Australia Archives - Page 4 of 5

Large Sections of Australia’s Great Reef Are Now Dead, Scientists Find

March 16, 2017 — The Great Barrier Reef in Australia has long been one of the world’s most magnificent natural wonders, so enormous it can be seen from space, so beautiful it can move visitors to tears.

But the reef, and the profusion of sea creatures living near it, are in profound trouble.

Huge sections of the Great Barrier Reef, stretching across hundreds of miles of its most pristine northern sector, were recently found to be dead, killed last year by overheated seawater. More southerly sections around the middle of the reef that barely escaped then are bleaching now, a potential precursor to another die-off that could rob some of the reef’s most visited areas of color and life.

“We didn’t expect to see this level of destruction to the Great Barrier Reef for another 30 years,” said Terry P. Hughes, director of a government-funded center for coral reef studies at James Cook University in Australia and the lead author of a paper on the reef that is being published Thursday as the cover article of the journal Nature. “In the north, I saw hundreds of reefs — literally two-thirds of the reefs were dying and are now dead.”

Read the full story at the New York Times

Bumper season for Australia’s southern scallop fishery

January 31, 2017 — It has been a lucrative season for commercial scallop operators in Bass Strait, between Victoria and Tasmania.

At the end of December, 12 vessels had hauled in $3 million worth of scallops, one of the industry’s most productive seasons in 15 years.

The fishery’s total allowable catch (TAC) was set at 3,000 tonnes, and the vessels used about 95 per cent of that quota.

Australian Fisheries Management Authority southern manager Brigid Kerrigan said the industry had had the option to land a much larger scallop catch.

How a Fish That Hatches in Coral Reefs Finds Its Way Home

December 28, 2016 — The larvae of fish that live in coral reefs are tiny, and they are not very good swimmers. They are pushed by currents away from the reefs on which they were hatched for days or weeks until they learn to swim. Then, somehow, around 60 percent of them make their way back to their birthplaces, where they spend the rest of their lives.

Scientists know that they can navigate using the position of the sun by day. But they find their way at night, too, and now researchers think they know how: They are magnetic.

Researchers studied the larvae of Doederlein’s cardinalfish, Ostorhinchus doederleini, a reef fish that grows to about five inches long. They collected specimens near One Tree Island in the Great Barrier Reef, off the northeast coast of Australia.

When the larvae hatch, currents carry them north-northwest, and experiments have shown that they consistently swim south-southeast guided by the sun back to their birthplace. But to see whether magnetic forces are also at work, the researchers tested them by using a device that creates a uniform magnetic field whose direction can be manipulated.

With the larvae in a tank surrounded by the device, the scientists turned the earth’s normal magnetic north 120 degrees clockwise. The fish followed right along, swimming in the direction the researchers steered them. The study is online in Current Biology.

Read the full story at The New York Times

Australia rejects yellowfin tuna TAC increase

November 16, 2016 — The Australian Fisheries Management Authority (AFMA) Commission said it did not support an increase in the total allowable catch (TAC) increase of yellowfin tuna proposed at a recent meeting.

The proposal, from the Tropical Tuna Management Advisory Committee (TTMAC), would have hiked the total allowable catch (TAC) over-catch allowance, enabling commercial fishermen to bring in yellowfin tuna above the current limits during the remainder of the 2016-17 season.

Read the full story at Seafood Source

Why the death of coral reefs could be devastating for millions of humans

November 10th, 2016 — Coral reefs around the globe already are facing unprecedented damage because of warmer and more acidic oceans. It’s hardly a problem affecting just the marine life that depends on them or deep-sea divers who visit them.

If carbon dioxide emissions continue to fuel the planet’s rising temperature, the widespread loss of coral reefs by 2050 could have devastating consequences for tens of millions of people, according to new research published Wednesday in the scientific journal PLOS.

To better understand where those losses would hit hardest, an international group of researchers mapped places where people most need reefs for their livelihoods, particularly for fishing and tourism, as well as for shoreline protection. The researchers combined those maps with others showing where coral reefs are most under stress from warming seas and ocean acidification.

Countries in Southeast Asia such as Indonesia, Thailand and Philippines would bear the brunt of the damage, the scientists found. So would coastal communities in western Mexico and parts of Australia, Japan and Saudi Arabia. The problem would affect countries as massive as China and as small as the tiny island nation of Nauru in the South Pacific.

Read the full story at The Washington Post

The Secret Life of Krill

October 19, 2016 — SYDNEY, Australia — On an August morning aboard the Nathaniel B. Palmer research vessel floating at the bottom of the world, Christian Reiss was listening for acoustic signals bouncing off krill, a pinkish, feathery-limbed crustacean that is the lifeblood of the Antarctic ecosystem.

It was the last month of the Southern Hemisphere winter, and conditions were good: There was no thud from sea ice pancakes bumping together to distort his tests in the clear waters of the South Shetland Islands, about 500 miles south of Cape Horn.

Dr. Reiss, an oceanographer with the National Oceanic and Atmospheric Administration, and his team were studying where krill live in winter.

Low levels of sea ice gave them access to bays that in previous winters were closed. They wanted to know if a lack of sea ice, where krill gather to feed off the algae that live on the underside, was threatening the ocean’s largest biomass. Krill form schools that can be miles long and miles deep.

Whales, sea birds, penguins, squid and seals all feed off krill. And they compete with commercial fisheries in the same waters, who sell the tiny creatures to be used as fish food or to make omega-3 fish oil for human use.

Read the full story at The New York Times

The Great Barrier Reef is not actually dead, but it is in serious trouble

October 17, 2016 — There is a big difference between dead and dying.

Outside Magazine published a somewhat tongue-in-cheek obituary for the Great Barrier Reef earlier this week, citing its lifespan from 25 million BC-2016. The article detailed the life of the reef, its active membership in the ecological community, its worldwide fame and the coral bleaching that has led to its deteriorating health. “The Great Barrier Reef of Australia passed away in 2016 after a long illness. It was 25 million years old,” read the article.

Immediate response on social media

The obituary was met with horror and disbelief, both by scientists and social media users alike. Russell Brainard, chief of the Coral Reef Ecosystem Program at NOAA’s Pacific Islands Fisheries Science Center, told HuffPost that he believes the article was highlighting the urgency of the situation, but that those who don’t have any context “are going to take it at face value that the Great Barrier Reef is dead.”

Many people on social media are indeed taking it at face value. Twitter users have been grieving the loss of the reef and urging followers to pay serious attention to the consequences. Many are spreading false information entirely. Rowan Jacobsen, the writer of the obituary, is a food and environmental writer, not a scientist. But the article has led some outlets to claim that scientists have declared the reef officially dead, further spreading the exaggeration.

Read the full story at WREG

Dolphins more common in Potomac than previously thought

July 19, 2016 — A waterfront house on Virginia’s Northern Neck promised to be a getaway for Janet Mann from three decades of studying dolphins, primarily in Australia’s Shark Bay.

But the day after Mann and her husband closed on the place in Ophelia, VA, four years ago, she spied an all-too-familiar sight from the shore where the Potomac River joins the Chesapeake Bay.

“I said, ‘Oh, look, dolphins!’ And then I thought, ‘Oh, no,’” Mann recalled. “I think we’ve given up on getting me away from my work.”

A professor of biology and psychology at Georgetown University in the District of Columbia, Mann has since embraced the Potomac as the next frontier for her research. In fact, she’s turned that riverfront retreat into a field station for observing a surprising number of bottlenose dolphins that venture up the Bay’s second largest tributary every summer.

Though dolphins have been spotted occasionally in the Potomac for at least the last six years, Mann said she hasn’t met anyone outside of those who live near her summer house who realize how many of the marine mammals are visiting on a regular basis. Last year, she and her research team of students and other Georgetown faculty tallied nearly 200 different animals in just a two-week span.

Read the full story at the Bay Journal

Australia’s Answer to Invasive Carp: Unprotected Group Sex (For the Fish)

June 15, 2016 — Australia has a plan to rid its waterways of a destructive fish species by making the fish their own worst enemies.

The targets are European carp, also known as koi: toothless, mud-sucking, bottom-dwelling fish that breed like crazy, destroy the habitat of other species and go unchecked by native predators. And the weapon is a dose of venereal disease.

The carp got loose accidentally in the 1960s, released from farm dams. Their habit of stirring up tons of silt as they foraged for food turned the once-clear Murray and Darling Rivers murky, cutting the sunlight for aquatic plants and preventing some native fish from spotting prey. These days the rivers seethe with the highly adaptable carp, which make up as much as 90 percent of the fish biomass in the river systems.

Now scientists are turning to a virus, Cyprinid Herpesvirus 3, that they hope will kill all the carp but spare other species. The government has allocated $11 million in grant money to test the idea.

European carp spread herpes when they mate, but not quite the way mammals do. The fish jostle and bump one another in a swirling tight-knit mass as the females lay eggs that are fertilized by males. The skin-grazing frenzy leaves carp susceptible to infection.

Read the full story at The New York Times

Squid Are Thriving While Fish Decline

May 24, 2016 — The squids are all right — as are their cephalopod cousins the cuttlefish and octopus.

In the same waters where fish have faced serious declines, the tentacled trio is thriving, according to a study published Monday.

“Cephalopods have increased in the world’s oceans over the last six decades,” Zoë Doubleday, a marine ecologist from the University of Adelaide in Australia, and lead author of the study, said in an email. “Our results suggest that something is going on in the marine environment on a large scale, which is advantageous to cephalopods.”

Read the full story at the New York Times