Fish diet heats up marine biodiversity hotspot
Scientists have discovered a never-before-seen biodiversity pattern of coral reef fishes that suggests some fishes might be exceptionally vulnerable to environmental change. A new study shows plank
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
Corals can survive the early stages of their development even under the tough conditions that rising carbon emissions will impose on them says a new study from the ARC Centre of Excellence for Coral Reef Studies.
Globally, ocean acidification due to the burning of fossil fuels remains a major concern and scientists say it could have severe consequences for the health of adult corals, however, the evidence for negative effects on the early life stages of corals is less clear cut.
Dr Andrew Baird, Principal Research Fellow at the ARC Centre of Excellence for Coral Reef Studies and James Cook University, was part of the research team and explains their findings.
“The prevailing view is that ocean acidification will act like a toxin to corals, but we were unconvinced by results from previous work on young corals and ocean acidification so we tested critical early stages of development in several coral species at several different acid (or ‘pH’) concentrations of seawater.
“Our results showed no clear response to increasing ocean acidification in any of the stages, or for any of the coral species,” says Dr Baird. “In fact, in only one of nine experiments did we get the response expected if CO2 was acting like a toxin. More often than not we found no effect.”
By bubbling CO2 through seawater the research team was able to simulate future levels of ocean acidification expected to result from rising human carbon emissions. They tested the success of embryo development, the survival of coral larvae and finally their success in settling on coral reefs.
Although their results suggest that ocean acidification may not affect the early stages of coral development, the team warn that this does not mean acidification is not a threat to corals.
“Undoubtedly, as the oceans become more acidic adult corals are going to struggle to build their skeletons, which might hinder their ability to grow, reproduce and compete for space on reefs. We also have to remember that the oceans are getting warmer, so corals will be dealing with higher temperatures, as well as higher acidity.
“Fortunately, before corals settle on to reefs they don’t need to grow a skeleton, which might explain why they are apparently unaffected in by higher levels of ocean acidification,” says Dr Chia-Miin Chua, the lead author of the study.
“This message is reinforced when we look at the early life stages of creatures that do need a larval skeleton, such as sea urchins and oysters. In these cases we see early life stage development slowing down as acidity increases.”
However the study does not discount the possibility that coral larvae may suffer other ill-effects from increasing ocean acidification, for example, their swimming speeds may slow down, but because coral larvae typically settle on the reef two or three weeks after birth it is unlikely that these effects will have a major impact on the survival or settlement of coral larvae.
Dr Baird says that while the long-term outlook for corals may be gloomy, this research highlights the fact that not all life stages of corals will be equally affected.
The paper “Near-future reductions in pH will have no consistent ecological effects on the early life-history stages of reef corals” by Chia-Miin Chua, William Leggat, Aurelie Moya and Andrew Baird is available online in the journal Marine Ecology Progress Series
Further information please contact:
Dr Andrew Baird, CoECRS, +61 (04) 00 289770 or andrew.baird@jcu.edu.au
Dr Bill Leggat, CoECRS, +61 (04) 15 253820 or bill.leggat@jcu.edu.au
Jenny Lappin, CoECRS, +61 (0)7 4781 4222
Scientists have discovered a never-before-seen biodiversity pattern of coral reef fishes that suggests some fishes might be exceptionally vulnerable to environmental change. A new study shows plank
Scientists say stable seafood consumption amongst the world’s poorer coastal communities is linked to how local habitat characteristics influence fishing at different times of the year. In the co
An international group of scientists is predicting markedly different outcomes for different species of coral reef fishes under climate change – and have made substantial progress on picking the ‘
New research has found as climate change causes the world’s oceans to warm, baby sharks are born smaller, exhausted, undernourished and into environments that are already difficult for them to survi
Abstract: The vast majority of reef fishes have a life history consisting of a pelagic larval phase of typically 20 to 60 days, followed by larval settlement where they remain through their juvenile a
Abstract: Social networks have been and remain important across the Pacific Islands, and beyond, for building and maintaining social-ecological resilience. However, there is little quantitative infor
Abstract: The global conservation community is comprised of a range of organisations, processes, and professionals. Given the diversity of these actors, and the complexity of the systems that conser
Abstract: Seasons create a rhythm in nature and, by extension, in the lives of people who depend directly on natural resources. However, our understanding of how seasons affect the ways that people
Abstract: Oceanic shark populations have declined 77% over the past 60 years as a result of overexploitation in fisheries. However, sustainable shark management is limited to a few developed nations
Abstract: Vertigo3 is a new class of small, fast and agile ‘true-flight’ underwater glider, purposely designed for robotic, artificial intelligence-assisted broadscale marine surveys, and capable
Abstract: Recurrent marine heat waves are leading to widespread coral bleaching, transforming the structure and function of tropical coral reefs. Past bleaching events have highlighted large variatio
Abstract: Shallow-water tropical seascapes typically include a range of habitat types such as coral reefs, mangroves, macroalgal and seagrass beds. These habitats can occur in close proximity and are
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