A man wearing scuba diving gear operates an underwater scooter amid floodwaters in Saint Mark's Square in Venice on Dec. 3. Floodwaters rose to 136 centimetres above sea level and covered over fifty percent of St. Mark's Square, Reuters TV recorded on Friday.

An underwater nursery grows staghorn coral, listed as threatened under the U.S. Endangered Species Act, at a site in the Florida Keys. Julian Sprung, a marine biologist, cleans algae to prevent the release of toxins that prohibit growth. Above him and the concrete coral garden are broken pieces of staghorn coral growing on lines, waiting for the right moment to be planted on a reef. The work is undertaken by the Coral Restoration Foundation, which restores coral to the depleted reefs off of Key Largo.

A hogfish swims past Pedro Riera, a volunteer from the Florida Marine Aquarium Society, as he cleans algae from staghorn coral in the underwater nursery in 30 feet of water. Riera says of cleaning coral, "It was great, I have an aquarium at home so it was like my own corals at home … it was fun to see my new friends as well, all kinds of various fish picking at the algae as it came loose. But being out there in the world it was much bigger with a lot more water."

A staghorn coral only a few centimeters long is planted on Molasses Reef with marine epoxy.

Volunteers from the Florida Marine Aquarium Society and locals work with Ken Nedimyer, the founder of the Coral Restoration Foundation, as he ties broken coral to a line for optimal growth.