SYDNEY, Australia — Kim Cobb, a marine scientist at the Georgia Institute of Technology, expected the coral to be damaged when she plunged into the deep blue waters off Kiritimati Island, a remote atoll near the center of the Pacific Ocean. Still, she was stunned by what she saw as she descended some 30 feet to the rim of a coral outcropping.
“The entire reef is covered with a red-brown fuzz,” Dr. Cobb said when she returned to the surface after her recent dive. “It is otherworldly. It is algae that has grown over dead coral. It was devastating.”
The damage off Kiritimati is part of a mass bleaching of coral reefs around the world, only the third on record and possibly the worst ever. Scientists believe that heat stress from multiple weather events including the latest, severe El Niño, compounded by climate change, has threatened more than a third of Earth’s coral reefs. Many may not recover

Q: How does algae kill fish and other marine life?
A: During daylight, algae produce oxygen through photosynthesis, replenishing oxygen levels in the water. But at night, the algae consume oxygen. This, coupled with the normal demand for oxygen from fish, crabs and other marine life can cause dips in dissolved oxygen in the lagoon, with the lowest levels just before dawn.
As dense clusters of fish rot, bacteria increase, further consuming oxygen in the water.
The kinds of algae blooming now are not known to be toxic. But some kinds of algae can kill fish by releasing toxins into the water. Or the shape and amount of algae particles in the water can clog up fish gills.


Q: Why is the lagoon so unhealthy?
A: The problem has been brewing for years. Decades of pollution from septic tanks, fertilizers, stormwater runoff and other sources, coupled with a "perfect storm" of drought, followed by record cold in 2010, set the stage for harsh algae blooms in 2011.
A "superbloom" of green algae that year and subsequent brown algae blooms killed some 60 percent of the lagoon's seagrass, the barometer of the estuary's ecological health. Hundreds of manatees, dolphins and pelicans also died in the wake of the blooms.


Q: Did the large water releases from Lake Okeechobee cause the current bloom?
A: No. While those water releases cause blooms in the St. Lucie River and the southern Indian River Lagoon, most of that water exits inlets before it reachesBrevard County's portion of the lagoon.
"It's not Lake Okeechobee, that's pretty much certain," said Ed Phlips, professor of algal physiology and ecology at the University of Florida. "Lake Okeechobee discharges more for the St. Lucie (River). That's a whole different ballgame down there."

The US theme park operator SeaWorld says it is ending its controversial orca breeding programme.

The decision means the orca whales currently at the parks will be "the last generation", the company said.

SeaWorld, which has 12 parks across the US, has faced heavy criticism over the alleged poor treatment of its captive orcas, also known as killer whales.
The company said the orcas would be likely to die if it released them into the wild.
"For as long as they live, the orcas at SeaWorld will stay in our parks," the company said in a Los Angeles Times op-ed.

SeaWorld has previously announced that it will phase out live orca shows.
Dramatic displays by the whales are the centrepiece of three parks operated by SeaWorld, in California, Florida and Texas.
​
The Humane Society of the United States (HSUS) worked with SeaWorld on its new policies and said the announcement signalled "that the era of captive display of orcas will end".

Animal rights group Peta told the BBC that SeaWorld should release all its orcas into sea pens or coastal sanctuaries where they can experience "the natural behaviour that they are denied" in the parks.
SeaWorld stopped capturing live marine mammals decades ago, with the majority of its 29 orcas having been born in captivity.

SeaWorld's treatment of its orcas was highlighted in the 2013 documentary Blackfish, which focused on a series of violent incidents involving an orca called Tilikum.

The film also raised questions over the ethics of breeding programmes and practices such as the separation of calves from their mothers.

Since the film was released visitor numbers have fallen at Sea World's main theme parks and its share price has halved.
​
SeaWorld described the film as inaccurate, misleading and exploitative and launched a multi-million dollar marketing campaign to rebuild its reputation.
Blackfish director Gabriela Cowperthwaite was quoted by HSUS as saying the decision to end orca breeding represented "truly meaningful change".

"A radioactive isotope linked to water from power plant cooling canals has been found in high levels in Biscayne Bay, confirming suspicions that Turkey Point’s aging canals are leaking into the nearby national park.

According to a study released Monday by Miami-Dade County Mayor Carlos Gimenez, water sampling in December and January found tritium levels up to 215 times higher than normal in ocean water. The report doesn’t address risks to the public or marine life but tritium is typically monitored as a “tracer” of nuclear power plant leaks or spills.

The study comes two weeks after a Tallahassee judge ordered the utility and the state to clean up the nuclear plant’s cooling canals after concluding that they had caused a massive underground saltwater plume to migrate west, threatening a wellfield that supplies drinking water to the Florida Keys. The judge also found the state failed to address the pollution by crafting a faulty management plan.

This latest test, critics say, raise new questions about what they’ve long suspected: That canals that began running too hot and salty the summer after FPL overhauled two reactors to produce more power could also be polluting the bay."

"With tourist season just around the corner, Florida’s beach communities would normally be preparing for a happy, healthy summer. Instead, they’re reeling from polluted water that is likely to inflict severe damage to the local economy and environment.
​
Lake Okeechobee, a large inland lake in southern Florida, is experiencing its highest water levels in nearly a century due to heavy rains that fell during the month of January. This should not be suprising, because heavy rainfall events are increasing as the planet warms. But after water levels reached a foot above normal, public officials began to worry that the excess water was putting too much stress on the lake’s aging dike. Officials then made the decision to drain the lake out toward Florida’s coasts. There was one problem: Lake Okeechobee’s waters are toxic."

A “catastrophic” outbreak of disease, not mud churned up by the $205 million “Deep Dredge” at PortMiami, killed coral in Government Cut, according to a report issued by the U.S. Army Corps of Engineers.
The two-year-long dredging raised concerns after biologists and environmentalists began documenting damage to coral and seagrass struggling in cloudy water as 5 million cubic yards of mud was barged to an offshore dumping site. Dredgers deepened the channel by more than 50 feet to make way for massive new ships sailing through an expanded Panama Canal. In September, federal wildlife managers with the National Marine Fisheries Service warned the Corps damage covered four times the area allowed under its permit.

In case you need further evidence that mankind is doing a remarkable job of destroying the planet, consider this: If we continue our ways, the world's oceans will soon be home to more plastic than fish.

That's according to a new report from the World Economic Forum and the Ellen MacArthur Foundation.

"The best research currently available estimates that there are over 150 million tonnes (165 million tons) of plastics in the ocean today," the report reads. "In a business-as-usual scenario, the ocean is expected to contain 1 tonne (1.1 tons) of plastic for every 3 tonnes of fish by 2025, and by 2050, more plastics than fish (by weight)."
​
In other words, in just 34 years, plastic trash in the ocean will outweigh all the fish in the sea.

"Plastic pollution is one of the greatest burdens to the environment. Believe it or not, enough plastic is discarded every year to circle the globe four times. Even worse, it is estimated that 50% of the plastic on this planet is used only once before being thrown away.
​
To curb the issue of plastic pollution, the city of San Francisco has just done something monumental: it has  become the first in America to ban the sale of plastic water bottles. "

If you live hundreds of miles away from the coast, it probably never occurs to you that the plastic bag or cup lid that you toss into the gutter might make its way into the Atlantic or the Pacific. But somewhere between 40,000 and 110,000 metric tons of plastic waste generated by Americans ends up in the ocean, according to a groundbreaking study published earlier this year in the journal Science.
​
It's difficult to pinpoint where all that refuse originates, and researchers think that much or most of it probably comes from the nation's densely-populated coastlines. But there's also evidence that the nation's inland waterways serve as a conduit for plastic to travel thousands of miles into the oceans.

The sunscreen that snorkelers, beachgoers and children romping in the waves lather on for protection is killing coral and reefs around the globe. And a new study finds that a single drop in a small area is all it takes for the chemicals in the lotion to mount an attack.

The study, released Tuesday, was conducted in the U.S. Virgin Islands and Hawaii several years after a chance encounter between a group of researchers on one of the Caribbean beaches, Trunk Bay, and a vendor waiting for the day’s invasion of tourists. Just wait to see what they’d leave behind, he told the scientists – “a long oil slick.” His comment sparked the idea for the research.
​
Not only did the study determine that a tiny amount of sunscreen is all it takes to begin damaging the delicate corals — the equivalent of a drop of water in a half-dozen Olympic-sized swimming pools — it documented three different ways that the ingredient oxybenzone breaks the coral down, robbing it of life-giving nutrients and turning it ghostly white.