Algae make corals vulnerable to bleaching
Washington: Corals may be more severely impacted by climate warming when they contain too many symbiotic algae, a new study by scientists at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science has revealed
The single-celled algae living inside corals are usually the key to coral success, providing the energy needed to build massive reef frameworks. However, when temperatures become too warm, these algae are expelled from corals during episodes of coral ‘bleaching’ that can lead to widespread death of corals
Until now, it was thought that corals with more algal symbionts would be more tolerant of bleaching because they had ‘more symbionts to lose.’ The new study shows that the opposite is true.
“We discovered that the more symbiotic algae a coral has, the more severely it bleaches, showing that too much of a good thing can actually be bad,” said Ross Cunning, Ph.D. student and lead author of the study.
“We also learned that the number of algae in corals varies over time, which helps us better understand coral bleaching risk,” he stated.
His research was conducted using cauliflower coral (Pocillopora damicornis) collected from the Pacific coast of Panama. The corals were monitored for six months at the UM’s Experimental Hatchery, where they slowly warmed up and ultimately bleached
The number of symbiotic algae in the corals was studied by analyzing DNA samples with new highly sensitive genetic techniques that determine the ratio of algal cells to coral cells. This improved technique made the discovery possible by showing that corals with more algae bleached more severely than those with fewer algae.
“Corals regulate their symbionts to match the environment in which they are found, and this study shows there is a real cost to having too many,” said co-author Andrew Baker, associate professor at UM’s Rosenstiel School.
“There are real-world implications of this. Corals will be more vulnerable to bleaching if they are found in environments that increase the number of symbionts, such as coastal reefs polluted by wastewater and runoff.
If we can improve water quality, we might be able to buy some time to help these reefs avoid the worst effects of climate change.
“Other environmental changes, including ocean acidification as a result of increasing carbon dioxide emissions, might also influence bleaching vulnerability in ways we haven’t thought of before,” Baker added.
More from India
More from World
More from Sports
More from Entertaiment
- Will Shiv Sena join hands with Congress to stop BJP from entering BMC?
- Watch: PM Narendra Modi addressing rally in Imphal
- Coimbatore: PM Narendra Modi unveils 112-foot tall bust of Lord Shiva
- Panel discussion on Farooq Abdullah's remark on terrorists
- DNA: Why depression cases are increasing rapidly in India?
- WATCH: Kieron Pollard's epic celebration after destroying Lahore Qalandars in Dubai
- Indian doctor rescued from ISIS recounts horror, says 'they forced me to watch videos, shot me thrice'
- Mitchell Johnson takes a dig at Anil Kumble over calling Steve O'Keefe 'steady'
- India vs Australia, 1st Test, Day 3: As it happened...
- Pune Test: Virender Sehwag could have saved India from embarrassment, says former Aussie stars