While a new disease eliminates Caribbean coral, scientists are demolishing reefs to halt the spread

ST THOMAS, Virgin Islands / NEW YORK (Reuters) – Off the US Virgin Islands off the coast of St. Thomas, a group of scientists destroyed a reef in an attempt to save some of its coral.

They are battling a deadly and rapidly evolving disease that, according to researchers, is unprecedented in that it can damage a lot of coral species in the Caribbean Sea.

Breaking their cardinal rule to never touch the coral, scientists take sick specimens to try to prevent the spread of the disease and keep what remains.

Meanwhile, researchers and divers in Florida, where the disease was first detected in 2014, also take samples of corals and ship them to places as far apart as Kansas and Oklahoma, in the ultimate goal of saving 20 species or more. be sensitive to what has been dubbed the disease of coral tissue loss.

The disease causes a rapid loss of tissue, appearing first as white patches that spread over the coral, before stripping it completely of color and life.

About half of the coral reefs that make up Florida's reefs and about one-third of those in the Caribbean are vulnerable to the disease, at a time when fragile ecosystems are already threatened by climate change.

Overall, the Florida Upper Keys lost more than 40% of the coral cover between 2013 and 2018, according to the Florida Fish and Wildlife Commission.

Coral tissue loss stony tmsnrt.rs/2nfybsM has been identified in seven other localities in the Caribbean, according to the Florida Sea Grant, a federally funded university program. Unlike the more well-known coral bleaching phenomenon, coral usually can not recover from a disease related to the loss of coral tissue. The species are victims at different rates, with a mortality rate of 66 to 100%.

"I've never seen anything that affects so many species, so quickly and so viciously – and it's going on," said Marilyn Brandt of the University of the Virgin Islands, one of the researchers involved in the reef conservation efforts near St. Thomas.

"All the diseases I studied in the past could be considered as flu. They come every year, seasonally, and sometimes the epidemics are worse. This thing is more like Ebola. It's a killer and we do not know how to stop it. "

Brandt's team first spotted the disease on the west coast of St. Thomas in January and launched a frenzied effort to curb its advance, using the removal of sick corals with a hammer and chisel to try to save the rest.

"The coral liquefies essentially from the inside to the outside," said Brandt.

Weakened system

The disease was identified for the first time near Miami, Florida, where the port was conducting a dredging project. It has now spread to almost all areas of the state's reefs.

Corals in the area were already stressed by dredging and recent bleaching. It was not surprising that they were struck by an illness, the scientists told Reuters. As with the human body, a weakened immune system can make corals more vulnerable to disease.

"We tend to just study these events. We watch them. We try to find what to do. We are just looking at that and assuming that Mother Nature will be able to take the reins and that everything will be fine, "said Maurizio Martinelli, coordinator of coral diseases at the Florida Sea Grant.

But the magnitude of the new disease has led to a more urgent approach. According to scientists' estimates, the large corals that scientists believe to be hundreds of years old are dying in a few weeks.

"We can not just watch these corals die all before us," said Martinelli.

Corals, which cover about 1% of the Earth's surface, are animals that settle at the bottom of the ocean and support more marine life than any other marine environment. In addition to supporting thousands of species of plants, fish and other marine species, they attract a considerable number of tourists, scientists and divers.

They also provide a natural barrier to flooding, saving $ 1.8 billion in damage to buildings, businesses and coastal economies and protecting more than 18,000 citizens each year in the United States, according to the report. a 2019 report from the US Geological Survey.

But the federal budget for protecting coral reefs has not changed much in years. Coral science remains in the Middle Ages, said coral scientist William Precht.

This disease is probably the deadliest for corals since the appearance of the "white band disease" in the 1970s, destroying almost two types of coral, he said.

"We are now looking at a similar type of disease, but instead of affecting two species, there are 22," Precht said.

"The end result could be catastrophic."