By Stephen Palumbi
Corals are dying off in large numbers around the world. Here’s why we are working to save them.
Coral reefs are dying off around the world. To further his work on the issue, Dr. Stephen Palumbi, director of Stanford’s Hopkins Marine Station, Pew Fellow in Marine Conservation, and OWOO Science Advisor is in American Samoa and the Cook Islands in search of the corals most likely to survive. This is the second in a series of special reports from the field that will continue throughout his team’s three-week expedition.
By Stephen Palumbi, PhD.
Why are we going to all this effort to find the world’s strongest corals? The short answer: they form a global safety net.
The palette of corals and color on a healthy reef at Ofu Island. Photo by Stephen Palumbi.
Hundreds of millions of people depend on reefs – among Earth’s most productive ecosystems in terms of biomass and fast growth rates – for food. For many families, reefs put food on the table when budgets are tight. Elsewhere, local villages depend on coral reefs to fuel tourism and keep storm waves at bay. Steve Hall of the World Fish Center calls this a socio-natural safety net. When corals die, the safety net fails, not only for humans but for entire ecosystems, from tiny plankton, to gentle giants like the manta ray.
Beyond their practical value, corals are simply mind-blowing. They are wonders of the living world, and grow enough hard rock to build whole archipelagoes. The thousands of species that live within reefs are the most intensely colored living paintings you will ever see.
Yet corals are dying fast. Buried by dirt from runoff, poisoned by pollution, smothered by fertilizer-fed algae that grows like a plague, corals have died on about a quarter of all the reefs in the world. Rising temperatures and ocean acidity, due to climate change, threatens a third of all corals with extinction.
Verrucosa. Photo by Stephen Palumbi.
We originally went to Ofu, in American Samoa, because the shallow water in the lagoons between the shoreline and the outer barrier reefs gets up to 93 degrees F (34C), much too hot for corals to live. We knew if we found corals there, they would be different, and better at surviving. We found them. In fact, we found ones that grow even faster than the same species in other places.
Now we want to know why.
We also want to find more of these strong corals, and protect them in a grand alliance with political leaders of reef nations around the world. It would be a profound step toward restoring the safety net that supports us all.
A school of surgeon fish at the Ofu lagoon. Healthy reefs have a lot of fish, which help maintain corals by eating fast-growing algae. Photo by Stephen Palumbi.