Frog. (Andre Lima, AFP)

The Pretoria zoo is going to start a breeding programme with 10 critically endangered Pickersgill’s Reed Frogs to help save them from extinction, Beeld reported on Friday.

A special “frog room” had been equipped for the six-month project, the zoo’s reptile expert Mike Adams told the newspaper

According to Beeld, the small, yellow-green frogs, are smaller than a man’s thumb and are endemic to South Africa, but are found in only 18 small habitats.

“Because they are so small, conservation has been difficult,” the newspaper quoted Adams as saying.

The Johannesburg Zoo had caught 40 of the frogs, of which 10 had been moved to Pretoria.

“No one knows at this point how to breed the frogs, so with these 10 we hope to write a breeding manual so that the programme can be replicated elsewhere,” Adams said.

Pretoria zoo spokesperson Angeline Schwan said amphibians were among the most endangered species on earth.

“There are about 7 000 species, of which 3 900 are threatened and 170 are apparently already extinct,” she said.

sapa

The African clawed frog was the subject of a Stanford/SFSU study that found that this species of frog was responsible for the decline or extinction of some 200 amphibian species worldwide. Brian Gatwicke/Stanford ( Brian Gatwicke )

Bay Area scientists believe they have discovered the Typhoid Mary of the frog world: a flat, feral creature that carried a deadly fungus from Africa to California’s ponds and puddles through global trading.

Genetic analysis revealed that eight of 206 African clawed frogs — caught wild or preserved in jars at the California Academy of Sciences — carried the fungal plague called chytridiomycosis, which leaves them unharmed but kills native frogs in catastrophic numbers.

An infection was detected in a frog captured in Africa in 1934, supporting the theory that the fungus thrived there before spreading worldwide. Another infected frog, still alive, was recently trapped in Golden Gate Park’s Lily Pond.

“It
The African clawed frog was the subject of a Stanford/SFSU study that found that this species of frog was responsible for the decline or extinction of some 200 amphibian species worldwide. Brian Gatwicke/Stanford ( Brian Gatwicke )
confirms our suspicions that this is one means of spread of the fungus into the environment, through frogs that were not native,” said Sherril Green, professor and chairwoman of comparative medicine at Stanford University, who collaborated on the study with San Francisco State biologist Vance Vredenburg.

The African clawed frog resembles roadkill, but it has served an important role in medicine and research. It was first brought to the United States for use as a pregnancy test in the early 20th century, when it was routinely injected with the urine of female patients. The frogs were useful because they ovulate when injected with human urine, produce eggs all year long, and were easily imported from Africa in large numbers.

Although
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the practice is now discontinued, the African frogs likely were released into the environment by hospital workers, Green said. It was a well-intended gesture — with deadly consequences.

“Today, these frog populations are often found in or near urban areas,” said Vredenburg, associate professor of biology at San Francisco State. “It’s amazing that more than a half-century after being brought to California, these frogs are still here, and they still carry this highly infectious disease.”

The African frog may not be the only culprit. A University of Michigan study also has implicated bullfrogs, farmed as a food source in South America and shipped to America.

While the urban world and wild frogs have been at odds for a long time, the fungus is particularly tough on the thin-skinned creatures.

Called Batrachochytrium dendrobatidis, or “Bd,” it kills frogs by clogging their pores, deranging their blood chemistry and causing their tiny brains to swell.

The infection has led to the recent decline or extinction of 200 frog species worldwide, from the Sierra yellow-legged frog to the exotic jewel-colored creatures that decorate calendars, postage stamps and National Geographic magazine covers.

Some species seem resistant, such as the Bay Area’s common Pacific tree frog.

But scientists have not figured out a way to transfer such resiliency to vulnerable frogs. Vaccines, a routine type of human protection, are impractical.

To determine the African frogs’ role in the spread of the disease, Stanford and San Francisco State scientists and students spent hours in the basement of the California Academy of Sciences, sorting through thousands of specimen jars filled with old frogs floating in ethanol since 1871. Swabbing DNA from the skin between the toes and around the claws, they found that of 178 frogs, five (2.8 ercent) were positive for the fungus, confirming that the fungus was present among indigenous populations in Kenya and Uganda before they were exported worldwide.

They also embarked on frog-hunting expeditions. Traps — baited with supermarket chicken — caught 28 African clawed frogs, of which three (13 percent) tested positive. One lived in Golden Gate Park.

“It was a bit of forensic detective work,” Green said. The paper is published in Thursday’s issue of the journal PLOS ONE.

The timing of the epidemic’s spread fits with their theory, Green said. “It takes decades to see the effect of what an invading species does,” she said. “We are beginning to see now what happened long ago.”

Because the frogs are widely dispersed across the globe, Green and Vredenburg said containing the epidemic is a major challenge. The well-established fungus also can spread through water, wind and feathers of birds, Green said.

The frogs’ use, sale and transport are now highly regulated in California, but the damage has been done, they said. (A pygmy version, a favorite of aquarium enthusiasts, is less hardy, so it’s not considered a threat.)

“Now we need to be cautious about other introduced species,” Vredenburg said. “There could be other animals out there that are carrying diseases that we don’t even know about yet.”

MercuryNews.com

Climate change is likely to have a significant impact on plant and animal species, a study has found

More than half of common species of plants and a third of animal species are likely to see their living space halved by 2080 on current trends of carbon emissions, a climate study said on Sunday.

Output of man-made greenhouse gases is putting Earth on track for 4°C of warming by 2100 compared with the pre-industrial 18th century, it said.

The unprecedented speed of warming will be a shock for many species, as it will badly affect the climatic range in which they can live, it warned.

Investigators from Britain’s University of East Anglia looked at 48 786 species and measured how their range would be affected according to models of carbon dioxide (CO2) emissions.

Fifty-five percent of plants and 35% of animals could see their living space halved by 2080 at current emission growth for CO2, they found. The figures take into account the species’ ability to migrate into habitat that may open up as a result of warming.

Symptoms

The species most at risk are amphibians, as well as plants and reptiles, and regions that would lose most are Sub-Saharan Africa, Central America, Amazonia and Australia, the paper said.

Lead researcher Rachel Warren said the estimates “are probably conservative” as they were based only on the impact of rising global temperatures.

Other symptoms of climate change – storms, droughts, floods and pests, for instance – would amplify the problem.

“Animals in particular may decline more as our predictions will be compounded by a loss of food from plants,” Warren said in a press release.

“There will also be a knock-on effect for humans because these species are important for things like water and air purification, flood control, nutrient cycling and eco-tourism.”

The study, published in Nature Climate Change, said there was a ray of light.

If carbon emissions peak in 2016 – and decline by 3% to 4% annually thereafter – this would limit 2100 warming to 2°C, avoiding around 60% of the projected impact from business-as-usual emissions.

Negotiations

But if the peak is delayed until 2021, emissions would have fall yearly by 6% to achieve 2°C warming, which would need a costlier effort to rein in energy use.

Alternatively, if emissions peak by 2030 and then are reduced at 5% annually to limit warming to around 2.8°C, the loss of climatic range would be reduced by 40% compared with business-as usual.

UN members have adopted the 2°C target in world climate talks, which aim to conclude a new treaty on carbon emissions by 2015 and have it ratified by 2020.

But the negotiations have been making poor progress, and the yearly rise in emissions, driven especially by the burning of coal in big developing countries, has led many scientists to conclude that warming of 3°C or 4°C is probable by century’s end.

The new study says that loss of climate range would be bound to boost the risk of species extinction.

The Nobel-winning Intergovernmental Panel on Climate Change (IPCC) has estimated that 20% – 30% of species would be at increasingly high risk of extinction if warming exceeds 2°C or 3°C above pre-industrial levels.

AFP

(shutterstock)

The thought of eating beetles, caterpillars and ants may give you the creeps, but the authors of a UN report published on Monday said the health benefits of consuming nutritious insects could help fight obesity.

More than 1 900 species of insects are eaten around the world, mainly in Africa and Asia, but people in the West generally turn their noses up at the likes of grasshoppers, termites and other crunchy fare.

The authors of the study by the forestry department, part of the UN food and agriculture organisation (FAO), said many insects contained the same amount of protein and minerals as meat and more healthy fats doctors recommend in balanced diets.

“In the West we have a cultural bias, and think that because insects come from developing countries, they cannot be good,” said scientist Arnold van Huis from Wageningen University in the Netherlands, one of the authors of the report.

Eva Muller of the FAO said restaurants in Europe were starting to offer insect-based dishes, presenting them to diners as exotic delicacies.

Danish restaurant Noma, for example, crowned the world’s best for three years running in one poll, is renowned for ingredients including ants and fermented grasshoppers.

As well as helping in the costly battle against obesity, which the World Health Organisation estimates has nearly doubled since 1980 and affects around 500 million people, the report said insect farming was likely to be less land-dependent than traditional livestock and produce fewer greenhouse gases.

It would also provide business and export opportunities for poor people in developing countries, especially women, who are often responsible for collecting insects in rural communities.

Van Huis said barriers to enjoying dishes such as bee larvae yoghurt were psychological – in a blind test carried out by his team, nine out of 10 people preferred meatballs made from roughly half meat and half mealworms to those made from meat.

– Reuters