Temperature affects the early life history stages of corals more than near future ocean acidification

Chua, Chia-Miin, Leggat, William, Moya, Aurelie, and Baird, Andrew (2013) Temperature affects the early life history stages of corals more than near future ocean acidification. Marine Ecology Progress Series, 475. pp. 85-92.

PDF (Published Version) - Published Version
Download (235kB)
View at Publisher Website: http://dx.doi.org/10.3354/meps10077


Climate change is projected to increase ocean temperatures by at least 2°C, and levels of pH by ~0.2 units (ocean acidification, OA) by the end of this century. While the effects of these stressors on marine organisms have been relatively well explored in isolation, possible interactions between temperature and OA have yet to be thoroughly investigated. OA at levels projected to occur within this century has few direct ecological effects on the early life history stages of corals. In contrast, temperature has pronounced effects on many stages in the early life history of corals. Here, we test whether temperature might act in combination with OA to produce a measurable ecological effect on fertilization, development, larval survivorship or metamorphosis of 2 broadcast spawning species, Acropora millepora and A. tenuis, from the Great Barrier Reef. We used 4 treatments: control, high temperature (+2°C), high partial pressure of CO₂ (pCO₂) (700 µatm) and a combination of high temperature and high pCO₂, corresponding to the current levels of these variables and the projected values for the end of this century under the IPCC A2 scenario. We found no consistent effect of elevated pCO₂ on fertilization, development, survivorship or metamorphosis, neither alone nor in combination with temperature. In contrast, a 2°C rise in temperature increased rates of development, but otherwise had no consistent effect on fertilization, survivorship or metamorphosis. We conclude that OA is unlikely to be a direct threat to the early life history stages of corals, at least in the near future. In contrast, rising sea temperatures are likely to affect coral population dynamics by increasing the rate of larval development with resulting changes in patterns of connectivity.

Item ID: 24976
Item Type: Article (Research - C1)
ISSN: 1616-1599
Keywords: coral reefs, climate change, connectivity, development, larval ecology, survivorship, settlement
Additional Information:

Article openly accessible from publisher website.

Funders: Australian Research Council (ARC)
Date Deposited: 18 Feb 2013 23:52
FoR Codes: 06 BIOLOGICAL SCIENCES > 0602 Ecology > 060205 Marine and Estuarine Ecology (incl Marine Ichthyology) @ 60%
05 ENVIRONMENTAL SCIENCES > 0501 Ecological Applications > 050101 Ecological Impacts of Climate Change @ 40%
SEO Codes: 96 ENVIRONMENT > 9603 Climate and Climate Change > 960307 Effects of Climate Change and Variability on Australia (excl. Social Impacts) @ 10%
97 EXPANDING KNOWLEDGE > 970106 Expanding Knowledge in the Biological Sciences @ 90%
Downloads: Total: 303
Last 12 Months: 43
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page