Mereka Kabur

By Victoria Gill
Science and nature reporter, BBC News

They are colourful and rather charismatic geese, which chatter and squeak rather than honk.

Huge flocks of them pepper a bleak, wintry scene with flashes of orange.

But the beautiful views here on the Black Sea coast in northern Bulgaria, where thousands of red-breasted geese gather, mask the fact that the birds are in trouble.

The population of these geese has declined by 50% in the last decade. At the last count, scientists estimate that there were just 40,000 of the birds left in the wild.

That makes them the world's most endangered goose.

Colourful character: Red-breasted geese are under threat

Most of those 40,000 birds spend the winter close to the Black Sea coast, where the wheat fields make ideal feeding grounds.

But the landscape here is changing in a way that could be damaging the geese. Many of the formerly lush, green winter wheat fields are being used for more profitable crops. They are often ploughed in the winter so that vegetables or sunflowers can be sown.

"Particularly since Bulgaria joined the EU, farmers are switching to these 'cash crops'," says Peter Cranswick from the UK-based Wildfowl and Wetlands Trust (WWT).

Mr Cranswick is leading a research and rescue project in Bulgaria. The aim is to catch and attach tags to about 30 of the geese and to shed light on what is driving their decline.

"We know some of the threats that the birds face," he says.

"For example, we know that hunting is a problem. It's not that the hunters are killing a significant number of the birds, but the shots disturb the whole flock."

The wheat fields in Bulgaria make ideal winter feeding grounds for the birds

If the birds are scared away by gunfire while they are feeding, they spend enough time building up their food reserves for the long migration north, back to Russia, where they breed.

In a chilly early morning visit to a protected area around Durankulak Lake, we see hundreds of the geese flying from their roosts on the sea to the wheat fields.

Hunting is banned immediately around the lake, but in the small area we explore, there are about a dozen spent shotgun cartridges. We even find one dead red-breasted goose lying in the grass.

A dawn start affords a stunning view of the sky over Durankulak Lake

Local hunters are allowed to shoot the more common white-fronted geese, but they occasionally hit the endangered red-breasts by mistake.

This is hard to avoid, as the two species flock together. And it is even more difficult for the local authorities to police any illegal hunting of the endangered red-breasts on these open landscapes.

Cannon-netting

The WWT team is working on the tagging project with the Bulgarian Society for the Protection of Birds (BSPB).

They set out from their base in the seaside village of Tuylenovo on a dark January night - while the geese are roosting on the sea - to set a cannon-net in a nearby field.

The net, fired from a cannon, allows the scientists to retrieve the geese

"We have to disguise the net and then wait, and hope, that the geese come close enough to it," says Mr Cranswick.

The following morning, the team is expecting a long wait in a cold, damp field for the geese to wander into the catching area.

But, just two hours after their dawn stake-out begins, the geese amble into just the right spot and the researchers make the snap decision to hit the trigger.

The nets also capture the more common white-fronted geese

With a boom and a cloud of white smoke, a large net is fired over the flock, capturing about 25 birds, including six red-breasted geese.

The birds struggle a little bit at first, but eventually settle and seem to sit patiently (if somewhat confused by their inability to move) waiting for the scientists to retrieve them.

After an exhausting run of about half a mile (0.8km) across a field of the most glutinous mud I have ever negotiated, the team carefully peel back the net and remove the geese.

"We weigh and measure the birds and then the biggest male geese get the tags," Mr Cranswick explains.

Satellite backpack

It's a painstaking process to tag the birds - carefully strapping on these miniature backpacks of lightweight technology with soft, teflon straps that disappear under the feathers.

The researchers transport the geese in sacks to keep them calm

"You have to be careful to put the straps in the right place," says Mr Cranswick.

"Just like if you were wearing a backpack, if the straps were rubbing on a bony area, it would be uncomfortable."

In this catch, three of the birds are large enough (and male enough) to be tagged.

With their trackers securely in place, the birds have a rather comic little aerial protruding from their backs.

These satellite transmitters will give the scientists precise co-ordinates of the birds' whereabouts.

The team will follow the geese as they move around the wintering ground and, eventually, as they migrate north.

This should reveal which areas are important stop-off points for them and when - and hopefully why - they may be veering off course or being disturbed.

"We will get very precise information about where they are," says Mr Cranswick.

"That'll be very useful, for example, to assess the impact of hunting. If we follow individual birds, we will see if they're forced to move around more when there is hunting [activity]."

Wildlife exchange

"It's very important that we try to do what we can to stem this decline as quickly as possible," says Debbie Pain, head of conservation at the WWT.

A big part of that, she explains, is working with local communities, and especially with farmers, to make the case for these charismatic birds.

"The geese do feed on the winter wheat, so the farmers may think they're damaging their crops," she explains.

RED-BREASTED GEESE The birds roost on the sea to protect themselves from predators. On their Arctic breeding grounds, they often nest close to large birds of prey The geese have a distinctive "squeaking" call. The red-breast is the only goose listed as endangered by the International Union for the Conservation of Nature "But, because they have such sharp bills, they tend not to pull the wheat up but to cut the top off. That can cause the wheat to branch and give you a nice, strong crop." The BSPB and WWT are combining their efforts and expertise to make the case for the red-breasted goose to farmers and policy-makers in Bulgaria. The researchers are even hoping to inspire the next generation of local conservationists. Brian Morrell, , learning manager from the WWT's Caerlaverock Wetland Centre in Scotland has helped organise an exchange between children at Caerlaverock primary school and a local school in Shabla, close to Durankulak. The children exchange letters, drawings and paintings of their local wildlife. At Shabla school, an entire hallway is given over to a colourful art project dedicated to the red-breasted goose. The biggest breakthrough here though is the tagging success. "The project is very exciting as well as important," says Dr Pain. "This is the first time the birds have ever been caught in the wild. "They have their tags on now, and the information we'll get from those will tell us what the birds are doing and where they're going throughout the year - on their long migration to the breeding ground as well as here on the wintering ground. "That information will be invaluable in helping us to conserve this vulnerable species." By : Beliani Z. I

  

A wild, endangered goose chase

Bagaimana Lebah Melihat Lingkungan Sekitar di bawah Pancaran Sinar Matahari yang Kuat

How bees see world in UV

By Neil Bowdler Science reporter, BBC News

Researchers are being offered a glimpse of how bees may see flowers in all their ultra-violet (UV) glory.

The Floral Reflectance Database (FReD) was created by researchers at Imperial College London and Queen Mary, University of London.

It enables researchers to "see" plant colours through the eyes of bees and other pollinating insects.

Bees have different colour detection systems from humans, and can see in the UV spectrum.

Details of the free database are published in the open-access journal PLoS ONE.

"This research highlights that the world we see is not the physical or the 'real' world - different animals have very different senses, depending on the environment the animals operate in," said Professor Lars Chittka from Queen Mary's School of Biological and Chemical Sciences.

"Much of the coloured world that's accessible to bees and other animals with UV receptors is entirely invisible for us. In order to see that invisible part of the world, we need this special machinery."

The researchers collected what's called "spectroreflective" measurements of the petals and leaves of a large number of different plants. These measurements show the colour of plants across both the visible and invisible spectrum.

Users of the database can then calculate how these plants appear to different pollinating insects, based on studies of what different parts of the spectrum different species see.

Scientists have inferred what colours insects see by inserting microelectrodes into their photoreceptors, and by using less invasive behavioural studies.

Seeing the world as insects may see it can reveal "landing strips" which are invisible to the human eye. These act to guide insects to the nectar they feed on.

These landing strips might take the form of concentric circles of colour or dots.

"Quite often, you will find in radial symmetrical patterns that there is a central area which is differently coloured. In other flowers there are also dots in the centre which indicate where there is basically an orifice for the bee to put in its tongue to extract the goods."

Greenhouse use

Creeping Zinnia as we see it (left) and with UV shades made visible (right)

But what is the point of such a tool beyond giving researchers an insect's view?

Professor Chittka says seeing these invisible colours may have commercial applications in the greenhouse and beyond.

"Every third bite that you consume at the dinner table is the result of insect pollinators' work. In order to utilise insects for commercial pollination purposes, we need to understand how insects see flowers.

"We need to understand what kind of a light climate we need to generate in commercial glass houses to facilitate detection of flowers by bees."

Co-author Professor Vincent Savolainen, from Imperial College London, says the database also offers us new perspectives on how plant colour evolved.

"We hope this work can help biologists understand how plants have evolved in different habitats, from biodiversity hotspots in South Africa to the cold habitats of northern Europe," he says.

"FReD's global records may show how flower colour could have changed over time, and how this relates to the different insects that pollinate them, and other factors in their local environment."

By:
Beliani Z.I

Beruang Kutub Terancam Punah? Wah Gawat !!!

Polar bear 'could still be saved'

By Neil Bowdler Science reporter, BBC News

The polar bear needs ice platforms to hunt for ringed and bearded seals

Cutting global greenhouse emissions might yet save the polar bear and its Arctic habitat, according to scientists in the US.

It has been suggested that emissions of greenhouse gases have already put the Arctic ice cap and the polar bear on an irreversible path towards extinction.

But a new study suggests rapid emission cuts could help preserve ice cover to save the iconic bear.

Details are published in the academic journal Nature.

A US Geological Survey team led by Dr Steven Amstrup predicted back in 2007 that two-thirds of the world's 22,000 polar bears would disappear by half way through the next century.

This was based on industrial emissions continuing on a "business as usual" basis.

Elsewhere, a study suggested industrial emissions of greenhouse gases might have already put the world on target for temperature rises which would result in rapid and perhaps irreversible ice loss in the Arctic.

Dr Amstrup and colleagues now say that such dire forecasts might be avoided if industrial societies act quickly to cut emissions.

Key to their argument is the conclusion that there is no "tipping point" in the Arctic beyond which the battle is lost.

"In this paper we looked at what would happen if we allowed greenhouse gas emission to rise up to the level where some of these rapid ice loss events started to occur but [we] then arrested the increase in emissions at that point," Dr Amstrup told the BBC.

"What we found is if we did that, then ice didn't just continue to decline after these rapid loss events, but there was some substantial recovery and then maintenance of sea ice throughout the century."

"The good news for polar bears is we haven't crossed a tipping point beyond which polar bears and their Arctic habitat can't recover."

Positive feedback

It is thought that a retreating Arctic ice cap will allow the sun to heat the open waters created by the ice's retreat, and this in turn will accelerate the melting of the remaining ice cap, perhaps irreversibly. This effect is an example of what is termed a "positive feedback".

Polar bears will feed on anything they can find if they cannot get access to the ice

But Dr Amstrup's team found in their models that there were effects which might counter this feedback mechanism.

"There are a number of other thermodynamic factors, such as the rapid freeze that results when you go from open water to cold conditions which reappear in the Fall," he says.

"The rapid freeze tends to compensate for the effects that are working to provide these potential tipping points."

Dr Ted Maksym, of the British Antarctic Survey (Bas), said he agreed there was little evidence of "tipping points" in the Arctic.

"All the literature that has looked for a tipping point for sea ice has essentially found none. This has been drowned out a bit by the noise surrounding the 2007 minimum [for summer ice loss] and a possible 'death spiral' for Arctic sea ice."

"The suggestion that if global temperature rise is kept below 1.25 degrees that polar bears will survive is encouraging; but given current trends this is not likely to be achieved. So we are by no means out of the woods."

Professor Julian Dowdeswell of the Scott Polar Research Institute at the University of Cambridge, said such research was important, but that reality could turn out to be different - something the authors of the paper have recognised.

"To have a good physical understanding of the natural world, it's important that we do run predictive models," he said.

"But it's equally important to remember that they are only models and not reality. Usually there is an envelope of possible futures, rather than one future."

'Pizzly bears'

Should the mathematical models prove wrong, or should industrial society mot move to curb emissions, then this week's Nature journal also looks at how it may end for the polar bear.

Dr Brendan Kelly of the US National Marine Mammal Laboratory, and colleagues, write in a separate comment piece about the possibility of increased cross-breeding between the polar and grizzly bears.

A polar bear with patches of brown fur was shot by hunters in 2006 and this year, a hunter killed a polar bear thought to be the offspring of a polar-grizzly hybrid.

Dr Kelly suggests that as the ice cap melts and polar bears go ashore, the natural barrier between the bear populations will fall, and such hybrids, dubbed "pizzly bears" by some, might become more commonplace.

He and his team have found 34 possible examples of such hybridisation among sea mammals in the region. Cross-breeding between the bowhead whale and the endangered North Pacific right whale could quickly push the latter towards extinction, he warns.

"Plans must be developed immediately to monitor the genetics of Arctic animals and to deal with hybrids before current discrete populations merge and at-risk species are bred out of existence," the team write in Nature.

Alhamdulillah... Ternyata beruang kutub yang sudah langka ini masih bisa terselamatkan..

By:
Beliani Z.I

Unta : Raja Padang Pasir

Camels: The Ship of the Desert

Source: John Wiley & Sons, Inc.

Author: Janice VanCleave

Topics: Middle School, Life Science: Zoology

Camels are native to the deserts of Asia and North Africa. Two kinds of desert camels are dromedaries and Bactrians. Dromedaries have one hump and are best adapted for hot deserts. Bactrian camels, which have two humps, have adaptations for living in a cold desert. Most camels are domesticated, meaning they have been tamed so they can be used by humans. But a few Bactrian camels live in the wild in the remote grasslands of Mongolia, and some dromedaries that were taken to Australia now live wild in the outback. Domestic dromedaries are found mainly in the hot deserts of North Africa and Asia. Bactrian camels are mainly found in the cold, rocky Gobi desert in Asia.

Camels are the only animals that can carry heavy loads from place to place in the desert because they can go for long periods without eating or drinking water. A camel's hump doesn't carry water, as some believe. Instead the hump is filled with fat, which is a built-in food supply. This fat provides energy and water for the animal when food and water are scarce. When the fat is used up, the hump slumps over, but with rest and food the hump fills with fat and stands upright again.

Camels can go for weeks without a drink because they get some moisture from the food they eat and have stored as fat, and because their bodies have ways to prevent water loss. One physical adaptation a camel has for keeping water inside its body is a cavity in the camel's head. Dry air that the camel breathes in mixes with moisture in the cavity before moving through the camel's body, and moisture from the camel's breath is left in the cavity when the camel exhales. When thirsty camels do drink, they can gulp down large amounts. Some drink as much as 35 gallons (140 liters) of water at a time. Camels like clean water and may even turn down dirty water. So camels often get the first clean water drawn from a well while the thirsty people wait until the camels are finished before they drink.

A short thick layer of fur protects camels from high daytime temperatures and prevents heat from escaping quickly when temperatures drop at night. Bactrian camels live in areas that get very cold in the winter, and their thick, shaggy, winter coats keep them warm. These heavy coats are shed during the hot summer months so the camels do not overheat.

Other physical adaptations that allow camels to survive in the desert include long eyelashes to protect their eyes from sunlight and blowing sand. Their eyes also have an extra thin eyelid that the camel can see through. Their extra eyelids can be closed during a sandstorm to protect their eyes. Camels can also shut their nostrils to keep sand out of their noses, and they also have large padded hoofs that help them walk on the sand.

A camel's behavior also helps it survive in the desert. On extremely hot days, a camel stays as cool as possible by resting. A camel will lie down in any available shady place or directly face the sun so that only a small part of its body receives the sun's rays. Because their body temperatures may be lower than the air temperature, a group of camels may lie down with their bodies pressed together. Camels usually walk slowly, at a speed of about 3 miles per hour (5 km per hour), to keep from overheating. They walk by moving both legs on the same side together. This leg action produces a swaying, rocking motion much like that of a ship on water. Camels are sometimes called "ships of the desert."

Subhanallah...

Unta hebat ya....

By:
Beliani Z.I

Kerang Ajaib??? Bercahaya dan Berkilauan???

Snails flash a green alarm light

By Victoria Gill

Science and nature reporter, BBC News

Even though the shell looks opaque and yellow, the green light shines through

A humble marine snail has a unique luminescent shell that brightens its glow, say scientists.
 

The snail, Hinea brasiliana, produces flashes of green light, which scare away predators.

Its tiny "bioluminescent" body part is lodged permanently within its shell, but the shell amplifies the light, and the faint glow it produces illuminates the whole shell surface.

The findings are published in the Royal Society journal Proceedings B.

Dr Dimitri Deheyn from the Scripps Institution of Oceanography in San Diego, US, led the study.

He specialises in the study of bioluminescent organisms - living things that produce their own light.

Dr Deheyn has worked on glowing snails before, but he was intrigued by this one because, when it retracted into its opaque, yellow shell to avoid a predator, it still glowed.

"The shell actually amplifies the light - making the light source appear much bigger," he told BBC News.

Examining the bright little creature further, the research team discovered that its shell was a far more effective "light diffuser" than the best commercially available product.

"It's also colour-specific," Dr Deheyn explained. "If you shine red light through it, it doesn't work; if you shine blue light it doesn't work.

"It only works for blue-green light that the snail produces."

The team now plans to study the shell in detail, to find out how it works and possibly copy its specialised light-amplifying structure.

Double defence

As well as scaring the predator away, the scientists also think the flashy snail's bioluminescence may act as a second line of defence.

The flashes puts "the spotlight" on a persistent predators, such as a crab. This means that the creatures that prey on the crab can see it more easily.

This is a known concept in biology, called the burglar alarm hypothesis.

Dr Deheyn said: "It could be the snail's way of saying, 'hey - eat that guy - he's attacking me'."

By:
Beliani Z.I