After 140 Million Years, Chinese Sturgeons May Soon Be Extinct
By Jason Bittel
More than 16 feet long and weighing up to 1,100 pounds, Chinese sturgeons are among the world's largest freshwater fish. They're big and they're ancient. According to fossil records, they've been swimming China's Yangtze, Qiantang, Minjiang and Pearl Rivers since the time of the dinosaurs.
And now they're on the brink of oblivion, having disappeared from all of their former range except for small portions of the Yangtze.
Over the millennia, humans have sought out these freshwater leviathans not so much for their flesh as for the thousands of tiny black pearls that can be found within the adult females—in other words, caviar.
China began regulating sturgeon fishing in the 1970s, when the full breeding population had been whittled down to just 10,000 individuals. The move saved the species from extinction, but alas, in recent decades an even more existential threat has cropped up.
Dams. So many dams.
Chinese sturgeons are what's known as anadromous fish. Like salmon, they spend part of the year in the ocean and part of the year plying freshwater rivers and streams on the way to their ancestral breeding grounds. But unlike salmon, Chinese sturgeon don't die after spawning. Instead, after they mix up their DNA through an exchange of sperm and eggs in shallow waters upriver, they beat fin back to the sea. Under normal conditions, a Chinese sturgeon can live up to 20 years—spawning again and again and again.
Now, imagine you're a huge fish that's been swimming up a river for a decade and change, just like your anfishestors have for millions of years, and one day you run into a concrete wall.
That's what happened to Chinese sturgeon in 1981 when the Gezhouba Dam began operating on the upper reaches of the Yangtze River. The dam shortened the sturgeon's annual migration by 730 miles. Amazingly though, the fish still managed to breed. Well, somewhat. According to a study published in Current Biology this month, the reproductive output of the local population dropped by more than 75 percent after the dam was in place.
But the sturgeon swam on, making do with their new, shortened home range, since scientists at the time decided there was no good reason to install a device that would allow for fish passage.
Then in 2003, the Three Gorges Dam was stretched across the Yangtze, again with no fish passage device. And then in 2012, the Xiangjiaba Dam went up, followed by the Xiluodu Dam the very next year.
As each new structure divided the river into ever smaller sections, the Chinese sturgeon population flatlined. Their current annual rate of reproduction is now estimated at between 4.5 percent and zero.
The walls themselves aren't the only problem the dams bring for the fish. Dams create large reservoirs of water behind them that soak up heat from the sun. This creates layers of varying water temperatures within the river, similar to a really big lake, says Stephanie Januchowski-Hartley, an environmental biologist at Swansea University in Wales who studies the ecological impact of dams. (Januchowski-Hartley was not part of the study.)
When the dams discharge these reserves, they can have an enormous effect on water temperatures downstream. Numerous factors come into play, such as which depth layer of water is discharged and at what time of year, but in the end, these fluctuations can muck up the sturgeon's internal workings. (Oh, and climate change isn't helping matters, according to the paper's authors.)
"Not all fish like it hot," said Januchowski-Hartley. Not only can higher water temperatures stress out cold-water fish, but the drastic difference between what they're used to and what they're getting seems to affect the rate at which the fish's gonads mature.
Historically, the fish would have had a long, progressively colder swim in which their bodies slowly shifted into reproductive mode. But now their access to the river has been cut by so much that they're jumping right into mating without all the physiological foreplay they've evolved to require. And it just isn't working. According to the new paper, there may be just 156 mature fish left in all of the Yangtze River.
The Chinese government invested heavily in repopulating the Yangtze with more than nine million sturgeon fry, or juveniles, between 1983 and 2007, but scarcely any survived. The researchers refer to these efforts as "inadequate and unsustainable" because the government kept adding new fish but did nothing to enable those fish to reproduce.
No one expects that any of these dams are going to come down anytime soon. But there is still a modicum of hope for returning the fish's spawning habitat to a proper breeding temperature. For example, dam managers could selectively release water from the reservoir that is an agreeable temperature for life downstream, or perhaps churn up the standing water in a way that mixes the layers of different temperatures. Leaving tributaries that pour into the Yangtze undammed could also help keep the temperature steady. Studies have shown that in areas just below a confluence with an undammed tributary, sturgeon spawn better and insects are more prevalent, which suggests that naturally flowing tributaries can create pockets of suitable habitat for all kinds of wildlife.
All these strategies fall into creating what's called an environmental flow, says Januchowski-Hartley, but she has doubts they'll be enough to save the sturgeon over the long term.
But something needs to be done—and quick. If not, the study's authors predict the Chinese sturgeon will likely go extinct within the next 10 to 20 years. Which means that after 140 million years on this planet, the generation of Chinese sturgeon alive today would be the last.
4 Exciting Dam-Removal Projects to Watch @lakotalaw @Youthvgov https://t.co/GjYizM9pOR— EcoWatch (@EcoWatch)1539943335.0
By Victoria Masterson
Using one of the world's problems to solve another is the philosophy behind a Norwegian start-up's mission to develop affordable housing from 100% recycled plastic.
Sustainable Homes<p>UN-Habitat says an <a href="https://unhabitat.org/un-habitat-aims-to-use-plastic-waste-to-support-housing-for-all" target="_blank">estimated 60% of people living in urban areas of Africa are in informal settlements</a>. At the same time, between 1990 and 2017, African countries imported around 230 metric tonnes of plastic, "which mostly ended up in dump sites creating a massive environmental challenge," the agency adds.</p><p>UN-Habitat deputy executive director, Victor Kisob, said the aim of the partnership with Othalo was to "promote adequate, sustainable and affordable housing for all."</p>
Artist's impression of an Othalo community, imagined by architect Julien De Smedt. Othalo<p>Othalo's process involves shredding plastic waste and mixing it with other elements, including non-flammable materials. Components are used to build up to four floors, with a home of 60 square metres using eight tons of recycled plastic. A factory with one production line can produce 2,800 housing units annually.</p><p>Following successful laboratory tests, Othalo's factory in Estonia has started producing components to build three demonstration homes for Kenya's capital, Nairobi; Yaoundé, the capital of Cameroon and Dakar, the capital of Senegal.</p><p>Othalo founder Frank Cato Lahti has been developing and testing the technology since 2016 in partnership with <a href="https://www.sintef.no/en/" target="_blank">SINTEF</a>, a 70-year-old independent research organization in Trondheim, Norway, and experts at Norway's <a href="https://en.uit.no/startsida" target="_blank" rel="noopener noreferrer">University of Tromsø</a>.</p>
Othalo founder Frank Cato Lahti. Othalo<p>Almost <a href="https://www.un.org/development/desa/publications/2018-revision-of-world-urbanization-prospects.html" target="_blank">seven out of every 10 people in the world are expected to live in urban areas by 2050</a>. More than 90% of this growth will take place in Africa, Asia, Latin America, and the Caribbean.</p><p>"In the absence of effective urban planning, the consequences of this rapid urbanization will be dramatic," UN-Habitat warns.</p><p>Lack of proper housing and growth of slums, inadequate and outdated infrastructure, escalating poverty and unemployment, and pollution and health issues, are just some of the effects.</p><p>Mindsets, policies, and approaches towards urbanization need to change for the growth of cities and urban areas to be turned into opportunities that will leave nobody behind, UN-Habitat says.</p>
Pioneers of Change<p>Reimagining cities and communities for greater resilience and sustainability was a key topic at the<a href="https://www.weforum.org/events/pioneers-of-change-summit-2020" target="_blank"> World Economic Forum's Pioneers of Change Summit 2020</a>.</p><p>The digital event brought together innovators and stakeholders from around the world to explore solutions to the challenges facing enterprises, governments and society.</p><p>Opening the summit, <a href="https://www.weforum.org/events/pioneers-of-change-summit-2020/sessions/opening-plenary-8f731cbc65" target="_blank">Stephan Mergenthaler, the Forum's Head of Strategic Intelligence and a member of the Executive Committee</a>, said: "We need to change the way we produce, the way we live and interact in our cities to make this transition to net-zero emissions a reality…</p><p>"And as this year has illustrated so dramatically, we need to make every effort that we keep populations healthy, if we want to avoid jeopardizing all this progress."</p><p><em>Reposted with permission from </em><em><a href="https://www.weforum.org/agenda/2020/11/un-africa-recycled-plastic-housing/" target="_blank">World Economic Forum</a>.</em><a href="https://www.ecowatch.com/r/entryeditor/2649069252#/" target="_self"></a></p>
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By Dolf Gielen and Morgan Bazilian
John Kerry helped bring the world into the Paris climate agreement and expanded America's reputation as a climate leader. That reputation is now in tatters, and President-elect Joe Biden is asking Kerry to rebuild it again – this time as U.S. climate envoy.
Energy Is at the Center of the Climate Challenge<p>The <a href="https://science2017.globalchange.gov/chapter/1/" target="_blank">effects of climate change</a> are already evident across the globe, from <a href="https://theconversation.com/100-degrees-in-siberia-5-ways-the-extreme-arctic-heat-wave-follows-a-disturbing-pattern-141442" target="_blank">extreme heat waves</a> to <a href="https://science2017.globalchange.gov/chapter/12/" target="_blank">sea level rise</a>. But while the challenge is daunting, there is hope. Solar and wind power have become the <a href="https://www.irena.org/publications/2020/Jun/Renewable-Power-Costs-in-2019" target="_blank">cheapest forms of power generation globally</a>, and technology progress and innovation continue apace to support a transition to clean energy.</p><p>In the U.S. under a Biden administration, long-term national climate legislation will depend on who controls the Senate, and that won't be clear until after two run-off elections in Georgia in January.</p><p>But there is no shortage of <a href="https://www.bloomberg.com/features/2020-biden-climate-change-advice/" target="_blank">ideas for ways Biden</a> could still take action even if his proposals are blocked in Congress. For example, he could use executive orders and direct government agencies to tighten regulations on greenhouse gas emissions; increase research and development in clean energy technologies; and empower states to exceed national standards, <a href="https://www.reuters.com/article/us-autos-emissions-california/defying-trump-california-locks-in-vehicle-emission-deals-with-major-automakers-idUSKCN25D2CH" target="_blank" rel="noopener noreferrer">as California did in the past with auto emission standards</a>. A focus on a just and equitable transition for communities and people affected by the decline of fossil fuels will also be key to creating a sustainable transition.</p><p>The U.S. position as the world's largest oil and gas producer and consumer creates political challenges for any administration. U.S. forays into European energy security are often treated with suspicion. Recently, France blocked <a href="https://www.wsj.com/articles/frances-engie-backs-out-of-u-s-lng-deal-11604435609" target="_blank">a multi-billion dollar contract</a> to buy U.S. liquefied natural gas because of concerns about limited emissions regulations in Texas.</p><p>Strengthening cooperation and partnerships with like-minded countries will be critical to bring about a transition to cleaner energy as well as sustainability in agriculture, forestry, water and other sectors of the global economy.</p>
Creating a Global Sustainable Transition<p>How the world recovers from COVID-19's economic damage could help drive a lasting shift in the global energy mix.</p><p>Nearly one-third of Europe's US$2 trillion economic relief package <a href="https://www.bloomberg.com/news/articles/2020-07-21/eu-approves-biggest-green-stimulus-in-history-with-572-billion-plan" target="_blank" rel="noopener noreferrer">involves investments that are also good for the climate</a>. The European Union is also strengthening its 2030 climate targets, though each country's energy and climate plans will be critical for successfully implementing them. The <a href="https://joebiden.com/clean-energy/" target="_blank" rel="noopener noreferrer">Biden plan</a> – including a $2 trillion commitment to developing sustainable energy and infrastructure – is aligned with a global energy transition, but its implementation is also uncertain.</p><p>Once Biden takes office, Kerry will be joining ongoing <a href="https://www.un.org/en/conferences/energy2021/about#:%7E:text=The%20overarching%20goal%20of%20the,2030%20Agenda%20for%20Sustainable%20Development.&text=Accelerate%20delivery%20of%20United%20Nations,related%20issues%20at%20all%20levels." target="_blank" rel="noopener noreferrer">high-level discussions on the energy transition</a> at the U.N. General Assembly and other gatherings of international leaders. With the U.S. no longer obstructing work on climate issues, the G-7 and G-20 have more potential for progress on energy and climate.</p><p>Lots of technical details still need to be worked out, including international trade frameworks and standards that can help countries lower greenhouse gas emissions enough to keep global warming in check. <a href="https://www.carbonpricingleadership.org/what" target="_blank" rel="noopener noreferrer">Carbon pricing</a> and <a href="https://www.csis.org/analysis/how-can-europe-get-carbon-border-adjustment-right" target="_blank" rel="noopener noreferrer">carbon border adjustment taxes</a>, which create incentive for companies to reduce emissions, may be part of it. A consistent and comprehensive set of national energy transition plans will also be needed.</p><p>The global shift to <a href="https://www.irena.org/publications/2019/Jan/A-New-World-The-Geopolitics-of-the-Energy-Transformation" target="_blank">clean energy will also have geopolitical implications for countries and regions</a>, and this will have a profound impact on wider international relations. Kerry, with his experience as secretary of state in the Obama administration, and Biden's plan to make the climate envoy position part of the National Security Council, may help mend these relations. In doing so, the U.S. may again join the wider community of countries willing to lead.</p>
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By Maria Caffrey
As we approach the holidays I, like most people, have been reflecting on everything 2020 has given us (or taken away) while starting to look ahead to 2021.