[Coral-List] Coral Bleaching Watch for Papahanaumokuakea Marine National Monument

Andy Collins andy.collins at noaa.gov
Wed Aug 11 14:48:01 EDT 2010


We wanted you to be the first to know about the potential of coral
bleaching events in the Northwestern Hawaiian Islands this year.  The
attached document provides the latest information on coral bleaching as
an initial step toward multi-agency monitoring of the situation and
response if necessary.  Please do not hesitate to contact us if you need
additional information or have questions.

2010 Bleaching Forecast for Papahānaumokuākea Marine National Monument

Papahānaumokuākea Marine National Monument (PMNM) is one of the most
pristine and best protected coral reef ecosystems in the world.  While
PMNM’s management is designed to best support the ecosystem’s resilience
to climate change, these measures cannot completely prevent damage from
climate change.

One of the effects of climate change is to increase the risk of reef
damage through mass coral bleaching events.  Mass coral bleaching occurs
when unusually warm water temperatures disrupt the relationship between
corals and the symbiotic microscopic algae that live within their
tissues. Temperature stress causes the coral to expel the algae, and the
reef appears white or “bleached” as its calcium carbonate skeleton
becomes visible.  Coral bleaching was recorded in PMNM in 2002 and 2004,
and is likely to occur again in the future

Papahānaumokuākea Marine National Monument is co-managed through a
partnership of the Department of the Interior’s U.S. Fish and Wildlife
Service, the Department of Commerce's National Oceanic and Atmospheric
Administration, and the State of Hawaii.  PMNM works with a network of
leading scientists to assess bleaching risks and impacts by monitoring
climate forecasts, sea temperatures, and coral conditions throughout the
bleaching season (July-November).

2010 Forecast
Based on available information, the threat of widespread coral bleaching
within PMNM is currently rated as low to moderate

Globally, 2010 has been a significant year for mass coral bleaching.
Severe events in Thailand, Malaysia, and Indonesia have caused up to
100% bleaching in some areas, resulting in high levels of coral
mortality.  The regional heat event that caused this extreme event in
Southeast Asia has recently moved toward Micronesia, with reports of
bleaching already reported in Palau.  Climate forecasts raise concern
that a similar heating event may warm sea temperatures in PMNM beyond
bleaching thresholds.

Predictions developed by NOAA’s Coral Reef Watch Program suggest that
the bleaching risk is greatest to Papahānaumokuākea’s northern atolls:
Kure, Pearl and Hermes, and Midway; the highest temperature stress is
likely to occur in September 2010.  However, local weather conditions,
including either storms or doldrums, will strongly influence the actual
sea temperatures and could either prevent or worsen a mass bleaching

Current measurements of sea temperature by both satellites and in-water
instruments indicate slightly above average temperatures and a very
minor accumulation of heat stress.  Research cruises in August and
September will provide an update on sea temperatures and coral
condition, which will be described in subsequent condition reports.

For further information, please contact NOAA’s Research Coordinator for
PMNM (heidi.schuttenberg at noaa.gov).


Leadership & Staff
Papahanaumokuakea Marine National Monument
a World Heritage Site

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