“Relationships between people have important consequences for the long-term availability of the natural resources we depend on,” Dr Barnes says.
“Our results suggest that when fishers—specifically those in competition with one another—communicate and cooperate over local environmental problems, they can improve the quality and quantity of fish on coral reefs.”
Co-author Prof Nick Graham, from Lancaster University (previously at JCU), adds: “Coral reefs across the world are severely degraded by climate change, the pervasive impacts of poor water quality, and heavy fishing pressure. Our findings provide important insights on how fish communities can be improved, even on the reefs where they are sought.”
Dr Barnes and her team interviewed 648 fishers and gathered underwater visual data of reef conditions across five coral reef fishing communities in Kenya.
They found that in the places where fishers communicated with their competitors about the fishing gear they use, hunting locations, and fishing rules, there were more fish in the sea—and of higher quality.
Co-author Dr Jack Kittinger, Senior Director at Conservation International’s Center for Oceans, says this is likely because such cooperative relationships among those who compete for a shared resource—such as fish—create opportunities to engage in mutually beneficial activities. These relationships also help build trust, which enables people to develop a shared commitment to managing resources sustainably.
“This is why communication is so critical,” says Dr Kittinger. “Developing sustained commitments, such as agreements on rules, and setting up conflict resolution mechanisms, are key to the local management of reefs.”
“The study demonstrates that the positive effect of communication does not necessarily appear when just anyone in a fishing community communicates – this only applies to fishers competing over the same fish species,” adds co-author Dr Örjan Bodin, from the Stockholm Resilience Centre at Stockholm University.
The study advances a framework that can be applied to other complex environmental problems where environmental conditions depend on the relationships between people and nature.
Co-author Dr Orou Gaoue, from the University of Tennessee Knoxville, emphasises this broad appeal.
“Although this study is on coral reefs, the results are also relevant for terrestrial ecosystems where, in the absence of cooperation, competition for non-timber forest products can quickly lead to depletion even when locals have detailed ecological knowledge of their environment.”
“Environmental problems are messy,” explains Dr Barnes. “They often involve multiple, interconnected resources and a lot of different people—each with their own unique relationship to nature.
“Understanding who should cooperate with whom in different contexts and to address different types of environmental problems is thus becoming increasingly important,” she concludes.
* * *
Barnes M, Bodin O, McClanahan T, Kittinger J, Hoey A, Gaoue O, Graham N (2019). ‘Social-ecological alignment and ecological conditions in coral reefs’. Nature Communications. DOI: 10.1038/s41467-019-09994-1
PHOTOS & VIDEO
Images relating to the study are available here for media use with this story only. Any use must carry the credit as stated.
Researchers have discovered some good news for fish populations living on coral reefs hit by climate change.
Renato Morais is a PhD candidate from the ARC Centre of Excellence for Coral Reef Studies (Coral CoE) at James Cook University (JCU). He led a study that looked at how fish on a bleached coral reef get their food.
“We already knew that coral reef fish rely on food drifting in from the sea, such as plankton,” Mr Morais said.
“But, we didn’t know exactly how important this was,” he said.
Mr Morais and Professor David Bellwood, also from Coral CoE at JCU, combined high-resolution surveys and individual biomass production estimates to generate the first map of where the energy comes from for all fish on a coral reef.
“We looked at everything from gobies to coral trout and large jacks, assessing more than 18,000 fish from over 300 species,” said Mr Morais.
“We found that various transport mechanisms, such as currents and tides, interact with the reef and bring in vast amounts of plankton.”
The pair found that for every kilogram of fish produced on the reef more than 400 grams of that kilogram relied on food derived from the open ocean, rather than the reef itself. This rises to almost 600 grams on the side of the reef facing the open ocean.
“This means, that for many reefs, food from outside can sustain fish populations, even when the coral is badly damaged,” Prof Bellwood said.
The scientists found that areas of the reef that were more exposed to the open ocean produced the largest quantities of fish – with reef slopes being the most fruitful.
“The discovery that reef fish get so much of their food from off-reef sources was encouraging, especially because many species that feed on oceanic material have a history of disappearing after coral loss,” said Mr Morais.
“This is the first time we have been able to put all species in perspective,” said Prof Bellwood. “Our study offers hope that reefs subject to coral loss can still be productive.”
“The reefs may be damaged but they are still incredibly valuable.”
The unique study measured how many adult corals survived along the length of the world’s largest reef system following extreme heat stress, and how many new corals they produced to replenish the Great Barrier Reef in 2018. The loss of adults resulted in a crash in coral replenishment compared to levels measured in previous years before mass coral bleaching.
“The number of coral larvae that are produced each year, and where they travel to before settling on a reef, are vital components of the resilience of the Great Barrier Reef. Our study shows that reef resilience is now severely compromised by global warming,” said co-author Professor Andrew Baird.
“The biggest decline in replenishment, a 93% drop compared to previous years, occurred in the dominant branching and table coral, Acropora. As adults these corals provide most of the three-dimensional coral habitat that support thousands of other species,” he said.
“The mix of baby coral species has shifted, and that in turn will affect the future mix of adults, as a slower than normal recovery unfolds over the next decade or longer.”
“The decline in coral recruitment matches the extent of mortality of the adult brood stock in different parts of the Reef,” added Professor Hughes. “Areas that lost the most corals had the greatest declines in replenishment.”
“We expect coral recruitment will gradually recover over the next five to ten years, as surviving corals grow and more of them reach sexual maturity, assuming of course that we don’t see another mass bleaching event in the coming decade,” he said.
So far, the Great Barrier Reef has experienced four mass bleaching events due to global warming, in 1998, 2002, and back-to-back in 2016 and 2017. Scientists predict that the gap between pairs of coral bleaching events will continue to shrink as global warming intensifies.
“It’s highly unlikely that we could escape a fifth or sixth event in the coming decade,” said co-author Professor Morgan Pratchett.
“We used to think that the Great Barrier Reef was too big to fail – until now,” he said.
“For example, when one part was damaged by a cyclone, the surrounding reefs provided the larvae for recovery. But now, the scale of severe damage from heat extremes in 2016 and 2017 was nearly 1500km—vastly larger than a cyclone track.”
Professor Pratchett added that the southern reefs that escaped the bleaching are still in very good condition, but they are too far away to replenish reefs further north.
“There’s only one way to fix this problem,” says Hughes, “and that’s to tackle the root cause of global heating by reducing net greenhouse gas emissions to zero as quickly as possible.”
Hughes T, Kerry J, Baird A, Connolly S, Chase T, Dietzel A, Hill T, Hoey A, Hoogenboom M, Jacobson M, Kerswell A, Madin J, Mieog A, Paley A, Pratchett M, Torda G, & Woods R (2019). ‘Global warming impairs stock–recruitment dynamics of corals’. Nature: http://dx.doi.org/10.1038/s41586-019-1081-y
PHOTOS & VIDEO
A selection of photos and videos relating to the study is available here. Please note that any use of this imagery MUST carry the credit given. In addition, permission must be obtained from the ARC Centre of Excellence for Coral Reef Studies for any use beyond this story.
The Australian Academy of Science have produced a video based on the study. The files are available to embed in online stories at the Dropbox hyperlink above, and the YouTube embed link is here.
CONTACTS FOR INTERVIEWS
Prof Terry Hughes (Pacific Coast Time Zone, USA) Director, ARC Centre of Excellence for Coral Reef Studies Phone: +61 (0)400 720 164 Email: firstname.lastname@example.org
Prof Andrew Baird (Eastern Australia Time Zone) ARC Centre of Excellence for Coral Reef Studies Phone: +61 (0)7 4781 4857 Mobile: +61 (0)400 289 770 Email: email@example.com
Prof Morgan Pratchett (Eastern Australia Time Zone) ARC Centre of Excellence for Coral Reef Studies Phone: + 61 (0)7 4781 5747 Mobile: +61 (0)488 112 295 Email: firstname.lastname@example.org
FOR FURTHER INFORMATION
Melissa Lyne (Eastern Australia Time Zone) Media Manager, ARC Centre of Excellence for Coral Reef Studies Phone: +61 (0) 415 514 328 Email: email@example.com
Centre researcher awarded prestigious Fulbright Fellowship
A Centre scientist has won a prestigious fellowship that will allow her to examine how environmental management can lead to positive outcomes for people and nature.
Environmental social scientist Dr Georgina Gurney has been awarded a Fulbright Postdoctoral Fellowship that will allow her to spend five months in the United States collaborating with leading researchers and practitioners in sustainability and environmental governance.
Dr Gurney’s research focuses on understanding how communities, government agencies and non-government organisations work together or co-manage environmental resources in the Asia-Pacific region. She is based at the Australian Research Council Centre of Excellence for Coral Reef Studies at James Cook University.
“Achieving global sustainability is one of the most pressing challenges of our time,” Dr Gurney said.
“We need to find ways in which environmental co-management and other forms of environmental governance can deliver outcomes across the three pillars of sustainability: society, the environment, and the economy.”
Dr Gurney’s project involves working with Professor Arun Agrawal at the University of Michigan, where they will investigate the trade-offs and benefits among the multiple social, environmental and economic outcomes of co-management.
“We will be examining the similarities and differences that lead to successful outcomes in managing coral reef fisheries and tropical forests in multiple countries,” Dr Gurney said.
She will also be spending time at Harvard University’s Kennedy School of Government, where she will collaborate with Professor Bill Clark and the international non-profit the Wildlife Conservation Society to develop a decision-support tool to guide co-management for multiple outcomes.
“Although compromises are inevitable in co-management, this project aims to develop ways to mitigate severe trade-offs between outcomes,” Dr Gurney said.
“In a nutshell, the research seeks to understand what co-management practices work, where to contribute to sustainability and to foster the incorporation of this knowledge in real-world co-management practice.”
The Fulbright Program is the flagship foreign exchange scholarship program of the United States of America, aimed at increasing bi-national collaboration, cultural understanding, and the exchange of ideas.
Photo available on Dropbox. Credit: Australian-American Fulbright Commission
Contact: Dr. Georgina Gurney ARC CoE for Coral Reef Studies P: +61 (0) 415 465 712 (AEST/GMT+10)
JCU Media Contact: Bethany Keats JCU Media Liaison P: +61 (0) 7 4781 4586 (AEST/GMT+10)
No silver bullet for the Great Barrier Reef
Recent north Queensland flooding and the mass outflows of polluted water onto the Great Barrier Reef have focused attention on the impact of water quality on the Reef’s health.
But new research reveals that even if water quality is improved, it won’t be enough on its own to save the Great Barrier Reef.
Because of the flooding, rivers have dumped millions of litres of polluted water onto the Reef, but until now the impact of these events on reef corals and marine life has been difficult to assess.
“We found the Great Barrier Reef is an ecosystem dominated by runoff pollution, which has greatly reduced the resilience of corals to multiple disturbances, particularly among inshore areas,” said lead author Dr. Aaron MacNeil of Dalhousie University.
“These effects far outweigh other chronic disturbances, such as fishing, and exacerbate the damage done by crown-of-thorns starfish and coral disease. Perhaps most critically, poor water quality reduced the rates at which coral cover recovers after disturbances by up to 25 percent. This shows that, by improving water quality, the rates of reef recovery can be enhanced.”
“Our results provide strong support for government policies aimed at reducing nutrient pollution to help increase the resilience of the Great Barrier Reef, in recovering from damage due to tropical cyclones, crown-of-thorns outbreaks and coral bleaching,” said co-author PhD candidate Sam Matthews of Coral CoE.
Yet the effects of water quality only go so far. Using a series of scenarios modelling future changes in climate and the likelihood of coral bleaching, the team found that no level of water quality improvement was able to maintain current levels of coral cover among the most scenic and valuable outer-shelf reefs that sustain much of the reef tourism industry.
Dr. Camille Mellin of the University of Adelaide noted that: “Coral reefs, including the Great Barrier Reef, are subject to an increasing frequency of major coral die-off events associated with climate change driven by coral bleaching. With these increasingly common disturbances becoming the new normal, the rate of coral recovery between disturbances has become incredibly important.”
“While the effects of improved water quality on recovery rates of inshore reefs were encouraging, our analysis puts into perspective the limits of how much reducing pollution in river runoff can do to improve the state of the outer Great Barrier Reef.
“No level of water quality improvement will be sufficient to ensure maintenance of the clear water reefs on the outer shelf, the very reefs that tourists come to Australia to see.”
“What these results emphasise is that there is no silver bullet for addressing the threats facing the Great Barrier Reef,” said Dr MacNeil.
“Clearly reducing pollution in river runoff can have widespread, beneficial effects on reef corals and should continue to be supported. But for areas of the reef not impacted by water quality, our emphasis must be on mitigating carbon emissions to slow down climate change.
“We must give our reefs the time and conditions to recover. Without that, the most stunning and iconic parts of the reef will soon decline and be unrecognisable from their current form.”
For interviews please contact:
Sam Matthews ARC Centre of Excellence in Coral Reef Studies/James Cook University, Townsville Australia P: c/o Melissa Lyne on +61 (0) 0415 514 328 (AEST/GMT+10) E: firstname.lastname@example.org
Camille Mellin Australian Institute of Marine Science/University of Adelaide, Adelaide Australia P: +61 4 3635 6396 (ACDT) E: email@example.com
Paper: MacNeil M, Mellin C, Matthews S, Wolff NH, McClanahan TR, Devlin M, Drovandi C, Mengersen K, & Graham NAJ. (2019) Water quality mediates resilience on the Great Barrier Reef. Nature Ecology & Evolution: http://dx.doi.org/10.1038/s41559-019-0832-3
Melissa Lyne (Australia) Acting Communications Manager ARC Centre of Excellence for Coral Reef Studies P: +61 (0) 0415 514 328 (AEST/GMT+10) E: firstname.lastname@example.org
Niecole Comeau (Canada) Communications, Faculty of Science, Dalhousie University P: +1 (902) 494-8443, +1 (902) 223-2446 (ADT/GMT-4) E: email@example.com
Exploring the deep reef
Scientists have taken a rare look at the depths of the Great Barrier
Reef and have discovered they’re teeming with a kaleidoscope of life.
And they say conservation planners should take into account their
findings to better protect the international icon.
ARC Centre of Excellence for Coral Reef Studies at James Cook University PhD candidate Tiffany Sih led the study, which used Baited Remote Underwater Video Stations (BRUVS) and multi-beam sonar to examine the reef down to 260 metres.
“The ecology of deeper habitats along the Great Barrier Reef has rarely
been investigated. While we know habitat like coral is important for
shallower fish species, there was little understanding of how important reef
habitat is to fish in deeper environments,” said Ms Sih.
She said the lack of information was due to the expense of doing
research at these depths, which often requires specialist divers, remotely
operated submersibles or mini-submarines.
Instead, the team sampled 48 sites between 54 and 260 metres deep in the
central GBR using sonar and a relatively simple BRUVS rig, which attracts fish
with bait and films them.
“We found the ecology of deeper reef fish communities is fundamentally
different from those found at shallower depths. Depth and reef composition was
important, but habitat preferences clearly had a role in determining the
distribution of fish species.
Both the living components of the habitat – such as algae, soft corals
and sponges, as well as big boulders or mud flats – contribute to the structure
and complexity of the reef, which has an effect on what kind of fish you find
there,” said Ms Sih.
She said when the rules around fishing in the Great Barrier Reef Marine Park were determined over a decade ago, less environmental data was available for the deeper habitats.
“They took into account what they did not know, and allowed for some uncertainty, by designating some of the deeper areas as no-take zones and zones where certain types of fishing, like bottom-trawling, were banned. But now the technology exists where we can map the deeper areas and fully document the fish community,” said Ms Sih.
She said that in the future it will be important to compare deeper fish communities in the Great Barrier Reef Marine Park and to consider deeper reefs as essential neighbourhoods where communities of fish thrive.
Reduced salinity of seawater wreaks havoc on coral chemistry
New research confirms that drastic changes in ocean salinity from, for example, severe freshwater flooding, as recently experienced off the coast of north-east Queensland from abnormal monsoonal conditions, provoke a similar stress response in corals as extreme heating, resulting in “freshwater bleaching” and if unabated, coral death.Researchers from the ARC Centre of Excellence for Coral Reef Studies at James Cook University (Coral CoE) and University of Technology Sydney (UTS) report that extreme and sudden changes in salinity, or the ocean salt concentration, cause a biochemical response in corals that is similar to marine heatwaves, but in some ways, more damaging to their cells ability to function.
sensitive organisms, known to only tolerate slight changes in their
environment. Thriving in clear, sunlit waters – the majority of reef-building
corals are found in tropical and subtropical waters with a salinity between 32
to 42 parts per thousand,” said senior author Prof David Miller of
recent flooding, there are reports that nearshore reefs were exposed to roughly
half the normal ocean salinity.”
research shows that this kind of environmental change causes a shock response
in corals that prevents normal cell function.”
researchers used the sequenced genome – a biological blueprint – of the common
reef-building coral, Acropora millepora to detect changes in the coral’s biology.
sophisticated labs at the National Sea Simulator, we put
both young and adult corals under a salinity stress test to see how they
respond to differing salinity concentrations,” said co-author Dr
Jean-Baptiste Raina of UTS.
that there was a common response between both coral life-stages – with the
younger corals being more sensitive to low salinity conditions, but faring
slightly better with exposure over time.”
general, we found that the coral’s cells launch a similar chemical response to
reduced salinity as they do for heat stress,” Prof Miller explained.
unlike the heat stress response, corals exposed to reduced salinity experience
a complete collapse of their internal cellular protein balance, suggesting that
their cells are in deep trouble.”
the central Great Barrier Reef may have been spared mass thermal bleaching due
to higher-than-normal ocean temperatures this summer, there are many coastal
reefs left battling dramatic changes in water conditions from the massive
plumes of floodwater.
frequency and severity of heavy rainfall and runoff events predicted to
increase by 2050, management interventions to increase the resilience of reefs
are needed now more than ever.
Paper: Aguilar C, Raina J-B, Fôret S, Hayward DC, Lapeyre B, Bourne DG, Miller DJ (2019). Transcriptomic analysis reveals protein homeostasis breakdown in the coral Acropora millepora during hypo-saline stress. BMC Genomics 20:148
Corals know how to attract good company. New research finds that corals emit an enticing fluorescent green light that attracts the mobile microalgae, known as Symbiodinium, that are critical to the establishment of a healthy partnership.
“Most reef corals can not function without Symbiodinium,” said Shunichi Takahashi from the National Institute of Basic Biology.
“Following the back-to-back mass bleaching events, images of bleached white coral contrasted with healthy, vibrantly coloured coral were widespread. The key difference between the two is the abundance of Symbiodinum in the coral’s tissue. Without sufficient Symbiodinum, which provide corals with nutrients via photosynthesis, the coral will starve.”
“Thirty percent of corals receive their Symbiodinium from their parents, the other seventy percent, need a different mechanism” said co-author Professor Andrew Baird of Coral CoE.
But what brings the two organisms together? Corals are stationary creatures, however Symbiodinium can move freely through the water column.
The study reveals that corals have evolved a cunning ability to draw the Symbiodinium to them.
The researchers used the chalice coral, Echinophyllia aspera, to test whether the green fluorescent light emitted by corals under certain conditions can signal the Symbiodinium in the water column to move towards them: a process known as “positive phototaxis.”
“Our research identifies a novel biological signaling tool that underlies the success of a relationship essential for healthy coral reef ecosystems, ” said Prof Baird.
IMAGES Link to images here. Please credit as marked.
CONTACT FOR INTERVIEW Prof Andrew Baird ARC Centre of Excellence for Coral Reef Studies at James Cook University Phone: +61 (0) 400 289 770, +61 (0)7 4781 4857 (AEST/UTC +10) Email: firstname.lastname@example.org
FOR FURTHER INFORMATION Catherine Naum, Communications Manager ARC Centre of Excellence for Coral Reef Studies Townsville, QLD AUSTRALIA P: +61 7 4781 5979, +61 (0)428 785 895 (AEST/UTC +10) E: email@example.com
Murky water keeps fish on edge
A study led by researchers at the ARC Centre of Excellence for Coral Reef Studies at James Cook University found fish become anxious and more cautious when water quality is degraded by sediment, an effect that could stunt their growth and damage their health.
“Suspended sediment concentrations in tropical coastal waters have increased substantially over the past few decades as a result of human activities. We wondered if this reduced visibility affected fish performance, especially their ability to escape predators,” she said.
The scientists, led by PhD student Sybille Hess, examined the response of one-month-old cinnamon anemonefish to a simulated predator attack after they had been living in a sediment-filled tank for seven days.
“We found the fish responded faster and were able to dart away from the simulated predator attack more effectively than those living in clear-water, which suggests the fish are on high alert owing to the decrease in visibility,” said Ms Hess.
She said fish in turbid water were also less active when looking for food and avoided open areas.
“But while the faster responses and more cautious foraging may increase survival rates in low-visibility environments where predators are present, there is a price to be paid.”
Dr Rummer said the additional energy spent avoiding predators reduces the energy available for growth, maintenance and reproduction, and may ultimately have equal or greater effects on prey populations than predators themselves.
“It’s particularly bad for juvenile reef fishes, as survivorship is already quite low during this critical life-history stage.”
She said that while juvenile anemone-fish frequently migrate between sea anemones, with which they have a symbiotic relationship, such behaviour could be too risky under turbid conditions.
“More cautious behaviour, such as we observed in elevated suspended sediments, may not only reduce movement within their home range, potentially limiting their access to food, but may also reduce the ability of juveniles to find a suitable anemone to call home.
“Just simply enduring reduced visibility may be enough to affect fish. When fish feel as though they are constantly at risk, this perceived risk takes energy away from other important tasks – side-effects could include impaired growth and a compromised immune system.”
Dr Rummer said predators that depend on clear water conditions to catch their prey may also be affected by turbid conditions, which will be the next question for the team to investigate.
Citation: Hess, S, Allan, BJM, Hoey, AS et al. (2019) Enhanced fast-start performance and anti-predator behaviour in a coral reef fish in response to suspended sediment exposure. Coral Reefs 38(1): 103-108
Dr Jodie Rummer E: firstname.lastname@example.org M: 0439 166 171
Fifty years of decline in Queensland’s coastal sharks
Queensland’s coastal shark numbers are continuing a 50-year decline, in sharp contradiction of suggestions of ‘exploding’ shark populations, according to an analysis of Queensland Shark Control Program data.
Researchers from the ARC Centre of Excellence for Coral Reef Studies at The University of Queensland (CoralCoE) and Griffith University analysed data from the program, which has used baited drumlines and nets since 1962 to minimise human-shark interactions, and now spans 1760 km of the Queensland coastline.
“Explorers in the 19th century once described Australian coastlines as being ‘chock-full of sharks’, yet we don’t have a clear idea of how many sharks there used to be on Queensland beaches,” he said.
“Shark populations around the world have declined substantially in recent decades, with many species being listed as vulnerable and endangered.”
By analysing the Queensland Shark Control Program data, the research team reconstructed historical records of shark catches to explore changes in the number and sizes of sharks over the past half century.
“What we found is that large apex sharks such as hammerheads, tigers and white sharks, have declined by 74 to 92 per cent along Queensland’s coast,” Dr Roff said.
“And the chance of zero catch – catching no sharks at any given beach per year – has increased by as much as seven-fold.”
“The average size of sharks has also declined – tiger sharks and hammerhead sharks are getting smaller.”
“We will never know the exact numbers of sharks in our oceans more than half a century ago, but the data points to radical changes in our coastal ecosystems since the 1960s.”
“The data acts as a window into the past, revealing what was natural off our beaches, and provides important context for how we manage sharks.”
“What may appear to be increases in shark numbers is in reality a fraction of past baselines, and the long-term trend shows ongoing declines.”
“While often perceived as a danger to the public, sharks play important ecological roles in coastal ecosystems.”
“Large apex sharks are able to prey on larger animals such as turtles, dolphins and dugongs, and their widespread movement patterns along the coastline connects coral reefs, seagrass beds and coastal ecosystems.”
“Such losses of apex sharks is likely to have changed the structure of coastal food webs over the past half century.”
Citation: Roff G, Brown CJ, Priest MA & Mumby PJ. (2018) Decline of coastal apex shark populations over the past half century. Communications Biology 1:223
Dr George Roff, email@example.com, +61 432 931 051
Dr Christopher Brown, firstname.lastname@example.org, +61 439 835 343
A glimmer of hope for the world’s coral reefs
The future of the world’s coral reefs is uncertain, as the impact of global heating continues to escalate. However, according to a study published today in Nature Climate Change, the response of the Great Barrier Reef to extreme temperatures in 2017 was markedly different to one year earlier, following two back-to-back bouts of coral bleaching. Remarkably, corals that bleached and survived 2016 were more resistant in 2017 to a recurrence of hot conditions.
“Dead corals don’t bleach for a second time. The north lost millions of heat-sensitive corals in 2016, and most of the survivors were the tougher species. As a result of bleaching, the mix of species is changing very rapidly,” said lead author Prof Terry Hughes, Director of the Australian Research Council Centre of Excellence for Coral Reef Studies (Coral CoE), headquartered at James Cook University. “We were astonished to find less bleaching in 2017, because the temperatures were even more extreme than the year before,” he said. The new research highlights the extent of damage, or “geographic footprint” of multiple coral bleaching events across the 2,300 km length of the world-heritage listed area.
The back-to-back heatwaves bring the total number of mass bleaching events on the Great Barrier Reef to four over the past two decades (in 1998, 2002, 2016 and 2017). The scientists found that only 7% of the Great Barrier Reef escaped bleaching entirely since 1998, and after the 2017 event, 61% of reefs have now been severely bleached at least once.
“We found, using the National Oceanic and Atmospheric Administration’s (NOAA) satellite-based coral bleaching tools, that corals in the north of the Great Barrier Reef were exposed to the most heat stress in 2016. A year later, the central region saw the most prolonged heating,” said co-author Dr Mark Eakin, from NOAA’s Coral Reef Watch program, in Maryland, USA.
The southern third of the Great Barrier Reef was cooler in both years due to local weather conditions, and escaped with only minor bleaching.
“It’s only a matter of time before we see another mass-bleaching event, triggered by the next marine heatwave, driven by global heating,” said co-author Dr Andrew Hoey of Coral CoE at James Cook University. “One of the worst possible scenarios is we’ll see these southern corals succumb to bleaching in the near future.”
“The outcome in 2017 depended on the conditions experienced by the corals one year earlier. We called that ‘ecological memory,’ and show that these repeating events are now acting together in ways that we didn’t expect,” said Prof Hughes.
“We’ve never seen back-to-back mass coral bleaching before on the Great Barrier Reef, in two consecutive summers. The combined footprint has killed close to half of the corals on two-thirds of the world’s largest reef system,” said Dr Hoey.
“We need urgent global action on greenhouse emissions to save the world’s coral reefs. Australia should be – but regrettably isn’t – at the forefront of tackling global heating,” said Prof Hughes.
Citation: Hughes TP, Kerry JT, Connolly SR, Baird AH, Eakin CM, Heron SF, Hoey AS, Hoogenboom MO, Jacobson M, Liu G, Pratchett MS, Skirving W & Torda G (2019). Ecological memory modifies the cumulative impact of recurrent climate extremes. Nature Climate Change Vol 9, pp 40–43
IMAGES Link to video and images here. Please credit as marked.
They found that on reefs where closely related butterflyfish species ranges overlap, the differences in colour patterns between the two were most pronounced.
The team used high-resolution digital colour photographs to quantify colour patterns and explore how they were influenced by evolutionary processes.
“Our results show that, over millions of years, butterflyfishes have evolved the greatest diversity of visual markings when they live in the same area as other, closely related species,” said lead author and PhD student Christopher Hemingson.
“Crucially, we also found that this only happens when both species have ranges that are of similar sizes,” said Mr Hemingson.
“We were surprised to find that when one species’ range is a lot larger than the neighbouring species, the pattern is reversed – with the colour pattern of overlapping species found to be less different,” said co-author Dr Peter Cowman.
Professor David Bellwood, a co-author and senior investigator, noted that this is the first time geographic range dynamics have been shown to be an important predictor of colour differences among marine fish species.
“This research is the first of its kind to quantify colour and pattern differences simultaneously among butterflyfish species. It showed us that colour pattern differences can evolve very quickly among species (within 300,000 years) but then remain stable over millions of years,” said Professor Bellwood.
“Colour is far more complicated than just looking different from other species,” said Mr Hemingson.
“These colour patterns also depend specifically on what other species are also present. It is an interesting piece to the puzzle and may help explain why reef fishes are so colourful.”
Citation: Hemingson, RF, Cowman, PF, Hodge, JR & Bellwood, DR (2018). Colour pattern divergence in reef fish species is rapid and driven by both range overlap and symmetry. Ecology Letters DOI: 10.1111/ele.13180
Images available here. Please attribute as indicated.
December marks the 50th anniversary of the paper that popularized the concept of tragedy of the commons: it argued that individuals will always take advantage of a common resource and so degrade it. A new paper argues that the theory limits the way climate change is viewed.
“New findings about how people understand and act suggest that climate change will more likely be solved by appealing to moral arguments rather than purely scientific ones,” said Professor Katrina Brown, one of the paper’s authors.
Professor Brown and Professor Neil Adger, both from the University of Exeter, and Professor Joshua Cinner from the ARC Centre of Excellence for Coral Reef Studies at James Cook University, say that in order to make urgently needed progress in addressing climate change, governments need to promote climate change as a moral issue. And policy needs acknowledge that politicians often make their decisions based on reputation.
“Doing the right thing matters to people, but not everyone agrees what the right thing is. Some people emphasize fairness, others duty and patriotism. We need to appeal to the full range of these values,” said Professor Cinner, co-author of the new paper in the journal Global Environmental Change.
They argue new ways of speaking about climate change that focus on the wide variety values and priorities of people with conservative and liberal views should be harnessed to encourage more concern and action on climate change.
American ecologist and philosopher Garrett Hardin wrote his paper “The tragedy of the commons” in 1968.
Lead author, Professor Brown, said: “Hardin’s theory has been very influential. It has been used to design global co-operation on climate change such as the Paris Agreement. But there is a rapidly closing window to transform the economy and avoid climate catastrophe.
“New social science points the way to political mobilization based on sense of duty, respect for nature and others, and solidarity. These are now more relevant and more likely to win the day.”
“Addressing climate change requires building inclusive moral frames, and fundamental changes in governance systems to better manage the associated risks.”
Citation: Brown, K, Adger, WN, & Cinner, JE (2019) Moving climate change beyond the tragedy of the commons. Global Environmental Change 54: 61-63. DOI: 10.1016/j.gloenvcha.2018.11.009
For More Information:
University of Exeter, UK Press Office P: +44 (0)1392 724828 E: email@example.com
Catherine Naum, Communications Manager ARC Centre of Excellence for Coral Reef Studies Townsville, QLD Australia P: +61 7 4781 6067 E: firstname.lastname@example.org
Friends matter in climate change response
A James Cook University scientist is investigating how people’s social networks prompt them to take action on climate change – or discourage them from doing so – in an attempt to help communities and government adapt in response to calamitous predictions of global warming.
Dr Michele Barnes, Research Fellow at JCU’s ARC Centre of Excellence for Coral Reef Studies, is leading the project.
Dr Barnes said that the relationships we have with others – our social networks – can profoundly influence our behaviour and our capacity for action.
“What our friends and acquaintances think, say and do can have important effects on our thoughts and actions. Yet while these connections can be reliably mapped, understanding how they prompt action in response to climate change is still in its infancy.”
“It’s usually assumed that capacity to act automatically translates into action, but that’s not necessarily true. So, I’m aiming to uncover the key social factors that help or hinder action. This will be the first study to track individuals and a governance institution both before and after a coral bleaching event,” she said.
The research will focus on the Great Barrier Reef and communities based around reefs in Kenya.
“The project will significantly improve our understanding of how adaptive capacity – the ability of a system to adapt when its environment is changing – translates into adaptive action, or how it fails to do that.”
Dr Barnes said that even under the most optimistic greenhouse gas emissions scenario from the Intergovernmental Panel on Climate Change, the future of biodiversity and ecosystems is under serious threat and that researchers needed to look at how both people and institutions will react.
“Considering the scope and intensity of climate change, it’s vital people can make informed decisions to reduce their vulnerability. Likewise, building flexible governance institutions with the capacity to adapt is crucial.”
Dr Barnes said national and local governments, development agencies, and non-governmental organisations urgently need the knowledge the research will produce.
“Without a thorough understanding of what aspects of social networks translate into adaptive action, and the role of powerful groups and individuals in shaping these outcomes, their efforts risk being unproductive or harmful,” she said.
Six researchers at the ARC Centre of Excellence for Coral Reef Studies at James Cook University (Coral CoE) have been listed amongst the world’s most influential scientists.
Clarivate Analytics has published the list of the top 1% of the globe’s researchers, based on data related to how often other researchers cite their published work.
JCU’s Provost, Professor Chris Cocklin, said it’s a great achievement for so many of the University’s researchers to be included in the list, up from three the previous year.
“These are researchers tackling some of the world’s biggest challenges, including climate change and threats to biodiversity.
“Their inclusion here confirms that, in addition to the significance of their work in its own right, they are also having a positive impact by influencing and inspiring other researchers worldwide.
“Whenever other researchers cite their work, whether it’s as the basis for further enquiry, as supporting evidence, or as new ideas to be challenged and tested, they are playing an essential role in driving science forward, leading the search for the knowledge and ideas needed to build a better future.”
The researchers included in the world’s top 1% of most-cited authors:
Professor Joshua Cinner is a Reef Research Leader. He uses social science to improve coral reef management and has worked with coastal peoples in the Pacific Islands, South East Asia, East Africa, and the Caribbean to better understand how socioeconomic factors influence the ways in which people use, perceive, and govern coral reefs.
Distinguished Professor Geoff Jones is a Chief Investigator at Coral CoE. He has published a career total of more than 280 refereed papers since 1980, mostly on the ecology, behaviour and conservation of marine fishes on tropical coral reefs and in temperate kelp forests.
Distinguished Professor Terry Hughes is Director of the Centre, headquartered at JCU. His research focuses on the linkages between the ecology of reefs and their importance for societies and economies.
Professor Philip Munday leads the Coral Reef Ecology team at Coral CoE. His research focuses on understanding and predicting the impacts that climate change will have on populations and communities of marine fishes, both directly through changes in the physical environment and indirectly through effects on coral reef habitat.
Professor Morgan Pratchett is a Chief Investigator at Coral CoE. He researches major disturbances that impact coral reef ecosystems, with a view to understanding differential responses and vulnerabilities among coral reef organisms.
Distinguished Professor Bob Pressey leads the Conservation Planning group. The group’s activities span theory, modelling, applied studies, and extensive engagement with practitioners across Australia, the Asia-Pacific region, and further afield.
Our researchers are in excellent company – this year’s list includes 17 Nobel laureates.
While the United States tops the national rankings with 2639 researchers in the top one per cent, Australia ranks fifth with 245. Australia’s listings have more than doubled in four years, with 80 researchers making the list in 2014 to 170 in 2018.
“Robust” corals primed to resist coral bleaching
A world-first study has revealed that “robust” reef-building corals are the only known organisms in the animal kingdom to make one of the “essential” amino acids, which may make them less susceptible than other corals to global warming.
In a new paper published today in the prestigious journal Genome Biology, the researchers report that “robust” corals possess a unique capacity to generate an “essential” amino acid.
“Amino acids are the building blocks of life,” said lead author Dr Emily Ying of the ANU Research School of Biology.
“They are crucial, for example, in repairing tissue or growing new tissue. But, generating amino acids is energetically costly for animals, so they usually only generate 11 of the 20 required for life.”
“The remaining nine amino acids are called the ‘essential’ amino acids because they must be supplied by the animal’s diet. For corals, this includes tiny drifting animals known as ‘zooplankton.’”
But this is not the only form of sustenance for corals. Through a mutually-beneficial relationship with microalgae known as Symbiodinium, corals are supplied the energy needed to build their hard skeletons.
“Symbiodinium also supplies the coral with some of the ‘essential’ amino acids, making them less dependent on their diet than other animals,” said senior author Prof David Miller of Coral CoE at JCU.
For example, when global warming causes corals to bleach, they expel their resident Symbiodinium and are therefore suddenly fully dependent on their diet to meet this nutritional requirement.
“We now know that ‘robust’ corals can make at least one of the ‘essential’ amino acids without relying on Symbiodinium. This suggests that they may be more resilient, at least in the short term, to bleaching than the ‘complex’ corals such as the branching staghorns,” explained Prof Miller.
Until now, scientists had few clues about why some corals only host a specific Symbiodinium type and others are less particular.
“Our research also suggests that ‘robust’ corals are less choosey about which species of microalgae can take up residence in the coral’s tissue. The ability to host a broader range of Symbiodinium types could facilitate more rapid acclimation to higher temperatures,” said Prof Miller.
Note to editor:
• Since 1996, coral taxonomists have recognised the existence of two “superfamilies” of reef-building corals: “robust” and “complex.”
• Symbiodinium is a photosynthetic micro-alga that has a mutually beneficial relationship with reef-building corals – in exchange for the stable environment inside the coral cells, it supplies most of the energy needs of the host animal.
• Coral bleaching is the loss of Symbiodinium by coral hosts when they are stressed –especially by high temperatures. Symbiodinium cells depart from stressed corals, which makes the corals pale.
Citation: Ying, H, Cooke, I, Sprungala, S, Wang, W, Hayward, DC, Tang, Y, Huttley, G, Ball, EE, Forêt, S, Miller, DJ (2018) Comparative genomics reveals the distinct evolutionary trajectories of the robust and complex coral lineages. Genome Biology 19:175 DOI: 10.1186/s13059-018-1552-8
Check out Prof. Miller’s related talk from the 2018 “Coral Reef Futures” Symposium:
Fish give up the fight after coral bleaching
Researchers have found that when water temperatures heat up for corals, fish ‘tempers’ cool down, providing the first clear evidence of coral bleaching serving as a trigger for rapid change in reef fish behaviour.
Publishing in Nature Climate Change this week, researchers from Lancaster University and collaborating institutes including the ARC Centre of Excellence for Coral Reef Studies (Coral CoE) at James Cook University show how the iconic butterflyfish, considered to be sensitive indicators of reef health, can offer an early warning sign that reef fish populations are in trouble.
The international team of researchers spent more than 600 hours underwater observing butterflyfish over a two-year period encompassing the unprecedented mass coral bleaching event of 2016.
Led by Dr. Sally Keith of Lancaster University, previously Center for Macroecology, Evolution and Climate, the team examined 17 reefs across the central Indo-Pacific in Japan, the Philippines, Indonesia and Christmas Island (Indian Ocean).
During the initial data collection, the researchers were unaware that the catastrophic bleaching event was on the horizon. Once underway, the researchers realised that this serendipitous ‘natural experiment’ placed them in a unique position to see how fish changed their behaviour in response to large-scale bleaching disturbance.
The team sprang into action to repeat their field observations, collecting a total of 5,259 encounters between individuals of 38 different butterflyfish species. Within a year after the bleaching event it was clear that, although the same number of butterflyfishes continued to reside on the reefs, they were behaving very differently.
“We observed that aggressive behaviour had decreased in butterflyfish by an average of two thirds, with the biggest drops observed on reefs where bleaching had killed off the most coral,” said Dr Keith. “We think this is because the most nutritious coral was also the most susceptible to bleaching, so the fish moved from a well-rounded diet to the equivalent of eating only lettuce leaves – it was only enough to survive rather than to thrive.”
Such changes in behaviour may well be the driver behind more obvious changes such as declining numbers of fish individuals and species. The finding has the potential to help explain the mechanism behind population declines in similarly disrupted ecosystems around the world.
Co-author Dr. Erika Woolsey of Stanford University said: “By monitoring behaviour, we might get an early warning sign of bigger things to come.”
“Our work highlights that animals can adjust to catastrophic events in the short term through flexible behaviour, but these changes may not be sustainable in the longer-term,” added co-author Prof Andrew Baird of Coral CoE at James Cook University.
The paper “Synchronous behavioural shifts in reef fishes linked to mass coral bleaching” is available online here.
As further support for that notion, the team also found the victims – other fish that had apparently been nibbled on – in the same limestone deposits in South Germany (the quarry of Ettling in the Solnhofen region) where this piranha-like fish was found.
“This is an amazing parallel with modern piranhas which feed predominantly not on flesh but the fins of other fishes. It’s a remarkably smart move as fins regrow, a neat renewable resource. Feed on a fish and it is dead; nibble its fins and you have food for the future.”
The newly described fish is part of the world famous collections in the Jura-Museum in Eichstätt. It comes from the same limestone deposits that contained the first feathered proto-bird known as Archaeopteryx.
Careful study of the fossilized specimen’s well preserved jaws revealed long, pointed teeth on the exterior of the vomer, a bone forming the roof of the mouth, and at the front of both upper and lower jaws. Additionally, there are triangular teeth with serrated cutting edges on the pre-articular bones that lie along the side of the lower jaw.
The tooth pattern and shape, jaw morphology and mechanics suggest a mouth equipped to slice flesh or fins, the international team of researchers report. The evidence points to the possibility that the early piranha-like fish may have exploited aggressive mimicry in a striking parallel to the feeding patterns of modern piranha.
“We were stunned that this fish had piranha-like teeth,” Dr Martina Kölbl-Ebert of Jura-Museum Eichstätt (JME-SNSB) said.
“It comes from a group of fishes (the pycnodontids) that are famous for their crushing teeth. It is like finding a sheep with a snarl like a wolf. But what was even more remarkable is that it was from the Jurassic.”
“Fish as we know them, bony fishes, just did not bite flesh of other fishes at that time. Sharks have been able to bite out chunks of flesh, but throughout history bony fishes have either fed on invertebrates or largely swallowed their prey whole. Biting chunks of flesh or fins was something that came much later,” Kölbl-Ebert explained
Or, so it had seemed.
“The new finding represents the earliest record of a bony fish that bit bits off other fishes, and what’s more, it was doing it in the sea,” Bellwood said, noting that today’s piranhas all live in freshwater.
“So when dinosaurs were walking the earth and small dinosaurs were trying to fly with the pterosaurs, fish were swimming around their feet tearing the fins or flesh off each other.”
The researchers call the new find a “staggering example of evolutionary versatility and opportunism.” With one of the world’s best known and studied fossil deposits continuing to throw up such surprises, they intend to keep up the search for even more fascinating finds.
Citation: Kölbl-Ebert, M, Ebert, M, Bellwood, DR & Schulbert, C (2018) A Piranha-like Pycnodontiform Fish from the Late Jurassic. Current Biology 278(21): 3516 – 3521 DOI: 10.1016/j.cub.2018.09.013
Reef researcher wins prestigious queensland science award
A researcher at the ARC Centre of Excellence for Coral Reef Studies at James Cook University has received one of Queensland’s most prestigious science prizes – the Queensland Young Tall Poppy Scientist of the Year award.
The annual Queensland Young Tall Poppy Science Awards were announced last night in Brisbane. The awards recognise and celebrate the achievements of young Queensland researchers and their commitment to science engagement.
The Assistant Director of the ARC Centre of Excellence for Coral Reef Studies at James Cook University, Dr Alana Grech, was recognised as the Queensland Young Tall Poppy Scientist of the Year.
Dr Georgina Gurney – also from the Centre of Excellence for Coral Reef Studies at James Cook University – was recognised as a Young Tall Poppy Science award winner.
JCU Provost Professor Chris Cocklin has congratulated Dr Grech and Dr Gurney on their awards.
“This is a wonderful achievement for both researchers and is richly deserved recognition.
“The University is proud of the work of its researchers, and these awards reflect the depth of research excellence at James Cook University, particularly in the field of coral reef management,” Prof. Cocklin said.
In previous years, JCU has had significant success in the Young Tall Poppy awards. In 2017, five JCU researchers received Queensland Young Tall Poppy Science Awards, and in 2014 JCU’s Dr Sue-Ann Watson was named Queensland Young Tall Poppy Scientist of the Year.
“We have an amazing array of scientists doing extraordinary things in Queensland. It’s important to celebrate this scientific excellence and achievement, to inspire young Australians to pursue careers in science and to help raise the profile of science in the broader community,” Minister Enoch said.
Dr Grech’s research involves using geographic information systems to predict and map changes in coastal wildlife and habitats, with a particular focus on seagrass meadows in the Great Barrier Reef.
“My models allow me to predict locations where human activities, such as poor water quality, coastal development and fishing, are potentially damaging the environment, to help inform environmental policy and practice to protect the reef.”
Dr Gurney is an Environmental Social Science Research Fellow whose research focuses on the human dimensions of environmental governance and management, specifically relating to coral reefs in the Asia-Pacific region.
“By identifying the conditions under which management contributes to people’s well-being and is supported by them, my research helps decision-makers develop effective management strategies that positively affect coral reefs and the communities that depend upon them.”
The annual Queensland Young Tall Poppy Science Awards are hosted by the Australian Institute of Policy and Science in partnership with the Office of the Queensland Chief Scientist.
“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.
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: email@example.com
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: firstname.lastname@example.org