Snorkel teams can assess climate impact on corals

Deborah Zabarenko, Reuters 20 May 09;

WASHINGTON (Reuters) - Teams of snorkel-wearing scientists could be warriors against the ravages of climate change on coral reefs, the International Union for Conservation of Nature reported on Wednesday.

Small teams of observers, wearing snorkels, swim fins and masks and carrying underwater note paper or slates and measuring tape, could make rapid assessments of how coral formations are faring as the world's oceans get warmer, the group said at a briefing.

Warmer waters can contribute to the bleaching of coral reefs, a process in which microscopic plants that live on and nourish the coral are lost; without these plants, coral can die in a matter of weeks.

Coral reefs are also under threat from ocean acidification as a result of long-term emissions of the greenhouse gas carbon dioxide.

Oceans have absorbed some 525 billion tons of this gas over the last 200 years, about a third of all the carbon dioxide humans have generated; when carbon dioxide combines with sea water, it forms the corrosive carbonic acid.

Coral reefs are considered sentinel ecosystems, one of several on Earth that are now showing the impact of climate change. They also furnish food and medicines to coastal communities worldwide and act as protection for coastlines.

"It's probably one of the first ecosystems, together with maybe mountain systems, that show a global change in response to climate change," said Jerker Tamelander, a specialist in the conservation group's Indian Ocean Marine Program.

"It warns us of future change. ... It also gives us an opportunity, it gives us a testing ground and methods for ensuring adaptation, for ensuring that the systems don't degrade any further," Tamelander said at the briefing.

Global climate change causes much of the damage to coral reefs, but human activities on a local scale -- including overfishing and pollution from agriculture and other land-based sources -- are the main drivers of damage, said the group's Gabriel Grimsditch.

Fast assessments of the coral's condition can help guide policy and ease protection, Grimsditch said.

There are 40 variables that can indicate whether the coral is resilient, but three of the main ones are the size of the coral population, how many plant-eating fish and how big the algae populations are around the reef, Grimsditch said.

Sea level rise, which is projected to occur this century as the world's glaciers melt, would not necessarily kill coral reefs, Tamelander said, since the reefs can grow as waters get higher.

"A healthy reef should be able to keep up," Tamelander said.

Manage corals - Minimize climate change
IUCN 20 May 09;

A better assesment of the threats to coral reefs along with improved management will give corals a much higher chance of survival in the face of warming oceans, says IUCN’s latest report.

“We already know that climate change is destroying coral reefs through warming waters that cause coral bleaching and through acidifying oceans that hinders coral skeleton growth. We also know that if we want to save these beautiful living entities we must do something about it immediately,” says Gabriel Grimsditch, IUCN Corals Expert.

“By better understanding and management of stresses on corals such as unsustainable and destructive fishing practices or unregulated coastal development, we can increase the chance of coral survival, even as climate change warms the oceans.”

The report, Resilience Assessment of Coral Reefs - Rapid assessment protocol for coral reefs, focusing on coral bleaching and thermal stress, shows that the amount of damage done to corals depends not only on the rate and extent of climate change, but also on the ability of coral reefs to cope with change. This report outlines a protocol that defines basic resilience indicators that can be quantified using rapid assessment methods.

“Unmanaged, these stresses have the potential to act in synergy with climate change to functionally destroy many coral reefs,” says David Obura, Director of Coastal Oceans Research and Development East Africa. “While science is providing important insights about climate change impacts on coral reefs, strategies for managing them are only just emerging.”

The need for quick results for measuring coral reef resilience is becoming increasingly acute, especially in the developing world. It is crucial to develop monitoring and assessment protocols to build an understanding of bleaching resistance and resilience indicators for application in management, and to determine how Marine Protected Area management actions can influence resilience and resistance.

"Research assessment for coral reefs builds our understanding of past management actions in maintaining the resilience of coral reefs, and helps managers combat the effects of climate change,” says Carl Gustaf Lundin, Head of IUCN’s Global Marine Programme. “Greater investment must be made in using research findings for adaptive management.”

“The story of coral reefs is particularly powerful and compelling, being one of the first ecosystems to clearly show climate change impacts, and being well-understood, highly visible and charismatic,” adds Lundin. “As a result, increasing our knowledge base of resilience-based science, management and policy for coral reefs has broader value for other ecological and human systems globally.”

“Findings from coral reefs should be more efficiently incorporated into the United Nations’ climate change negotiations in Copenhagen in December.”

Download the report: Resilience Assessment of Coral Reefs: Rapid assessment protocol for coral reefs, focusing on coral bleaching and thermal stress (2.32MB)