Florida's Everglades and Madagascar's tropical forest were added Friday to a list of imperiled world heritage sites by UNESCO officials who also registered lesser threats to Peru's Machu Picchu ruins and the Galapagos Islands.
The decision by the World Heritage Committee of the United Nations Educational, Scientific and Cultural Organization, meeting in Brazil's capital, brought to 35 the number of unique cultural or environmental sites considered to be in danger.
Other spots included on the list were Georgia's Bagrati Cathedral and Gelati Monastery, and the Buganda Kingdom Tombs in Uganda.
The committee determined that the Everglades National Park, a mangrove swamp sanctuary for birds and reptiles in southeast United States, "because of serious and continuing degradation of its aquatic ecosystem."
Water inflows have been greatly reduced and pollution levels have increased to a point that marine life is dying off, it said.
It was the second time the Everglades has been inscribed on the list. The first time was between 1993 and 2007 because of hurricane damage, deviation of its water supply for encroaching urban centers, and pollution from agricultural flow-off.
Madagascar's Rainforests of Atsinanana were put on the list due to excessive illegal logging and poaching of lemurs on the island following political upheaval sparked by a March 2009 coup.
The International Union for the Conservation of Nature (IUCN), the body that advises UNESCO on world heritage sites, said the forests were home to many unique species who were under threat.
On Thursday, the committee announced it was putting the cathedral and monastery in Georgia on the list because of unauthorized reconstruction work.
The Ugandan royal tombs were added because of a devastating fire this year.
While Peru's Machu Picchu was not added to the list of sites in danger, UNESCO noted recommendations that the 15th century Incan ruins be put under close watch because of severe flooding this year.
The Galapagos Islands, located off Ecuador's coast, were removed from the list under a Brazilian demand meant to reflect progress Quito had made to preserve the archipelago, made famous by Charles Darwin's 1835 study that supported his theory of evolution.
But the IUCN criticized the move, calling it "premature."
"Threats from tourism, invasive species and overfishing are still factors and the situation in the Galapagos remains critical," said Tim Badman, who heads the IUCN's World Heritage Program.
Among the notable sites maintained on the list is Jerusalem, which was included in 1982 because of excavations threatening some of its 220 historic monuments.
Explore further: Coorong fish hedge their bets for survival