The federal government is protecting 20 types of colorful coral by putting them on the list of threatened species, partly due to climate change, according to The Associated Press.

As with the polar bear, much of the threat to the coral species stems from problems expected to occur in the future due to global warming, said David Bernhart, an endangered-species official at the National Oceanic and Atmospheric Administration, the AP reported.

These coral species are already being hurt by climate change "but not to the point that they are endangered yet," he said, according to the AP.

Climate change is making the oceans warmer, more acidic and helping with coral diseases like bleaching, and those "are the major threats" explaining why the species were put on the threatened list, Bernhart said in a Wednesday conference call.

Other threats include overfishing, runoff from the land, and some coastal construction, but those are lesserissues, Bernhart stated.

Five species can be found off the Atlantic and Gulf of Mexico coasts of Florida, Puerto Rico and the Virgin Islands, the AP reported. They include pillar coral, rough cactus coral and three species of star coral.

The other 15 are located in the Pacific Ocean area near Guam and American Samoa, but not Hawaii, according to the AP.

The agency considered listing 66 species, but Wednesday listed only 20 for various reasons, the AP reported. All are called threatened, not endangered, and two coral species were already listed.

Coral reefs, which are in trouble worldwide, are important fish habitats, according to the AP. The agency has not yet created any new rules yet to prevent coral from being harvested or damaged.

"There is a growing body of expert scientists talking about a risk of mass extinction in the sea and on land," said Elliott Norse, founder and chief scientist of the Marine Conservation Institute of Seattle. Coral "are organisms on the front line of anything that humans do."

"I hope this wakes people up and we don't have to lose more coral," Norse said, according to the AP.