قالب وردپرس درنا توس
Home / Science / The coral reefs in Florida are now affected by bleaching and now have mysterious diseases

The coral reefs in Florida are now affected by bleaching and now have mysterious diseases



Joey Mandara is like a babysitter at the Mote Marine Lab Coral Reef Research and Renewal Center in the Florida Keys. But instead of children, it tends to grow into thousands of baby corals that grow in large, shallow tanks called raceways.

Mote has been doing this work for five years, moving corals from embryos to adult colonies and planting them on Florida's reefs. Now, the emergence of a new, debilitating coral disease makes its work more important than ever.

In a career, Mandara says that fragments of brain coral have grown rapidly in this controlled environment.

"The brain coral consisted of eight fragments," he says. "And in the course of time, they have grown up and are now merged into each other and become a coral, which will hopefully grow up over time."

Mental Labs Science Director Erinn Muller calls this progress "our bearer of hope".

Coral reefs have problems all over the world. Coral bleaching, due in part to rising sea temperatures, has stressed reefs, weakening them and making them susceptible to disease. Now scientists in Florida are struggling to fight a mysterious disease that threatens the future of the world's third largest coral reef.

In just four years, the hitherto unknown disease has already had a dramatic impact on Florida's reefs, which stretch around 360 miles along the state's Atlantic coast. Muller says it seems to be a bacterial disease, and it's lethal to about half of the state's coral species.

"When affected, the tissue sags off the skeleton," she says. "And we see that once a coral is infected, it usually kills the entire coral, sometimes within weeks, and it does not seem to stop."

Erinn Muller is Science Director at the Mote Marine Lab in the Florida Keys. She says the lab's work to raise healthy coral is a "beacon of hope" for deeply damaged reefs. (NPR)

A "local extinction" that moves

William Precht was one of the first scientists to discover the eruption and its effects on corals. In 2014, he was commissioned by the state to oversee the health of the reefs off the Port of Miami, where a dredging project was underway. He saw the disease move from one coral spot to another.

Precht says that it is particularly deadly for the types of brain and star corals that form the basis of many reefs. In some areas, almost all of these corals are dead.

"This is essentially equivalent to a local extinction, an ecological eradication of these species on the ground," he says. "And if you walk and swim on the reefs of Miami-Dade County today, it would be a very rare chance encounter that you would see some of these three or four species."

Scientists believe that ocean currents contribute to the spread of the disease. Since its discovery, it has migrated to the north and has influenced reefs to St. Lucie Bay. It is now moving south, through the Florida Keys.

A large number of researchers are working to tackle the disease on many fronts. Some use DNA analysis to identify the pathogens involved. Muller of Mote Marine says others are looking for ways to stop the spread of the disease.

"Everything from … looks at chlorine-soaked epoxy as an antiseptic and even looks at how antibiotics interact with the disease," she says. "If it's bacterial, then antibiotics would be a way to stop it."

This outbreak is the latest in a reef system that has been stressed and affected by decades of development, poor water quality, and rising sea temperatures. After a long decline in Florida, the coral reefs were decimated, leaving too few species to successfully reproduce and rebuild the population.

For this reason, Muller believes that it is now best to breed and transplant healthy corals into the laboratory. "We're just at a critical moment when we have corals on the reef," she says. "Before we lose more coral, it's time to make a change."

Mote Marine Lab hopes to plant 35,000 of its laboratory-grown corals on the reefs of the Keys this year. So far, Muller says corals that have been raised in the lab have shown resistance to the mystery disease and give scientists hope that they may still be able to save Florida's reefs.

Copyright NPR 2018.


Source link