All Exploration

Home » Posts filed under Endangered Species

Tampilkan postingan dengan label Endangered Species. Tampilkan semua postingan

Triple threat paints grim future for frogs

Frogs, salamanders and other amphibians may eventually have no safe haven left on the globe because of a triple threat of worsening scourges, a new study predicts.

This undated handout photo provided by Christian Hof shows a marked Silverstoneia flotator. This species is currently not listed on the IUCN Red List of Threatened Species, because it is very common across its distribution which is located in Central America (mainly Costa Rica and Panama). However, according to our analyses the area where it occurs may become strongly affected by several of the major factors threatening amphibians, namely land-use change and the fungal disease chytridiomycosis. Frogs, salamanders and other amphibians have no safe haven left on the globe because of a triple threat of worsening scourges a new study predicts [Credit: AP Photo/Christian Hof]

Scientists have long known that amphibians are under attack from a killer fungus, climate change and shrinking habitat. In the study appearing online Wednesday in the journal Nature, computer models project that in about 70 years those three threats will spread, leaving no part of the world immune from one of the problems.

Frogs seem to have the most worrisome outlook, said study lead author Christian Hof of the Biodiversity and Climate Research Center in Frankfurt.

Meanwhile, federal scientists in the United States are meeting in St. Louis this week to monitor the situation and figure out how to reverse it.

Several important U.S. amphibian species - boreal toads in the Rocky Mountains and the mountain yellow legged frog in the Sierra Nevada Mountains - are shrinking in numbers, said zoologist Steve Corn, who is part of the U.S. Geological Survey's Amphibian Research and Monitoring Initiative. The western U.S. has the problem worse than the East.

About one-third of the world's amphibian species are known to be threatened with extinction, and 159 species already have disappeared, a 2008 international study found.

"It's no fun being a frog," said prominent biodiversity conservationist Stuart Pimm of Duke University, who wasn't part of Hof's study or the USGS effort. "They are getting it from all three different factors."

Hof's study was the first to look at projections of the three threats by geography and see if they overlap. While they overlap some, it's not nearly as much as expected. The wide distribution of threats leaves no refuge for amphibians.

The strongest threats seem to be where the most species of amphibians live, concentrating the potential loss of diversity, said Hof and Ross Alford, an amphibian expert at James Cook University in Australia, who wasn't part of the research.

The biggest threats are seen, mostly from climate change, to frogs and other amphibians in tropical Africa, northern South American and the Andes Mountains, areas which Hof calls "climate losers." In the northern Andes, which have the most number of frog species in the world, more than 160 frog species are at risk, he said.

Alford and other outside scientists said they thought Hof's work might be overly pessimistic. But studying the geographic distribution of amphibian threats in the future is important, they said.

Author: Seth Borenstein | Source: Associated Press [November 16, 2011]

Catching camels in the Gobi

In October 2011 Prof. Chris Walzer and Dr. Gabrielle Stalder, veterinary scientists at the Research Institute of Wildlife Ecology at the Veterinary Science University, Vienna, successfully attached GPS satellite collars to endangered wild Bactrian camels in the Mongolian desert.

Wild camel with radio transmitter [Credit: Vetmeduni Vienna/FIWI]

Their efforts are part of the long-term Gobi Research Project on wild horses, Asiatic wild asses, and other animals that make this unique environment their home.

The range of the wild Bactrian camel (Camelus ferus) has been reduced to only three locations world-wide: two in China (Lop Nuur and Taklamakan desert) and one in Mongolia (Great Gobi A Specially Protected Area).

The Great Gobi Protected Area was established in 1975 to protect a unique desert environment that is home to several rare or globally threatened mammal species, such as the wild Bactrian camel, the Gobi bear (Ursus arctos gobiensis), the snow leopard (Uncia uncia), the argali wild sheep (Ovis ammon) and the Asiatic wild ass (Equus hemionus).

However, habitat deterioration due to increasing human demand for livestock pastures and water resources, illegal hunting, and recently also a marked increase in illegal placer mining (mining valuable minerals by washing or dredging activities) in the protected area region have become a conservation concern.

“Increasing incidences of resource extraction in the area seriously jeopardize the integral protection of the camel´s and other species´ habitat,” says Chris Walzer, a senior veterinary scientist at the Research Institute of Wildlife Ecology (FIWI) of the Veterinary Science University, Vienna, who has a long-standing landscape-level commitment to conservation research in the Gobi.

The wild Bactrian camel is listed by the International Union for Conservation of Nature (IUCN) as critically endangered. About 600 animals are estimated to remain in China and between 350 and 1,950 in the Great Gobi A protected area in Mongolia.

It is difficult to estimate population size more precisely because of the remoteness and large size of the area, compounded by the inherent difficulty of estimating population size for low density “clumped” populations.

There are large knowledge gaps relating to the movement patterns, habitat use, behaviour, ecology, population dynamics, and veterinary aspects of wild camels. One tool for finding out more about where they go and how they use their habitat is the use of GPS collars. This information is important for the development of appropriate conservation strategies.

According to Chris Walzer, it is especially important to protect suspected migration routes between Mongolia and China. “But to do so, we first need to establish exactly where the camels tend to roam.”

In October 2011, Chris Walzer and Gabrielle Stalder (FIWI) and their Mongolian colleagues were able to capture andcollar four wild camels. Both scientists are highly skilled and experienced in capturing and anaesthetizing wild animals for various bio-medical procedures, which can be a tricky and even dangerous undertaking.

In this instance, the team spent two weeks living in tents and chasing after camels in 4x4 vehicles in this harsh and remote environment more than 1000 km from the capital Ulaanbaatar. Driving 250 km on bumpy roads and off-road across the stony desert can take as long as seven hours, and tracking camels in the huge area can be like finding a needle in a haystack.

It took three days before the scientists spotted a group of camels. Once they caught sight of some camels, the team had to try to get close enough to dart individual camels on the run from the jeep, without causing the animals excessive stress before anaesthesia.

Between October 2002 and June 2007, Chris Walzer and other scientists had radio-collared and monitored 7 free-ranging wild camels, but those collars are no longer operational and data from more individuals was urgently needed to reveal habitat and space use patterns. Now there are four more individuals whose GPS signal will provide essential locational data.

Prof. Walzer and Dr. Stalder were accompanied on this trip by Dr. Pamela Burger of the Institute of Population Genetics, Vetmeduni Vienna, who collected some genetic samples for the continuing analysis of relatedness between wild and domestic Bactrian camels and to help estimate the degree of hybridization inside the protected area.

The genetic analysis is a long-term collaboration between scientists at the two institutes.The FIWI scientists´ efforts to study and conserve the desert habitat of these species are undertaken in partnership with Dr. Richard Reading of the Denver Zoo, and Adiya Yamasuran of the Mongolian Academy of Sciences.

Source: University of Veterinary Medicine - Vienna [November 11, 2011]

Death of rhino species rings extinction alarm bells

Several species of rhino have been poached into extinction or to the point of no return, according to an update of the Red List of Threatened Species, the gold standard for animal and plant conservation.

The western black rhino has been officially declared extinct [Credit: AFP]

All told, a quarter of all mammal species assessed are at risk of extinction, the International Union for the Conservation of Nature (IUCN), which compiles the list, said on Thursday.

About a third of the 61,900 species now catalogued by the IUCN are classified as vulnerable, endangered, critically endangered, or extinct, with some groups, such as amphibians and reptiles, in particularly rapid decline.

Rhinoceros have been hit especially hard in recent years. Their fearsome horns -- prized for dagger handles in the Middle East and traditional medicine in East Asia -- can fetch hundreds of thousands of dollars on the black market.

The new assessment shows that a subspecies of the western black rhino (Diceros bicornis longipes) native to West Africa is now extinct, joining a long list of creatures -- from the Tasmanian tiger to the Arabian gazelle -- that no longer stride the planet.

Central Africa's northern white rhino (Ceratotherium simum cottoni) is listed as "possibly extinct in the wild", while the Javan rhino (Rhinoceros sondaicus) is making a last stand after the remaining specimen of its Vietnamese counterpart was killed by poachers last year.

"Human beings are stewards of the earth and we are responsible for protecting the species that share our environment," Simon Stuart, head of the IUCN Species Survival Commission, said in a statement.

"In the case of both the western black and the northern white rhinos the situation could have had very different results if suggested conservation measures had been implemented."

Things of myth and legend

There were a few slivers of good news showing that species can be prevented from slipping into oblivion.

The southern white rhino subspecies (Ceratotherium simum simum) is back from the brink, its numbers up from 100 at the end of the 19th century to some 20 000 today.

Central Asia's Przewalski's horse (Equus ferus), meanwhile, has moved from a status of critically endangered to endangered.

"We have the knowledge that conservation works if executed in a timely manner," said Jane Smart, the Global Species Programme director.

The general trend, however, is an acceleration in extinction across a wide spectrum of fauna and flora. Indeed, many scientists say Earth is on the edge of a so-called great extinction event, only the sixth in half-a-billion years.

Some groups are especially vulnerable. In Madagascar, home to a dazzlingly rich diversity of life, an alarming 40% of reptiles are threatened.

Plant species are disappearing too. Such was the fate of the Chinese water fir (Glyptostrobus pensilis), once common in China but now apparently extinct in the wild due to habitat loss.

The new classification also recognises new species, including 26 recently discovered amphibians such as the blessed poison frog (Ranitomeya benedicta) and the summers' poison frog (Ranitomeya summersi).

Both are threatened by habitat loss and harvesting for the international pet trade.

"The world is full of marvellous species that are rapidly moving towards becoming things of myth and legend," said the IUCN's Jean-Christophe Vie.

Source: AFP [November 08, 2011]

Conservation scientists 'unanimous' in expectations of serious loss of biological diversity

The number of species recognized as endangered is ever increasing and a new study by a University of York academic, published in Conservation Biology, reveals the unanimity among conservation scientists of expectations of a major loss of biological diversity. The survey also shows a growing acceptance of controversial strategies such as 'triage' -- a decision to prioritise resources and not to intervene to save some highly threatened species.

The WWF now estimates that biodiversity has declined by more than a quarter in the last 35 years [Credit: iStockphoto/Tammy Peluso]

"As with climate change the large level of investment needed if loss of biodiversity is to be stopped will result in an increase of public and political scrutiny of conservation science," said study author Dr. Murray Rudd from the Environment Department at the University of York. "That makes it important to show how much scientific consensus there is for both the problems and possible solutions."

583 individuals who had published papers in 19 international journals took part in Dr Rudd's survey via email. The survey sought to gather opinions on the expected geographic scope of declining biological diversity before posing 16 questions to rank levels of agreement with statements that explored authors' values, priorities, and geographic affiliation and their support of potential management actions.

"The survey posed the key questions facing conservation science: why people care, how priorities should be set, where our efforts should be concentrated and what action we can take. Scientists were also asked about a range of potentially controversial statements about conservation strategies to gauge shifting opinions," he said.

The results revealed that 99.5 per cent of responders felt that a serious loss of biological diversity is either 'likely', 'very likely', or 'virtually certain'. Agreement that loss is 'very likely' or 'virtually certain' ranged from 72.8 per cent of authors based in Western Europe to 90.9% for those in Southeast Asia.

Tropical coral ecosystems were perceived as the most seriously affected by loss of biological diversity with 88.0 per cent of respondents who were familiar with that ecosystem type gauging that a serious loss is 'very likely' or 'virtually certain'.

"When considering conservation values and priorities the scientists said understanding interactions between people and nature was a priority for maintaining ecosystems," said Rudd. "However, they largely rejected cultural or spiritual reasons as motivations for protecting biodiversity. They also rejected 'human usefulness', suggesting many do not hold utilitarian views of ecosystem services."

Respondents to this survey had more unanimity on the human role in loss of biological diversity than respondents to a recent survey on climate change. In this survey, 79.1 per cent of respondents stated that acceleration of the loss of biological diversity by human activities is virtually certain. In the other survey, by comparison, 61.9 per cent thought climate change was underway, whereas 55.1 per cent believed it to be accelerated by humans.

The respondents to Rudd's survey were also asked to consider conservation triage, when, given limited resources, a decision may be made not to intervene to save a highly threatened species. Triage has long been considered controversial among conservation scientists. Yet 50.3 per cent and 9.3 per cent of scientists agree or strongly agree that criteria for triage decisions should be established.

"Understanding the degree of consensus within the scientific community will help policy makers to interpret scientific advice, improving the likelihood of successful of conservation initiatives," concluded Rudd. "The extremely high level of consensus demonstrated by these results underlines the urgency of preventing further damage to the natural world."

Source: University of York via AlphaGalileo [November 08, 2011]

All Exploration

Triple threat paints grim future for frogs

Catching camels in the Gobi

Death of rhino species rings extinction alarm bells

Conservation scientists 'unanimous' in expectations of serious loss of biological diversity

Entri Populer

Category