FORT LAUDERDALE, Fla. >> Here’s the estimated price for restoring two declining coral species found in South Florida and the Caribbean: About $250 million.

How long will it take? 400 years or so (assuming all goes smoothly).

No one expected it would be easy to restore elkhorn and staghorn corals, the once-abundant, reef-building species that since the 1970s have vanished from almost all of their old range. A recovery plan just released by the National Marine Fisheries Service says the biggest current threat is climate change, a problem beyond its power to solve.

Assuming the oceans continue to warm, the plan recommends about two dozen steps to help these species survive. Among them: Growing them in nurseries for transplantation to the ocean floor, tightening fishing regulations, identifying resilient genetic strains, improving sewage treatment and reducing the amount of fertilizer and other pollutants washing into the ocean.

“While the climate threats are the most significant, reducing the local threats will provide a buffer for the species to be able to deal with the climate threats,” said Jennifer Moore, a fisheries service biologist.

Often compared to tropical rain forests, coral reefs support a vast range of marine life, from sea anemones and sponges to angelfish and lemon sharks. They are among South Florida’s major tourist attractions, drawing visitors for fishing, diving and snorkeling, accounting for about $483 million in national recreation spending.

Elkhorn and staghorn corals, which can be found in the reefs that stretch from the Florida Keys through Palm Beach County, have been declining for at least 40 years from a variety of causes.

An outbreak of white-band disease wiped out about 80 percent of them in the early 1980s, Moore said. Rising ocean temperatures have made them more vulnerable to bleaching, in which they expel the colorful algae on which they depend for energy.

“Climate change is beginning to creep up in terms of causes,” Moore said. “The indications are that bleaching events will become more frequent and more severe due to climate change.”

The plan puts a price tag of $254,540,000 for recovery but admits it is “an extreme underestimate,” considering what other countries in the Caribbean also would have to spend.

Among the costs: Basic research on their genetics, physiology and resistance to disease ($9.6 million), developing a program to monitor them ($1 million per year), increasing land-based nurseries ($10 million per year), restocking sea urchins that clear algae from corals ($5 million) and improving sewage treatment in the U.S. and Caribbean ($10 million to $20 million).

No one expects this amount of money to be spent. The federal government this year has budgeted $500,000 to $800,000 for protecting corals but Moore said not all the money will come from the federal government.

Coral grows extremely slowly and some of the living coral reef structures off the southeast Florida coast are hundreds of years old.

“The recovery team estimated that it will take approximately 400 years to achieve recovery based on the significant mitigative actions identified in this plan,” the plan states.

The Center for Biological Diversity, which originally petitioned the federal government to protect the corals, praised the proposal.

“The recovery plan makes it clear that the primary threat to elkhorn and staghorn is climate change and ocean warming and ocean acidification,” said Shaye Wolf, climate science director of the Arizona-based environmental group. “I think the strategy should be: No. 1, that the U.S. needs to take significant action to slow climate change, and No. 2, we need to reduce significant threats to corals while we work on the climate problem.”

The next step for the fisheries service will be to set up implementation teams of governmental and environmental representatives, outside scientists and others with knowledge of the reefs. These teams, expected to be in place by September, should also be a means of leveraging money from other agencies, state and local governments and non-profits, Moore said.

Meanwhile, the federal government is working on regulations to protect another 20 coral species found in the Pacific and Atlantic oceans. Of these, five are found in South Florida, including pillar coral, rough cactus coral, lobed star coral, mountainous star coral and boulder star coral.

People in the aquarium industry, including dealers, wholesalers and hobbyists, have expressed concern about the impending regulations, fearing they could shut down trade in popular species or simply make all imports more difficult, legal or not.

“This is my only income to support my family,” wrote John Welsh, owner of Reef Lovers Aquariums of West Palm Beach. “Myself and most all aquarium professionals love the ocean and all its creatures and would do anything to preserve it for my family and future generations. The 20 corals that are listed, I am sure, have shown a significant decrease but that is not from over collecting for the aquarium trade. I am sure there are many other large contributors to the decline in these species.”

Moore said the government may not ban the trade in these species.

“Trade is really among the lowest of our concerns,” she said. “The threshold is whether it’s necessary for the conservation of the species.”