British Columbia

El Nino is bleaching Christmas Island corals, says UVic scientist

El Nino is causing corals on Christmas Island to bleach because of the warm ocean water temperature.

Corals on the island are starving because of warm water temperatures from El Nino

The corals on Christmas Island are bleaching because of the El Nino event that is happening across the Pacific Ocean and is changing weather patterns around the world. (The Baum Lab)

This year's El Nino is already impacting a small island in the middle of the Pacific Ocean, according to a UVic researcher.

Just a degree and half north of the equator sits Christmas Island — and this year's monster El Nino is causing the corals to bleach. 

"Initially when the coral bleaches it is just sick, but it can die," says Julia Baum, an assistant professor of biology at the University of Victoria. 

Coral bleaching is when the corals let go of the algae that lives in their tissues because the water is too warm. Corals can survive a bleaching event but they are under more stress. 

Baum is a coral researcher and is one of the few people that gets off the plane when it touches down once a week on Christmas Island between stops in Honolulu and Fiji. 

She notes corals are actually animals that have microscopic plants living inside them, which give the corals their vibrant colours. 

"They provide the coral animal with its nutrients," she said, "The coral is providing shelter or protection for the plant." 

But because of this year's intense El Nino the ocean water has heated up as much as three to four degrees and is lasting for months instead of weeks.

"When the water heats up, even a degree or degree and a half, it stresses the corals. The corals don't like it," she said. 

"The reaction to the stress is to kick out the microscopic plants, kick out their food production."

According to the National Atmospheric and Oceanic Administration, in 2005 the U.S. lost half of its coral reefs in the Caribbean because of bleaching.

As climate change warms other bodies of water, Christmas Island could serve as a 'crystal ball' for the world's other reefs, says Baum.

"It is basically allowing us to see the future that other coral reefs are going to experience down the line," she said, "So if we can study Christmas Island and see how corals react to these heat stress events, hopefully we can develop some targeted solutions."


To hear the full interview listen to the audio labelled on Christmas Island corals are bleaching say scientists on the CBC's On The Island.