following the extreme marine heatwave of 2016.

The amount of coral death they measured was closely linked to the amount of bleaching and level of heat exposure, with the northern third of the Great Barrier Reef being the most severely affected. The study found that 29 per cent of the 3,863 reefs comprising the world’s largest reef system lost two-thirds or more of their corals, transforming the ability of these reefs to sustain full ecological functioning.

“The coral die-off has caused radical changes in the mix of coral species on hundreds of individual reefs, where mature and diverse reef communities are being transformed into more degraded systems, with just a few tough species remaining,” said co-author Prof Andrew Baird of Coral CoE at James Cook University.

“As part of a global heat and coral bleaching event spanning 2014-2017, the Great Barrier Reef experienced severe heat stress and bleaching again in 2017, this time affecting the central region of the Great Barrier Reef,” said co-author Dr Mark Eakin of the U.S. National Oceanic and Atmospheric Administration.

“We’re now at a point where we’ve lost close to half of the corals in shallow-water habitats across the northern two-thirds of the Great Barrier Reef due to back-to-back bleaching over two consecutive years,” said Prof Sean Connolly of Coral CoE at James Cook University.

“But, that still leaves a billion or so corals alive, and on average, they are tougher than the ones that died. We need to focus urgently on protecting the glass that’s still half full, by helping these survivors to recover,” said Prof Hughes.

The scientists say these findings reinforce the need for assessing the risk of a wide-scale collapse of reef ecosystems, especially if global action on climate change fails to limit warming to 1.5‒2 °C above pre-industrial levels.

The study is unique because it tests the emerging framework for the International Union for Conservation of Nature (IUCN) Red List of Ecosystems, which seeks to classify vulnerable ecosystems as ‘safe,’ ‘threatened’ or ‘endangered.’

“The Great Barrier Reef is certainly threatened by climate change, but it is not doomed if we deal very quickly with greenhouse gas emissions. Our study shows that coral reefs are already shifting radically in response to unprecedented heatwaves,” said Prof Hughes.

The researchers warn that failure to curb climate change, causing global temperatures to rise far above 2 °C, will radically alter tropical reef ecosystems and undermine the benefits they provide to hundreds of millions of people, mostly in poor, rapidly-developing countries.”

 

Hughes, T.P., Kerry, J.T., Baird, A.H.,Connolly, S.R., Dietzel, A., Eakin, C.M., Heron, S.F., Hoey, A.S., Hoogenboom, M.O., Liu, G., McWilliam, M.J., Pears, R., Pratchett, M.S., Skirving, W.J., Stella, J.S. and Torda, G. (2018) Global warming transforms coral reef assemblages. Nature  doi:10.1038/s41586-018-0041-2

 

IMAGES

Link to video and images here. Please credit as marked.

CONTACTS FOR INTERVIEWS

Prof Terry Hughes
Director, ARC Centre of Excellence for Coral Reef Studies
Phone: +61 (0) 400 720 164 (AEST/UTC +10)
E-mail: terry.hughes@jcu.edu.au

Prof Sean Connolly
ARC Centre of Excellence for Coral Reef Studies at James Cook University
Phone: +61 (0)7 4781 4242 (AEST/UTC +10)
Email: sean.connolly@jcu.edu.au

Prof Andrew Baird
ARC Centre of Excellence for Coral Reef Studies at James Cook University
Phone: +61 (0) 400 289 770 (AEST/UTC +10)
Email: andrew.baird@jcu.edu.au

C. Mark Eakin, Ph. D.
U.S. National Oceanic & Atmospheric Administration
College Park, MD U.S.A.
Phone: +1 (301) 502 8608 (EST/UTC -5)
Email: mark.eakin@noaa.gov

FOR FURTHER INFORMATION

Catherine Naum
Communications Manager
ARC Centre of Excellence for Coral Reef Studies at James Cook University
Phone: +61 (0)7 4781 6067, +61 (0) 428 785 895 (AEST/UTC +10)
Email: catherine.naum1@jcu.edu.au

New research reveals that global warming also affects fish who depend on corals.

The Great Barrier Reef (GBR) is revered for its kaleidoscope of colour. New international research led by PhD student Laura Richardson of the ARC Centre of Excellence for Coral Reef Studies at James Cook University reveals that coral bleaching events not only whitewash corals, but can also reduce the variety of fish occupying these highly-valued ecosystems.

The study was conducted by researchers at James Cook University and Lancaster University, U.K., who examined 16 reefs off Lizard Island, in the northern section of the GBR. The quantity and types of coral and fish species were surveyed before, during and after the 2016 mass bleaching event caused by a global heatwave.

“The widespread impacts of heat stress on corals have been the subject of much discussion both within and outside the research community. We are learning that some corals are more sensitive to heat-stress than others, but reef fishes also vary in their response to these disturbances,” said lead author Ms Richardson.

“Fish assemblages are significantly impacted by loss of coral cover as a result of bleaching events, and some fishes are more sensitive than others,” said co-author Prof Nick Graham of Lancaster University.

The loss of corals affected some types of fish more than others. Following the bleaching event, researchers recorded a sharp drop in the diversity of fish communities as the mix or species changed.

Fish that are highly dependent on branching corals, such as butterflyfish, declined the most.

“Prior to the 2016 mass bleaching event, we observed significant variation in the number of fish species, total fish abundance and functional diversity among different fish communities. Six months after the bleaching event, however, this variation was almost entirely lost,” said co-author Dr Andrew Hoey of ARC Centre of Excellence for Coral Reef Studies at James Cook University.

“Also known as ‘biotic homogenisation,’ this tendency towards individual and community similarity is increasingly considered one of the most pressing, but largely unrecognised, biodiversity crises faced globally.”

Paper: Richardson, L. E., Graham, N.A.J., Pratchett, M.S., Eurich, J.G., and Hoey, A.S. (2018), Mass coral bleaching causes biotic homogenization of reef fish assemblages. Global Change Biology,  doi:10.1111/gcb.14119

Link to video and images here. Please credit as marked.

Contacts for interviews:

Australia

Dr Andrew Hoey
ARC Centre of Excellence for Coral Reef Studies at James Cook University
Townsville, QLD AUSTRALIA
P: +61 7 4781 5979 (AEST/UTC +10)
E: andrew.hoey@jcu.edu.au

UK

Ms Laura Richardson
Exeter University
Exeter, UNITED KINGDOM
M: +44 (0) 7384 634580 (GMT/UTC)
E: laura.richardson1@my.jcu.edu.au

Prof Nicholas Graham
Lancaster University, Lancaster Environment Centre
Lancaster, UNITED KINGDOM
M: +44 (0) 7479 438 914 (GMT/UTC)
E: nick.graham@lancaster.ac.uk

For more information:

Catherine Naum
Communications Manager
ARC Centre of Excellence for Coral Reef Studies at James Cook University
Townsville, QLD AUSTRALIA
Tel: +61 (0)7 4781 6067
M: +61 (0) 428 785 895 (AEST/UTC +10)
E: catherine.naum1@jcu.edu.au

Coral reefs can naturally protect coasts from tropical cyclones by reducing the impact of large waves before they reach the shore, according to scientists.

Tropical cyclones wreak havoc on coastal infrastructure, marine habitats and coastal populations across the world. However, Dr. Michael Cuttler, from the ARC Centre of Excellence for Coral Reef Studies (Coral CoE) at The University of Western Australia (UWA), says that for coastlines facing a direct cyclone impact, a fringing reef can protect the beach from extensive erosion.

“Reefs can effectively protect shorelines because of their ability to cause waves to break offshore, thus limiting the energy impacting the coastline,” he said.

Dr. Cuttler and several of his Coral CoE colleagues studied Ningaloo Reef – Australia’s largest fringing reef system, and a UN World Heritage site – during Tropical Cyclone Olwyn in 2015. Olwyn was a Category 3 severe tropical cyclone that caused extensive damage along the coast of Western Australia.

The team observed that the shoreline remained largely unscathed because of the protection provided by its offshore reef.

“The large waves generated by the cyclone were effectively dissipated by the reef situated offshore,” Dr. Cuttler explained.

“The little erosion that did occur was due to smaller waves that were generated by wind within the lagoon.”

The shape, or geomorphology, of the reef – with its steep forereef slope, shallow reef crest and reef flat, and relatively shallow lagoon – is representative of most fringing reefs worldwide.

“In this study, we also compared similar cyclone impacts on coastlines without reefs and found that these beaches were eroded up to ten times more than the beach at Ningaloo,” Dr. Cuttler said.

While the findings of Dr. Cuttler’s study indicated that coral reefs can effectively protect coastlines from tropical cyclones and other large wave impacts, it also suggested that for reef systems with lagoons, local wind effects cannot be ignored when attempting to model or predict the impact of cyclones.

He also warned that the ability of reefs to protect adjacent coastlines was threatened by both sea level rise and slowing rates of reef accretion.

“These changes may ultimately increase the amount of wave energy reaching the coastline and potentially enhance coastal erosion,” he said.

Few studies before have measured the hydrodynamic conditions and morphological responses of such a coastline in the presence of a tropical cyclone.

Dr. Cuttler and his Coral CoE colleagues found the results could be used to assess coastal hazards facing reef-fringed coastlines due to extreme tropical cyclone conditions, and would become increasingly relevant as climate change alters the status of coral reefs globally.

Paper:  Cuttler, M. V., Hansen, J. E., Lowe, R. J. and Drost, E. J. (2018), Response of a fringing reef coastline to the direct impact of a tropical cyclone. Limnol. Oceanogr., 3: 31-38. doi:10.1002/lol2.10067

IMAGES AVAILABLE HERE.

 

CONTACTS FOR INTERVIEWS

Dr. Michael Cuttler
Coral CoE at UWA
E: michael.cuttler@uwa.edu.au

 

FOR MORE INFORMATION

Jess Reid
UWA/Media and Public Relations Advisor
P: +61 (0) 8 6488 6876 (AWST/UTC +8)
E:  jess.reid@uwa.edu.au

Catherine Naum
Coral CoE/Communications Manager
P: +61 (0) 7 4781 6067 (AEST/UTC +10)
M: +61 (0) 428 785 895
E: catherine.naum1@jcu.edu.au

Scientists have found that high carbon dioxide levels cause squid to bungle attacks on their prey.

PhD candidate Blake Spady from the ARC Centre of Excellence for Coral Reef Studies (Coral CoE) at James Cook University (JCU) led the investigation. He said that the oceans absorb more than one-quarter of all the excess carbon dioxide (CO2) released into the atmosphere by humans and this uptake of additional CO2 causes seawater to become more acidic.

“Climate models project that unless there is a serious commitment to reducing emissions, CO2 levels will continue increasing this century to reach levels that will have far-reaching effects on sea life,” he said.

Mr Spady said the team chose to study cephalopods (a group that includes squid, cuttlefish and octopuses) because while most previous behavioural studies have focused on fishes, the effects of elevated CO2 on highly active invertebrates is largely unknown.

“Cephalopods also prey on just about anything they can wrap their arms around and are themselves preyed upon by a wide range of predator species, so they occupy an important place within marine food webs.”

The scientists tested the effects of elevated CO2 on the hunting behaviours of pygmy squid and bigfin reef squid.

“For pygmy squid, there was a 20% decrease in the proportion of squid that attacked their prey after exposure to elevated CO2 levels. They were also slower to attack, attacked from further away, and often chose more conspicuous body pattern displays at elevated CO2 conditions.

Bigfin reef squid showed no difference in the proportion of individuals that attacked prey, but, like the pygmy squid, they were slower to attack and used different body patterns more often.”

Mr Spady said both species showed increased activity at elevated CO2 conditions when they weren’t hunting, which suggests that they could also be adversely altering their ‘energy budgets’.

“Overall, we found similar behavioural effects of elevated CO2 on two separate cephalopod orders that occupy largely distinct niches. This means a variety of cephalopods may be adversely affected by rising CO2 in the oceans, and that could have significant consequences in marine ecosystems,” said co-author Dr Sue-Ann Watson.

“However, because squid have short lifespans, large populations, and a high rate of population increase, they may have the potential to adapt to rapid changes in the physical environment,” Mr Spady added.

“The fast lifestyle of squid could mean they are more likely to adapt to future ocean conditions than some other marine species, and this is the next question we intend to investigate.”

Paper: Spady, BL, Munday, PL, Watson, S-A (2018) published Predatory strategies and behaviours in cephalopods are altered by elevated CO2 in Global Change Biology doi: 10.1111/gcb.14098

Images: for media use can be found here. Please credit as marked.

Contacts:

Blake Spady
PhD candidate at Coral CoE/ JCU
Phone: +61 456 777 883
Email: blake.spady@my.jcu.edu.au

Dr. Sue-Ann Watson
Senior Research Fellow, Coral CoE
Phone: +61 7 4781 5270
Emailsueann.watson@jcu.edu.au

Prof. Philip Munday
Reef Research Leader, Coral CoE
Phone: +61 7 47815341
Emailphilip.munday@jcu.edu.au

Melissa Lyne
Acting Communications Manager, Coral CoE
Phone: +61 415 514 328
Email: melissa.lyne@jcu.edu.au

 

 

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Phone: 61 7 4781 4000
Email: info@coralcoe.org.au