A quarter mile beneath the ocean’s surface in Ecuador’s Galápagos Marine Reserve, scientists have discovered ancient, deep-sea coral reefs—the first of their kind ever documented in the marine protected area. The reefs stretch about 1.2 miles long and appear largely untouched by human activities, which researchers say is a very uncommon find.
“In other surveyed deep-sea reef areas, there are often examples of lost fishing gear, rubbish such as cans, bottles and plastic bags, or even areas that have obviously been trawled and thus cleared of all their reef structure,” Michelle Taylor, a deep-sea marine biologist at the University of Essex in England and a co-leader of the expedition, tells Gizmodo’s Lauren Leffer. “However, this reef was pristine; just a dense mass of layers of ancient coral with a frosting of live coral across the top.”
The newfound reefs are also “rare,” Taylor tells the publication, because of their high percentage of live coral. In the deep sea, 10 to 20 percent coral cover is considered the norm, per a statement from the Woods Hole Oceanographic Institution (WHOI). In these cases, the remaining 80 to 90 percent of the reef consists of dead coral skeletons, which still provide habitat for marine life. But these Galápagos reefs have 50 to 60 percent live corals in some areas, supporting pink octopus, batfish, squat lobsters and an array of deep-sea fish, sharks and rays.
“This is encouraging news,” José Antonio Dávalos, the environment minister for Ecuador, says in the statement. “It reaffirms our determination to establish new marine protected areas [MPAs] in Ecuador and to continue promoting the creation of a regional marine protected area in the eastern tropical Pacific.”
Coral reefs, sometimes called “rainforests of the sea,” are some of the most biodiverse ecosystems on Earth. They support about 25 percent of all known marine species, rake in billions of dollars for fisheries and tourism and help protect shorelines from erosion. In the U.S. alone, the total economic value of coral reef services is about $3.4 billion.
But since 1950, scientists estimate the world has lost half of all its coral reefs because of climate change, overfishing and pollution. Corals are particularly sensitive to temperature changes in the water, which can often cause them to expel the symbiotic algae that lives within coral tissue. This process, also called coral bleaching, leaves them vulnerable to starvation. As of now, about 75 percent of all coral reefs in the world are threatened by climate change and other human activities, and without concerted efforts to save them, scientists estimate 99 percent will be gone by the end of the century.
Deep-water reefs, like the ones found off the Galápagos, are usually less affected by bleaching and temperature increases, but over time, even they cannot escape the effects of climate change, Gizmodo writes.
Scientists came across the Galápagos reefs while diving to explore uncharted areas of the Galápagos Marine Reserve in the submersible Alvin, which has previously been used to explore the Titanic wreck.
El Niño weather in 1982 and 1983 was thought to have wiped out nearly all the structural shallow coral reefs around the islands, with Wellington Reef in the archipelago’s north assumed to be one of the only survivors, per WHOI. But the recent discovery indicates that these sheltered deep-sea reefs likely have endured for centuries in the marine reserve. Such finds can help inform management and conservation decisions.
“These newly discovered reefs are potentially of global significance—a ‘canary in the mine’ for other reefs globally—sites which we can monitor over time to see how pristine habitats evolve with our current climate crisis,” Taylor says in the statement.