south africa

Making wind turbines safer for birds

September 18, 2024 By EarthWise Leave a Comment

There are people who oppose the installation of wind turbines for a variety of reasons. It is true that wind turbines can be dangerous to birds. Estimates are that about 250,000 birds are killed flying into wind turbines each year in the U.S.

However, this data needs to be looked at in comparison to bird deaths from flying into electrical lines (25 million), vehicles (214 million), and building glass (at least 600 million). And even these figures pale in comparison to the more than 2 billion birds killed by domestic cats each year.

Despite these facts, it would still be great if fewer birds died from flying into wind turbines. Researchers at Oregon State University are part of a team looking at reducing bird collision risks from wind turbines by painting a single blade of the turbine black.

Recent research in Norway found that painting a single turbine blade black reduced the number of bird collisions by nearly 72%. Why should this work? The hypothesis is that the black-painted blades disrupt the visual uniformity of the airspace around the turbines and makes them more noticeable to birds, which prompts avoidance behavior.

The Norwegian data is based on a relatively small sample size and the Oregon State researchers as well as others in Spain, Sweden, and South Africa are working on more rigorous and comprehensive studies.

The hope is that this rather simple strategy could make windfarms safer for birds. Unfortunately, this approach is not likely to be very effective with bats, which rely more on auditory cues rather than visual cues.

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Scientists studying impact of painting wind turbine blade black to reduce bird collisions

Photo, posted May 21, 2024, courtesy of Roy Harryman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Finding Homes For Rhinos | Earth Wise

October 6, 2023 By EarthWise Leave a Comment

Northern White Rhinos are virtually extinct; only two female individuals survive in Kenya. Southern White Rhinos also nearly vanished early in the 20th century, mostly because of excessive hunting. A surviving group of fewer than 100 animals was identified in South Africa, and ongoing conservation efforts led to the existing population of southern white rhinos, which now numbers more than 16,000.

Among the most successful conservation efforts took place at a 30-square-mile farm, Platinum Rhino, that was set up in 2009 about 100 miles southwest of Johannesburg. The owner of the farm did a great job of maintaining genetic diversity of the herd and protecting it from poachers. Eventually, it was costing $175,000 a month just for security against illegal hunters seeking rhino horns.

Faced with unsustainable expenses, the farm put the herd of 2,000 rhinos up for auction in April with a starting price of $10 million. No bidders came forward.

Fortunately, in September, the conservation group African Parks announced that it had reached a deal to take over the herd. African Parks partners with 12 countries in Africa to manage 77,000 square miles of protected areas.

The plan is to start moving the rhinos into a series of new sites in the wild starting next year. Moving the 5,000-pound animals to new locations will be complicated and expensive, costing anywhere from $1,500 to move a single rhino by land within South Africa to $50,000 for far afield air transport. African Parks is now raising funds to relocate the animals.

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Now Available: 2,000 Rhinos, Free to Good Homes With Plenty of Space

Photo, posted September 4, 2023, courtesy of Eric Huybrechts via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Captive Lion Problem | Earth Wise

September 25, 2023 By EarthWise Leave a Comment

In the 1990s, there was rapid growth in South Africa of the private wildlife industry. Large numbers of cattle, sheep, and goat ranchers replaced their domestic livestock with wild animals that wealthy hunters would pay lots of money to shoot. Lions were among the most prized targets for these people. Over time, hundreds of ranchers became involved in the business of breeding large numbers of the big cats in cages or small enclosures. Wealthy clients paid $25,000 to $40,000 to shoot a captive-bred lion – cheaper than the cost of a true wild lion hunt and much easier too. The animals were not afraid of humans and were easy to find.

By 2015, about 200 ranches held at least 8,000 captive-bred lions. Over 600 were trophy-hunted that year, generating about $16 million in trophy fees, mostly from Americans.

Journalists and conservationists exposed poor conditions on many lion farms and many other abuses. Over time, the South African government cracked down on the export of lion bones and other body parts for taxidermy, traditional Chinese medicine, and other uses. The days of captive lion breeding seemed numbered but shutting down the lucrative industry is not easy.

Wild lions in South Africa are not endangered. In fact, existing sanctuaries and preserves have as many lions as they can sustain. What to do with thousands of captive lions is a real problem. Some have suggested mass euthanasia, but that appalling idea has garnered very little support. The future of these animals still hangs in the balance and so far, there are really no truly desirable solutions in the offing.

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If South Africa Ends Lion Breeding, What to Do With Captive Cats?

Photo, posted August 21, 2011, courtesy of Leszek Leszczynski via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Paving With Plastic | Earth Wise

March 25, 2021 By EarthWise Leave a Comment

The country of Ghana has an ambitious plan to recycle and reuse as much plastic waste as it produces each year (which is over a million tons) by 2030. As part of this plan, they have started to pave roads in Accra, the capital city, with asphalt containing a slurry of used plastics – shredded and melted bags, bottles, and snack wraps. Only a quarter of Ghana’s roads are currently paved, so waste plastic has many opportunities for use in paving.

Plastic roads first appeared in India two decades ago. There are now over 60,000 miles of them in that country. Several countries have only recently built their first plastic roads including South Africa, Vietnam, Mexico, the Philippines, and the United States.

Studies have shown that roads containing waste plastic have the potential to perform as well or better than traditional roads. They can last longer, can tolerate wide temperature swings better, are stronger and more durable, and are more resistant to water damage, cracking, and potholes.

Ordinarily, asphalt for roads consists of 90 to 95% aggregate – typically some mixture of gravel, sand, and limestone – and 5 to 10% bitumen, which is a black gooey substance extracted from crude oil that binds the aggregate together. Plastic-enhanced roads replace varying amounts of the bitumen (often as little as 4-10%, but sometimes much more), with plastic that is actually a stronger binding agent.

Plastic roads reduce the amount of bitumen in roads, thereby reducing carbon emissions. The plastics are not heated enough to release gases and the roads do not appear to shed microplastics. Plastic roads will not solve the world’s plastic waste problem, but they can help by diverting lots of plastic from landfills.

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How Paving with Plastic Could Make a Dent in the Global Waste Problem

Photo, posted June 4, 2010, courtesy of Sustainable Initiatives Fund Trust via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Can We Tow Icebergs To Use Their Water? | Earth Wise

February 23, 2021 By EarthWise Leave a Comment

At any given time, there are thousands of icebergs adrift in Antarctica that are hundreds or even thousands of feet across. For at least fifty years, there has been speculation about whether such icebergs could be towed from the Antarctic to places experiencing freshwater shortages. The feasibility of such a scheme is still the subject of studies that nowadays include sophisticated computer modeling.

Places like the Persian Gulf, Cape Town, South Africa, and Perth, Australia all experience water shortages and could benefit tremendously from having a large iceberg towed to their waters.

How big an iceberg would it take to quench the thirst of a city like Cape Town? Computer models show that an iceberg 2,000 feet long and 650 feet thick could produce enough water to supply the city for more than a year. However, with water temperatures in the 60s in the area, even such a large iceberg would melt away within weeks. So, to get enough water for a year, it would require a much larger iceberg – one at least a couple of miles long.

Daunting problems include figuring out how many and what sort of ships would be required. An alternative to such giant icebergs would be finding a way to insulate the icebergs so they don’t melt as quickly, thereby allowing much smaller and more towable icebergs to be harvested.

Beyond these issues, there are the ecological issues of the effects of huge amounts of very cold fresh water affecting local marine ecosystems.

Despite a wide range of challenges, there is continued interest in the idea of using icebergs as a source of very pure fresh water. In an increasingly thirsty world, it might someday actually happen.

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Can icebergs be towed to water-starved cities?

Photo, posted November 1, 2007, courtesy of M A Felton via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Are Big Cats In Big Trouble?

January 16, 2018 By EarthWise Leave a Comment

According to researchers with the National Geographic Society’s Big Cats Initiative, cheetahs are much closer to extinction than previously thought. The research team has released a study, which was recently published in the journal PeerJ, that updates the cheetah population numbers in southern Africa, the largest of its remaining habitat.

A Giant Solar Thermal Plant For Australia

October 23, 2017 By EarthWise Leave a Comment

A project planned for sunny South Australia will be the world’s largest single solar thermal power plant when it comes on line in 2020. The Aurora Solar Energy Project will have a capacity of 150 MW, which is enough to supply 90,000 people with electricity.

A Threat to Rhinos

May 31, 2017 By EarthWise

A South African court recently overturned a national ban on the trade of rhinoceros horns – a decision that was celebrated by the country’s commercial rhino breeders but slammed by animal preservation groups. A moratorium on rhino horn trade had been in effect in South Africa since 2009.

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Help For Pangolins

November 3, 2016 By WAMC WEB

Poaching and illegal trafficking in exotic animals is a world-wide problem that most of us are aware of. What most of us are less aware of is that the most trafficked mammal in the world is the pangolin, which you may well have never even heard of.

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