Scientists say climate change wiped out an entire underwater ecosystem.

A frenzy of rabbit fish feeding on kelp transplanted by a University of New South Wales-led team of researchers off the coast of New South Wales in eastern Australia. (Image: Adriana Vergés) We’ve heard a lot lately about the destruction of tropical coral reefs brought on by a warming climate. And that’s a big deal — corals are the lynchpin of entire undersea ecosystems. When they go, the damage reverberates widely and ultimately, even people pay the price.

But something similar has been happening to corals’ more temperate cousins in many locations: Forests of kelp. These swaying seaweeds, too, anchor communities of diverse types of fish and other living organisms and, in turn, provide great value to humans through their contribution to fisheries. And recently, there has been some very troubling news for kelp. One forest was wiped out off the southwestern coast of Australia by extremely warm temperatures in 2011, an event that scientists called a “rapid climate-driven regime shift.” More recently, there has been massive death of giant kelp around Tasmania as well.

And now, new research in the Proceedings of the National Academy of Sciences demonstrates another way that a changing climate can devastate kelp. Adriana Vergés of the University of New South Wales in Sydney and her colleagues at institutions in Australia, Spain, and Singapore used underwater cameras to study kelp forests around the Solitary Islands, along the eastern Australian coast between Sydney and Brisbane.

This region is what Vergés calls “a famous place for being a tropical-temperate transition zone. We went there because that’s where we thought, if there’s something that is happening to the kelp, that is climate mediated, this is where it is going to be happening,” she said.

And it was. Between 2002 and 2011, all of the kelp in the 25 kilometer study area died. And the cameras showed why: They were being devoured by several species of fish, including tropical rabbitfish, that had been thriving as the temperate waters warmed up just slightly, by 0.6 degrees Celsius, during the time period. That wasn’t much, but it was apparently enough to support herbivorous fish from tropical climes that could wipe out the kelp.

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“I think what’s interesting is this realization that the greatest impacts of climate change may not be the direct effects of warming on one species, but it’s more the effects of warming on the way species interact with each other,” said Vergés. “The effect of warming on how fish eat the kelp. And it’s kind of the same with coral reef systems. Warming doesn’t kill the coral itself, it actually breaks the relationship between the coral and the symbiotic algae. It’s a case of warming impacting the way species interact.”

It’s not just the fish invading from tropical latitudes (which in the case of Australia, would be from the north). It’s also the temperature itself, which increases fish metabolism and may make them consume more, Vergés said.

What’s particularly striking about this study is that, unlike in other cases involving coral reefs or kelp forests, there was no sudden surge of warm water, sometimes called an “underwater heat wave,” that proved deadly. Instead the warm-up was slow, steady, and not even all that large in magnitude. Yet nevertheless, it seems to have shifted the conditions in which tropical fish who are herbivores and kelp forests interact, and the consequence was a total loss of kelp, at least in this particular region.

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That’s a big deal, because the study reports kelp are worth $ 10 billion to the Australian economy annually (in Australian dollars), due to their contributions to tourism and fisheries. And of course, it’s not just Australia — Japan has also seen kelp forests decimated by herbivorous fish, says Vergés, and the kelp forests off the coast of California saw major declines in abundance during the Pacific warm “blob.”

Granted, there is also some better news for kelp out there. Another new study in the Proceedings of the National Academy of Sciences found a mere 1.8 percent decline overall per year in kelp abundance over the decade. That’s because while the researchers observed major declines in some areas, they also saw expansion in others. The study suggested one thing kelp have in their favor — they can bounce back fast.


So the picture isn’t entirely grim — yet — but the individual stories of dramatic kelp wipeouts that have been dribbling in recently amid warming ocean temperatures certainly suggest reason for concern.

“They’re like the trees of the underwater world in cool water places,” said Vergés of kelp. “They provide a habitat and food for literally hundreds of species. They support an entire ecological community.”

“So when we lose the kelp, we’re losing all of that,” she continued. “They’re also one of the most productive plants on the planet, taking carbon out of the atmosphere. We lose a biological engine that controls or dominates temperate reefs.”

U.S. universities attract more than 1 million international students

The number of international students at U.S. colleges and universities topped 1 million for the first time, paced by a surge of graduate students in sciences, engineering and math from India. China still sends the most students — 328,500 or nearly a third — but enrollments from India climbed 25 percent to almost 166,000 in 2015–2016. Nikita Ankem, 23, of Nagpur, India, is pursuing a master’s in industrial engineering at Pennsylvania State University. She said a Penn State degree will be appreciated when she’s looking for a job back home. “In India, most of the education is theoretical. We’re very good in mathematics,” says Ankem, web coordinator for the Indian Graduate Student Association at Penn State. “Here you learn how to apply it all with lots of case studies, problem solving and team projects.” Saudi Arabia moved slightly ahead of South Korea to third; each sends roughly 61,000. Canada is fifth with 29,000.The figures come from Open Doors 2016, the annual census conducted by the Institute of International Education in partnership with the State Department. Its release is a highlight of International Education Week, marked with fairs and festivals at hundreds of U.S. campuses and abroad.

Bangladesh buys two submarines from China

Bangladesh took delivery on Monday of its first submarines, bought from China, as it seeks to boost its naval power in the Bay of Bengal. Bangladesh paid a reported $203 million for the two submarines, a deal which reflects the country's growing economic and defence ties with Beijing. Armed forces spokeswoman Taposhi Rabeya said they would become part of the country's naval fleet at the beginning of next year. “This is the first ever addition of submarines in Bangladesh defence force,” she told AFP. Bangladesh has been expanding its defence capabilities in recent years, building a new airbase close to neighbouring Myanmar, opening several new military cantonments across the country and adding new frigates to its naval fleet. In 2013, the government of Prime Minister Sheikh Hasina signed a billion-dollar deal with Russia to buy fighter training jets, helicopters and anti-tank missiles. Hasina announced the plan to purchase two submarines the same year as part of her government's move to build a modern navy to defend the resource-rich Bay of Bengal. A UN tribunal has settled Bangladesh's long-standing maritime border disputes with neighbours Myanmar and India, paving the way for Dhaka to invite bids from multinational firms to explore for oil in the Bay. Bangladesh officials say the tribunal’s decision has ensured the country's sovereignty over 111,631 square kilometres of sea, an area nearly equal to its landmass. Xi Jinping last month became the first Chinese president in 30 years to visit Bangladesh, which has historically been more closely allied to rival regional power India.

India continuously escalating tension along LoC, WB:

RAWALPINDI: India is continuously escalating tension along the Line of Control (LoC) and Working Boundary (WB) with clear pattern, by first using small arms, then mortar fire and ultimately artillery fire.  This was stated by Director General Inter Services Public Relations (ISPR) Lt Gen Asim Saleem Bajwa while speaking in a TV programme. He said Pakistan had never initiated escalation, but whenever India showed aggression on the LoC, Pakistan always responded in a befitting manner. DG  ISPR said violations were started during the United Nations General Assembly (UNGA) session in September 2016, when Prime Minister Muhammad Nawaz Sharif was there to present Pakistan’s point of view effectively. Bajwa said when India failed to control indigenous movement by Kashmiri youth, it staged a drama of surgical strike’ against Pakistan, but was exposed after it could not produce any evidence. He said Indian casualties because of retaliation from Pakistan were three times higher. He said Pakistan openly announced its martyrs and acknowledged their bravery, while India always hides such killings or claimed smaller numbers.