As world government leaders prepare to discuss climate change at next week’s 2009 Climate Conference in Copenhagen, the Endangered Species Coalition issued its list of "10 Hottest Species" endangered by global warming. Making the nonprofit’s list are the Caribbean’s elkhorn coral, already included as a threatened species on the federal Endangered and Threatened Species list.
Additionally, the list included the leatherback turtle, which nests in the Virgin Islands.
While the plight of elkhorn and other corals isn’t new news, Jeff Miller, who heads the National Park Service’s Inventory and Monitoring Program, said calling attention to it can’t hurt.
"It’s very hard for people to understand the problems that happen under water," the St. John-based Miller said.
Elkhorn coral grows across the territory. Miller pointed out that the elkhorn coral surrounding Buck Island Reef National Monument on St. Croix is one of the main reasons it became a Park Service facility. The coral also grows in V.I. National Park on St. John, a fact noted by www.nationalparkstraveler.com in a Thursday story that linked the "10 Hottest Species" to national park facilities around the country.
The affect of global warming on coral hit the news in 2005 when elkhorn and other corals across the territory were hit hard with bleaching, a disease in which warm water causes the corals to expel the algae that gives them their color.
Coral is sensitive to changes in water temperature.
"They like it when it’s nice and toasty, but when it’s too warm they don’t like it; but different species have different tolerances," Miller said.
According to the coalition’s press release, mass bleaching events have become much more frequent and severe as ocean temperatures have risen in recent decades. Scientists predict that most of the world’s corals will be subjected to mass bleaching events at deadly frequencies within 20 years if carbon dioxide emissions continue on their current path.
Another related threat for coral is ocean acidification. Caused by the ocean’s absorption of carbon dioxide, acidification impairs the ability of corals to build their protective skeletons. According to the coalition’s press release, scientists have predicted that most of the world’s coral reefs will disappear by mid-century due to global warming and ocean acidification, unless carbon dioxide pollution is rapidly reduced.
As for the leatherback turtles, the "10 Hottest Species" report indicates that as warmer waters expand, ice covers recede, circulation patterns change, and the pH of the oceans declines. Leatherbacks and all six other species of marine turtles will be affected by freshwater from melting glaciers, changes in salinity and oxygen, and altered ocean chemistry as shifts occur in currents, key habitats, and the range and abundance of prey species.
According to the press release, 20 to 30 percent of the world’s species will be at an increased risk of extinction if global temperature increases exceed three to five degrees above pre-industrial levels. The global warming threats to species include increased disease, diminished reproduction, lost habitat, reduced food supply, and other impacts.