HONOLULU (HawaiiNewsNow) - By Erica Marie-Louise Barry
A newly-released survey of coral bleaching off West Hawaii found wide swaths of coral colonies have died off, and researchers say the findings underscore a need to act quickly to address climate change and save coral reefs.
The survey, conducted in 2015 by the Nature Conservancy of Hawaii in partnership with other organizations, focused on reefs off North Kona and South Kohala.
The study took place after a major bleaching incident that caused significant damage to the reefs.
The results were shocking -- with a mortality rate of 32 to 90 percent in bleached coral colonies.
Dr. Eric Conklin, the conservancy's director of marine science, said rising water temperatures spell "bad news for coral reefs."
Higher temperatures can result in coral bleaching. When waters become too warm, corals expel the algae living in their tissues, turning them completely white. This significantly raises coral mortality rates.
The conservancy is working to identify actions that communities who rely on reefs can take to protect reefs from damage.
Given limited resources, it is important "to understand which reefs have the best chance of surviving into the future," said Charles Wiggins, the conservancy's Hawaii Island marine director.
Human threats, such as overfishing, sedimentation and nutrient pollution, all contribute to coral mortality rates.
According to Conklin, we need to "manage the threats that we can, like reducing fishing pressure on fish that protect reef health by keeping them clean of harmful algae."
The study's authors say the next step is to present the survey results to government and community partners so that they can incorporate coral resilience into their management actions.
The conservancy hopes to repeat the survey in 2016 to see where and how the reefs have recovered, and continue to find solutions in order to keep coral reefs healthy and thriving for generations to come.