Just below the sea's surface off Florida's southeast coast lies a virtual gold mine.
It's not sunken treasure or a Spanish galleon but rather nature's bounty: rows of coral reefs that generate billions of dollars a year in tourism spending.
But pollution, warming waters from climate change, commercial fishing, development and ship groundings are jeopardizing them. With 84 percent of the nation's coral reefs located along Florida's 1,350 miles of coastline, officials are moving quickly to protect them.
On Thursday, Tim Keeney, the U.S. deputy assistant secretary for oceans and atmosphere and a key high-level figure within the National Oceanic and Atmospheric Administration, got a firsthand look at reef damage and repair and recovery efforts.
"Just gorgeous. That's impressive," said Michael Sole, Florida's environmental chief, who joined Keeney. He had just returned to the boat after scuba diving off Fort Lauderdale, where he viewed elkhorn and staghorn coral, recently listed as endangered species.
"Taking appropriate measures to improve our understanding is key because you can't manage what you don't understand," Sole said. "Our ocean resources pump billions of dollars into our economy."
The state is managing underwater nurseries to grow coral that will be transplanted onto natural reefs, seeking to end the pumping of treated wastewater into the ocean and plowing ahead with research into artificial reefs.
Florida is also spending $2 million to remove some 700,000 old tires from the ocean floor off Fort Lauderdale that were dumped there in the 1970s with the intent of creating an artificial reef. It didn't work, and now the tires are scouring the ocean floor and wedging against the natural reef, killing coral.
"The first thing you think when you see it is these things don't belong here. It's a wasteland," Keeney said after surveying the tires.
Scientists warn that up to half of the world's coral reefs could disappear by 2045. The reefs serve as breeding grounds for many commercial fisheries, so without them, an important food source for humans could be lost.
Reefs also serve as natural barriers to tidal surges created by powerful storms. Degrading them could put coastal communities at risk.
"We're talking about a major economic engine that people don't understand," said Richard Dodge, executive director of the National Coral Reef Institute. "They support people's incomes and livelihoods."
Reef-related activities generate more than $4 billion for the economy of southeast Florida alone, Dodge said.
Congress is considering the reauthorization of the Coral Reef Conservation Act, which would add another layer of protection for the nation's reef system, Keeney said.
Under current law, the federal government has no authority to fine boats or ships for running aground on coral reefs that are not located within marine sanctuaries or to penalize people who destroy them, he said.
"It doesn't allow us to go into areas outside protected areas and hold parties responsible for the damage," Keeney said.
Reauthorization of the act would create that authority and also build a federal fund to restore damaged reef systems, he said. States and counties currently have limited authority.
There have been 12 major ship groundings on reefs outside Port Everglades, just south of Fort Lauderdale, since 1993. The port has three reefs off its shore and narrow channels and tight spots for maneuvering among them.
As Thursday's trip neared its end, Keeney peered out over the glistening, emerald green ocean and pointed to a pod of dolphins bobbing along a reef. Several large freighters passed by in the distance, heading toward Port Everglades.
"People are just now starting to appreciate the value of reefs," Keeney said. "It takes a long, long time to grow these coral reefs and in a very short period of time, we can destroy them if we're not careful."