Global Coral Bleaching Event puts Reefs at Risk

Researchers announced this month that a massive global coral bleaching event is jeopardizing the health of coral reefs around the world, and the crisis is still heating up. A triple threat of climate change, El Niño and a climate change-induced “warm blob” in the Pacific is causing the ocean to reach unusually high temperatures, stressing the coral animals that build reefs—the cradles of tropical marine life—and causing them to bleach, a stress response that often causes corals to starve, sicken and die. Researchers from the National Oceanic and Atmospheric Administration (NOAA) have gathered evidence suggesting that about 12% of reefs worldwide have already bleached in the last year, and predict that nearly half of those affected (over 12,000 square kilometers, or over 5% of reefs) could disappear forever. Moreover, this warming trend may continue through 2016 making this bleaching event persist over the course of two years—longer than any previously recorded global bleaching episode.

© XL Catlin Seaview Survey

This is only the third global coral bleaching event ever observed, with the first in 1998 decimating 16-19% of the world’s coral reefs and the second in 2010. While coral reefs cover less than one percent of the world’s seafloor, they support approximately one quarter of all life in the ocean. Small but prolific coral polyps grow atop one another to compose vast, complex habitat structures for thousands of fish and invertebrate species that support food webs around the globe. An estimated 500 million people’s livelihoods depend on healthy coral reefs, with worldwide reef-based economies totaling over $30 billion in value. These benefits to humanity are at stake if we allow coral reefs to decline, as is the wellbeing of countless species that depend on reefs for survival.

Bleaching occurs when corals become stressed, commonly from elevated sea temperatures. This stress —> Read More