Indian tigers facing extinction, because of DNA

Scientists say tigers in India could become extinct because of a lack of diversity in the DNA of the breed.

It's estimated there are now fewer than 2,000 tigers in the whole world, and experts think 60% of those are in India.
In the early 1900s there were an estimated 100,000 tigers in India alone.
Since then numbers have dwindled, mainly because they used to be hunted by British officials and Indian royalty.

Experts say trophy hunting reduced the animal's numbers from 40,000 in just 100 years.

Since then though, despite conservationists' efforts to change culture and protect the species, the numbers have continued to drop.

Loss of habitat

Prof Bruford of the Cardiff School of Biosciences has been leading the research, he said there are now several other factors that are causing the threat of extinction.

He explained that 'a loss of habitat... meaning lower population sizes, means their gene pool is no longer mixing across the subcontinent."

He said this means groups of tigers are living in very separate areas and because of human populations and changes to the landscape groups of tigers will no longer mix.

This he says causes the problem of 'inbreeding' because the tigers that are grouped together are now more likely to share the same genes.

Mr Bruford said: "This is important because tigers, like all other species, need genetic diversity to survive - especially under climate change - so what diversity remains needs to be managed properly so that the Indian tiger does not become inbred, and retains its capacity to adapt."

What future do Scotland's white-tailed eagles face?

By Stephen Moss Naturalist

Britain's biggest bird of prey was nearly knocked out of our skies for good almost a century ago.

The sight of the white-tailed eagle's impressive two-metre wingspan in our skies was eventually saved by a reintroduction scheme in Scotland.
But, even as its recovery is being hailed as a conservation success, the mighty bird may be under threat once again.
The population remains small, vulnerable and limited to just one area of the country. Will the eagles ever spread their giant wings beyond Scotland?
Island pride Widespread throughout Great Britain and Ireland since the Dark Ages, it is estimated that up to 90% of the birds were lost by the time of the Industrial Revolution.
Destruction of habitat and human persecution drove the species to extinction in the early part of the 20th Century, when the last pair nested on Skye.

Hunter in the wild

Watch sea eagle chicks in the nest
Witness one of nature's most impressive swoops
See an eaglet's faltering first flight

The bird's reintroduction to Scotland, which began almost half a century ago with an attempt to put the species back on Fair Isle has, on the face of it, been a huge success.

A recent report by the RSPB, 'Wildlife at Work', estimated that 'eagle tourism' contributes up to £5 million to the economy of the island of Mull each year.
It also brings less tangible, but equally important, benefits.
These include a sense of collective success for the island's people, a pride in seeing the eagles not just in real life but on TV programmes such as Springwatch and, most importantly perhaps, the ecological benefits such a flagship species brings to the rest of the island's wildlife.
Nor is this success confined to Mull. Skye also welcomes a steady influx of visitors wanting to see the eagles and other iconic west of Scotland species such as golden eagle, hen harrier and otter.
While the Fair Isle birds eventually dispersed without forming a sustainable population, that first release taught the teams valuable lessons.

Sea eagles can live 20-25 years in the wild

From the mid-1970s, white-tailed eagles bred from Norwegian stock were released into more suitable habitat. Sites included the uninhabited Isle of Rum in the Inner Hebrides, and in Wester Ross on the Scottish mainland.
Later, in the early 21st century, the scheme was extended to the east coast of Scotland, in Fife.
White-tailed eagles, like all large, long-lived birds of prey, breed slowly, and numbers took time to grow, during which time the project had to withstand some criticism.
Some local communities did not want the birds there at all. Conservationists persuaded islanders to give the eagles a chance and to accept that, in some cases, the potential harm the birds might cause was overstated.
There were objections from other conservationists however, who thought reintroduction schemes were somehow "not natural", or considered this particular scheme to be proceeding too slowly.
In the face of their critics, the birds not only survived, but gradually grew in numbers until they started to spread around the Western Isles.
Where next? But all this effort may be at risk of failing: the white-tailed eagle could still disappear from our skies.
One reason is the relatively low numbers. Despite the project's undoubted success, the UK population of white-tailed eagles is still only about 60 pairs, almost 40 years after the Rum reintroduction began.

Tip to talon

White-tailed or sea eagle (Haliaeetus albicilla)
Length: 80 cm
Wingspan: 2.2 m
Weight: (M) 4.3 kg (F) 5.5 kg
Diet: Fish, birds, mammals, eggs, carrion
Habitat: Seacoasts, rivers, large lakes

Although the birds are not subject to the same pressures as they were in the past, such as shooting and egg-collecting, there are still many other threats facing them.

Last month, wildfires swept the Highlands threatening nesting habitats of both the golden and white-tailed eagle.
Young, inexperienced eagles face all sorts of hazards from collision with power lines and vehicles to the continued use of poisoned bait by some land managers on the mainland which although illegal, is still widespread.
But perhaps the biggest threat to the continued survival and prosperity of white-tailed eagles in Britain is inaction.
In 2007, Natural England and the RSPB proposed a plan to release the eagles into East Anglia but resistance from local communities meant the plan did not go ahead.
Roy Dennis was warden of Fair Isle Bird Observatory when the very first birds were released and he told the BBC that an opportunity had been missed in Suffolk:
"The disappointing thing was that I think many people thought that as soon as we had twenty pairs of eagles breeding in the Hebrides the job was done. Whereas others of us felt the job is not done until we have them breeding back all the way from the Channel coast to Shetland," he said.
Could white-tailed eagles be put back into other great British wetlands? The question provokes a plethora of different reactions from those living on and managing the land.
Personally, I think my own home patch of the Somerset Levels, the site of the biggest wetland rewilding project currently underway in the UK, seems an ideal place to start.
I for one look forward to seeing this majestic bird soaring not just over the Isle of Mull, but also across Glastonbury Tor, within my lifetime.

The eagles can be seen in Hebrides: Islands on the Edge which continues of BBC One (Scotland), Monday 13 May at 2100 BST and is available on iPlayer.

The otter: return of the elusive movie star

By Stephen Moss Naturalist

Elusive otters

How can you spot an otter?
Watch otters show-off underwater
See urban otters in action

Like many other creatures at the top of the food chain, such as peregrines and sparrowhawks, otters suffered very badly from the widespread use of chemical pesticides, such as dieldrin, which drained into streams and rivers and contaminated fish stocks.

But unlike birds of prey, which breed quickly enough to replenish their populations within a couple of decades, the otter's low reproductive rate meant that its recovery was far slower.

Following bans on hunting and harmful chemicals, land management techniques were used to improve the otters' habitat and give them the best chance of survival.

Having virtually disappeared from England by the end of the 1970s, apart from the far north and west, otters can now be found across the country and also throughout much of Wales.

And they are not just confined to rural areas: the mammals are regularly seen in the centre of Newcastle-upon-Tyne, and in other towns and cities.

This is crucial because having a healthy population of a top predator such as the otter shows that the river systems themselves are in a good state.

Otters held on in Scotland in far greater numbers than elsewhere, especially the remote islands of the north and west, benefitting from being able to live in parts of the country where hunting and pesticides posed less of a problem.

By 2007, Scottish Natural Heritage reported that the otter's recovery was complete - three decades after serious falls in numbers, especially in the central and southern parts of Scotland.

The diet of the otter is 75-95% fish, though it will eat small animals and birds

Otter spotting

Otters have now been found in over 90% of the Scottish sites surveyed, with healthy populations on the Clyde in Glasgow, and also in Aberdeen and Edinburgh.

Today, some of the best places to see otters are around the coasts of Scotland especially Shetland, the Western Isles, and the Moray Firth.

These coastal animals are not sea otters - that is a separate species, found along the west coast of North America - but simply river otters that have discovered that the twice-daily movement of the tides can be very productive if you enjoy a diet of fish.

Further south, the main otter strongholds are the rivers Tyne and Tees in the northeast, the upper reaches of the Severn, and smaller rivers such as the Dart in Devon home to the Tarka Trail, a series of routes inspired by Henry Williamson's 1927 novel, Tarka the Otter.

Cautious comeback

Otters may have an extraordinary survival story so far, but they still face threats.

Like many wandering mammals, they often fall victim to collisions with motor vehicles as they cross a road to get from one part of their territory to another. At sea, they are also drowned in crab and lobster traps as they try in vain to get at the contents.

Despite the fact that it has been illegal to kill otters for more than 30 years, there are still occasional calls for a cull of otters, especially when they raid garden ponds to seize valuable koi carp, some of which are worth hundreds or even thousands of pounds.

Places to see otters

Scotland
Isles of Unst and Yell, Shetland
Kylerhea Otter Haven, Isle of Skye
Loch of the Lowes, Dunkeld
Wales
Magor Marsh, Gwent
England
Bowesfield, Tees Valley
Shapwick Heath, Somerset
Northern Ireland
Glenarm Nature Reserve, Antrim

Experts also warn that invisible threats in our waterways may still be disturbing the mammals following recent research funded by the Environment Agency that suggested hormone-disrupting chemicals could be linked to reproductive problems.

But overall, Britain's otter population is in remarkable shape, much to the delight of their admirers.

One such fan was Gavin Maxwell, the Scottish naturalist and author of the novel Ring of Bright Water, upon which the film was based.

Set around his home in the tiny village of Sandaig in the Highlands, the book was based on his extraordinary and eccentric life and passionate love of otters.

Maxwell had links to two modern naturalists, both of whom made the pilgrimage to Sandaig. The late Terry Nutkins famously went on to present the BBC series The Really Wild Show; while Sir John Lister-Kaye has set up the Aigas Field Centre for eco-tourism in the Scottish Highlands, and written many bestselling books on natural history.

In the same year as the film release of Ring of Bright Water made him a household name, Gavin Maxwell died of cancer, aged just 55.

But his love of otters lives on - not just in the book and film, but also in the otter's real-life tale of revival.

More scottish wildlife can be seen in Hebrides: Islands on the Edge which continues of BBC One (Scotland), Monday 13 May at 2100 BST and is available on iPlayer.

Why hedgehogs are not welcome in the Hebrides

By Stephen Moss Naturalist

The hedgehog is arguably one of Britain's favourite mammals and possibly our most threatened.

Since the 1940s hedgehog numbers have dropped from an estimated 30 million to fewer than one million and conservationists warn they could even be extinct in Britain by 2025.

But during the past decade hundreds of hedgehogs have been deliberately killed by official government bodies, at eye-watering costs to the taxpayer.

In the Western Isles of Scotland, the non-native hogs have a bad reputation. But are they really to blame for a decline in wading birds?

Hedgehog heaven

Discover Britain's hedgehog history
See the island of blonde hedgehogs
How can you help a hog?

Machair nightmare

The story begins almost 40 years ago, in 1974, when some hedgehogs were released into a garden on the Hebridean island of South Uist, in order to help control slugs and snails.

Here, the hedgehogs faced few of the hazards that have so reduced numbers of their mainland cousins, such as heavy traffic on trunk roads and city streets, pesticides in gardens, or predation by badgers.

No wonder they soon multiplied and spread, and within a couple of decades had a population estimated at about 5,000 individuals.

By then they had also spread to the neighbouring islands of Benbecula and North Uist, which are connected to South Uist by causeways along which the hedgehogs were able to travel.

Every spring, the sandy soils along the western side of these islands are covered with a carpet of grasses wild flowers, known as 'machair'.

Machair is home to some of the densest breeding populations of wading birds anywhere in the world; with dunlin, ringed plover, oystercatcher and redshank filling the air with their calls throughout the spring and summer months. The numbers of these birds are so high that the islands are an internationally important site for them.

When the wader population on the islands began to drop rapidly, the invading hedgehogs were soon implicated in the decline: the wader nests provided easy pickings in the form of tasty eggs.

Machair develops in wet and windy conditions

Almost 30 years after the hedgehogs were first introduced to the islands, an organisation called the Uist Wader Project was formed to launch a cull of the hedgehogs, in order to prevent the nesting waders being wiped out.

The project - a coalition between Scottish Natural Heritage, RSPB Scotland and the Scottish Government - did manage to cull about 700 hedgehogs, but this soon attracted criticism: partly because there were still so many hedgehogs remaining at large, and partly because this had reportedly cost more than £800 per hedgehog in taxpayers' money.

The biggest barrier to the continuation of the cull however was not financial, but emotional. Many people - both on the islands and elsewhere - were angry that the hedgehog, an otherwise harmless mammal, was being targeted and killed at the same time as it was disappearing from much of mainland Britain.

So in the same year as the cull began, a coalition of animal welfare organisations and charities formed Uist Hedgehog Rescue (UHR).

Tender trapping

UHR agreed that hedgehogs were causing problems to wading birds on the islands, but offered an radical alternative solution: instead of killing the animals, why not trap them and relocate them to the mainland, to help boost declining populations there?

During the next three years they relocated more than 700 hedgehogs, and once they had shown that relocation was both feasible and effective - and most importantly did not cause any problems such as the spread of disease back to the mainland population - then in February 2007 the cull was halted.

Hedgehogs thrive where traffic is absent

Instead of killing the animals, Scottish Natural Heritage began to fund the translocation project run by UHR instead. So far about 1600 hedgehogs have been safely removed from the islands and relocated elsewhere.

But what might appear to be a triumph of common sense over a knee-jerk reaction against 'illegal immigrants' may be more complicated than it looks.

In February 2010, hedgehog expert Hugh Warwick, questioned the validity of the original hypothesis. Although no one would deny that hedgehogs do take the eggs of ground-nesting birds, does that necessarily mean that the rapid decline in breeding waders has been caused by the arrival of the hedgehogs?

He suggested that other factors - including changes in farming methods and climate change - might be equally, if not more, to blame than the hedgehogs. Might the hedgehogs even have become convenient scapegoats?

Earlier this year Scottish Natural Heritage announced that it was increasing funding into research on the decline of waders on the Uists.

According to the organisation, this is specifically because there are "still a number of unanswered questions about the full extent of predation on Uist waders, and the degree to which hedgehogs are responsible."

The British Trust for Ornithology in Scotland is also involved in trying to find the root cause of the waders' decline.

With many hedgehogs still at large on the islands, and a fear that the animals are becoming more firmly established on North Uist, this investigation could not be timelier.

Worthy waders

Watch the stars of the shore in action
See little ringed plover eggs hatching
How a faked injury could save a wader's eggs

Meanwhile trapping of hedgehogs continues, and those captured are still being relocated to the mainland rather than killed.

Whether the hedgehogs are fully, or only partly, to blame for the decrease in the numbers of waders on the Hebrides, one thing is certain: the results of releasing an animal into a new environment can have massive consequences not only for our delicate ecosystems and their wildlife, but also for conservationists, scientists and taxpayers.

Almost forty years on, we still do not know the full implications of that first innocent, but ultimately misguided release.

Hebrides: Islands on the Edge begins on BBC One, Monday 6 May at 2100 BST for viewers in Scotland and is available on iPlayer.

'Big cat' Canadian lynx was on the loose in UK in 1903

By Rebecca Morelle Science reporter, BBC World Service

Isla Gladstone, a curator at the Bristol Museum, where the cat is now on display, told the BBC's Rebecca Morelle that the cat spent some time in captivity

A "big cat" was on the loose in the English countryside at the turn of the last century, scientists say.

They believe a Canadian lynx was prowling around the fields of the South West in 1903 before being shot after attacking two dogs in Devon.

Tests on the animal revealed it had probably spent some time in captivity before escaping or being set free.

The animal had been donated to Bristol Museum at the time of its death and kept in its stores for decades.

The scientists' findings are published in the journal Historical Biology.

Dr Ross Barnett, a molecular biologist from the University of Copenhagen and the University of Durham, said: "I've seen one of these cats in the wild.

"They are pretty impressive cats - they are a reasonable size, and they have lots of fluffy fur which makes them look even bigger. They have sharp claws, teeth and strong muscles."

Beast of Bodmin

From blurry photos of the Beast of Bodmin Moor in Cornwall, to reports of a lion on the loose in Essex in 2012, the UK has a long tradition of spotting big cats.

Most of these claims are dismissed as misidentifications, hoaxes or even hallucinations, but not in this case.

In 1903, the unusual cat was donated to the Bristol Museum and Art Gallery. The museum's records state that it had been shot after attacking and killing two dogs close to Newton Abbot in Devon.

Unsure of exactly what it was, the exotic beast was stuffed, its skeleton preserved, and then the remains were tucked away in the museum's stores.

More than a century later, the cat was unearthed by a scientist who thought the find might be significant.

Some of the cat's teeth were missing, which suggested that it had been in captivity at some point

An analysis of the skeleton and mounted skin revealed that the animal was a Canadian lynx, which is about two to three times the size of a domestic cat and is usually found in Canada and the northern states of the US.

The researchers found that the animal's teeth were badly decayed.

Dr Barnett said: "We think it had probably been in captivity at some point in its life.

"It had lost all of its incisors, which would have been a pretty debilitating injury for a wild cat, but not a problem for one in captivity.

"It also had massive amounts of plaque on its molars, which are indication of it not having a wild diet - something with lots of wet cat food, essentially ready-processed meat like steaks."

The researchers believe that the lynx had been in captivity for some time, but they were unable to find any records of the cat's owner.

"Was it someone's pet? Was it part of a small menagerie that was travelling through the area? There aren't really any zoos nearby where it could have escaped from," Dr Barnett said.

The team is also unsure how long the animal had been at large in Devon before it was killed.

Its decayed teeth would have limited its chances in the wild, but the lynx is an adaptable animal, and may have been able to survive by preying on small mammals.

Felicity the Puma

While many big cat sightings remain unverified, sometimes the rumours do turn out to be true, and the team believes that the Canadian lynx is the earliest recorded example of an exotic cat on the loose in the UK.

Another case relates to a live puma that was captured in Inverness-shire in 1980 and had been living in the wild for a long period of time. It was called Felicity, and placed in a zoo.

But Dr Barnett said that these cases were few and far between.

He said: "It's all very good saying you saw a lion in Essex or a tiger in Shropshire, or wherever. But it is very difficult to estimate size of a species from a distance - especially if you are unfamiliar with them.

"So I would argue for continued scepticism, unless you have a body or specimen you can analyse."

Stink bugs: the scientific battle against an insect invasion

By Jane O'Brien BBC News, Washington

Scientists are using radar and wasps in the battle against stink bugs

In today's Magazine

Millions of stink bugs are emerging from their hibernation, a sign of spring that strikes fear into the hearts of farmers across the US. Could a tiny wasp be the ultimate weapon in the battle against the foreign bug invasion?

Anybody who has dealt with an infestation of stink bugs knows what a nuisance these armoured insects can be. They cluster in the thousands and release a foul odour when squashed or threatened.

And for farmers, they can be devastating.

Unlike many insects that feed on a small group or even a single plant, the brown marmorated stink bugs, which originated in Asia, eat pretty much anything. More than a hundred different crops have been recorded in their diet so far.

The devastating effect of the bugs' appetite became apparent to farmers in 2010 when swarms destroyed fruit crops across several states in the mid-Atlantic region. The attacks cost the apple industry alone an estimated $37m (£24m).

Hunt for a killer

Matt Buffington, a research entomologist at the US Department of Agriculture (USDA), says the stink bugs arrived in the US sometime between the late 1990s and 2003 to find an "enemy-free space".

"That means it can expand its population infinitely because there is nothing keeping it in check," he says.

"Birds haven't learned to eat it - possibly because it tastes gross - and native insect predators that would normally eat something like a stink bug don't recognise it."

A Trissolcus wasp in closeup (inset) and attacking stink bug eggs laid on a leaf

The stink bug killer? A parasitoid wasp - in close-up (inset) - attacks stink bug eggs and may be the best hope for ending the bug's crop destruction

In Asia, brown marmorated stink bugs are naturally controlled by parasitoid wasps. This genus of wasp, called Trissolcus, contains around 70 different species, many of which have yet to be properly described.

These wasps could prove to be the bulwark against the invasion - but identifying the most effective type to take on the Asian stink bug in the US could take years.

That is why Dr Buffington is working at the Smithsonian's National Museum of Natural History in Washington DC, home to the National Insect Collection and its 36 million specimens. The collection offers his best chance of finding the right wasp.

Bug eat bug world

Parasitoid versus parasite? A parasitoid - such as Trissolcus wasps - eventually kills its host while parasites merely feed off it
Invasive species comprise around 40 percent of insect pests in the US
The vedalia beetle and a parasitoid fly are among the earliest examples of successful biological control
They were introduced from Australia in the late 19th Century to combat the cottony cushion scale that was devastating citrus fruit crops in California.
More recently, another small wasp has been introduced from China to help control the European corn borer

"We consider it a national treasure - there's nothing like it in the world," says Dr Buffington. "It's the single reference centre for US agriculture."

There are wasps native to the US that prey on indigenous stink bugs but are ineffective against the Asian variety.

In China and other Asian countries, stink bugs and wasps have evolved together over millions of years. Importing a Trissolcus species from Asia may be the solution.

But researchers have to be sure the same wasp will not attack other insects, such as native stink bugs that are not a threat to agriculture.

"Otherwise we could be investing millions of taxpayers' dollars in a biological control programme that is either going to be ineffective or potentially disastrous for North American agriculture," says Dr Buffington, "because we might release the wrong wasp."

Stink bugs lay batches of 25-30 eggs at a time. Female parasitoid wasps then attack the bugs' eggs by laying one of their own inside each stink bug egg. The developing wasp completely devours the embryonic stink bug before hatching.

Stink bugs are stored on sticks in the lab

To have any effect, tens of thousands of wasps would need to be released into carefully selected areas to enable them to establish numbers large enough to control stink bugs. And any release would have to be sanctioned by the USDA.

But wasps are not the only possible answer. At the USDA's Appalachian Fruit Research Station in West Virginia, researchers are learning about the stink bugs themselves in the hope of developing other natural controls.

"There isn't a single solution," says Tracy Leskey, head of the stink bug task force, an alliance of government agencies and university scientists.

"First we have to understand the basic behaviour of the stink bug, its biology and ecology. We need to know what plants it feeds on and how far it can move."

Know your enemy

To measure the insects' flight range, stink bugs are tethered to miniature windmills that revolve as they fly. By counting the laps, Dr Leskey's team have discovered that most cover a distance of one to two miles - but that some can travel more than 20.

"We call them super-fliers," she says.

scientist using a radar device in an orchard

A scientist uses radar to track stink bugs' flight across an orchard

Stink bugs are also monitored by radar using miniscule radio transmitters that are glued onto their backs. That data will help scientists track the food they eat.

Experts say pesticides are not a sustainable solution because the problem is so widespread. In the last decade or so, brown marmorated stinkbugs have established themselves on the east and west coasts of the country. And although they do not harm people, they can be a nuisance - hundreds of thousands can congregate in warm houses to hibernate through the winter.

"We're still trying to work out why they do that, what attracts them," says Dr Leskey.

Insects recognise each other using chemical markers and it is possible that areas laced with pheromones may keep stink bugs away from crops. Other options might include tempting them away with other tasty plants.

Whatever the solution, researchers know they have to act fast. The 2010 stink bug invasion was the worst on record. But stink bugs have already been found earlier than usual in Maryland - and 2013 could be another bad year for farmers.

Why do 'single' birds dance?

By Jeremy Coles Reporter, BBC Nature

Red crowned crane dancing and displaying wings

The red crowned crane throws some spectacular shapes

"Mesmerising and with a little bit of mystery about it."

That is how aviculturist Amy King describes the graceful leaping, bowing, running, spinning and grass-tossing of dancing cranes.

This unique and spectacular behaviour has been imitated in various human cultures since the Stone Age and the purpose of such elaborate displays is widely understood to establish and reaffirm long-term pair bonds.

But on the occasion that young or single birds dance, for no clear social reasons, scientists become really intrigued.

Curiously, all species of crane dance throughout the year and at any age. The behaviour can appear random at times: sparked by a feather, stick or gust of wind.

The wildlife school of dance

Watch cranes reaffirm bonds through dance
See a 'superb' sound and light show
Why dance a watery waltz in perfect harmony?

Explanations for this peculiar propensity for dance have included socialisation and pair bonding in sub-adults, averting aggression and as a displacement activity when nervous.

But while these reasons could drive certain situations, they cannot explain everything.

Cranes dance most often when relaxed and at ease, often while not involved in any obvious social activity and when they are too young to form pairs; they will even dance alone.

According to a publication in The International Journal of Avian Science (IBIS) the answer could be that most crane dances, outside of courtship, are for play

Five rules

"What came as a surprise was that nobody has figured it out before," author Dr Vladimir Dinets from Louisiana State University, US told BBC Nature.

To better understand the behaviour, Dr Dinets compared non-courtship crane dances to five criteria for determining what exactly constitutes play.

These categories, widely accepted by scientists, were proposed by Professor Gordon Burghardt at the University of Tennessee in his book The Genesis of Animal Play, published in 2005.

According to Prof Burghardt, play is a repeated behaviour that should not contribute to survival, it is spontaneous and voluntary; performed when the animal is healthy and free from stress.

"They have become kind of a golden standard," Dr Dinets said, "We know that play has evolved independently in many groups of animals, from mammals to octopuses, and that its occurrence correlates with complex and flexible behaviour."

"[Play] could be a unique window into the evolution of complex behaviour, but so far we don't know even the most basic things about it," he said.

“Start Quote

[Play] could be a unique window into the evolution of complex behaviour, but so far we don't know even the most basic things about it”

End Quote Dr Vladimir Dinets

Serious playtime

Professor Burghardt describes play as a "behaviour that doesn't seem to be very adaptive or functional in the context in which you see it."

And for a long time it was thought that play was only found in mammals and a few birds.

"It is probably much more common than people think," said Prof Burghardt.

So why do animals play? There is no simple answer according to the expert: "It's a behaviour that has arisen evolutionarily many times for different reasons and many different functions."

"Like practicing skills that [the young] will need in adulthood and helping them cognitively."

For many species you only see play in young animals. There are exceptions: monkeys, apes, humans, wild dogs and turtles for example, where older animals play too.

Prof Burghardt explained that it is also more likely in animals where there is a period of parental care, where the young are protected from doing things seriously on their own to survive.

"That's why you find play much more often in mammals and birds," he said.

Keeping it interesting

Crane comeback

See how common cranes have found their way back to the UK

Dancing cranes interested Prof Burghardt because adult birds, and not just chicks, exhibit this play behaviour.

"Maybe one of the functions in cranes is that it helps keep the [long-term] pair bond exciting and interesting," he said.

For Dr Dinets, "it solves the old mystery of what crane dances are, but since play is so mysterious, it just replaces one riddle with another."

Common cranes have now returned to parts of the UK, notably Norfolk, after a 400-year absence.

Other key places to see the spectacular performances are the Somerset levels and moors, where the Great Crane Project have been releasing captive bred birds since 2010.

If you are thinking about watching the dance of these distinctive birds then the project's Amy King suggests dawn and dusk on a windy day when the birds "leap in the air and spin around, run and jump".

"[It] looks like they are having fun," she said.

UK's rare spring butterflies make a late show

Threatened pearl-bordered fritillaries finally emerged at the end of April

The UK's spring butterflies are being welcomed by enthusiasts, but weeks later than they usually arrive.

The second-coldest March on record contributed to the delayed emergence of many rare species, according to the charity Butterfly Conservation.

"First sightings" recorded by the public showed the insects typically appeared a fortnight later than normal.

One rare species - the grizzled skipper - emerged a month later than last year.

Butterfly bounty

See Britain's beautiful butterflies in slow motion
Watch an orange-tip emerge from its chrysalis
Meet the gatekeeper of the hedgerows

The pearl-bordered fritillary was another rare butterfly to make a late show. Last year the insects were first spotted on 1 April but were not recorded until 27 April this year.

Threatened wood whites could be seen by 10 April last year, but this year were delayed until early May.

And the Duke of Burgundy butterfly made an appearance in late April this spring, around three weeks later than last year.

Last spring saw butterflies emerging earlier than normal following an unusually mild February and March. But the extreme wet weather that followed resulted in a terrible year for most species.

Butterfly Conservation's findings, which focus on the UK's rare and threatened species, show a large contrast with last years' spring sightings.

Wood whites are one of our most delicate and slow-flying butterflies

Week-long lives

Butterflies emerging late from their chrysalises is not necessarily a problem for the insects, but the weather over the next few weeks may be crucial to their success.

Wet weather prevents butterflies from flying, which they need to do to find mates and plants on which to lay their eggs, explained Butterfly Conservation surveys manager Richard Fox.

"If those [weather] conditions carry on for the duration of your life as a butterfly - which might only be a week at best - then you leave no offspring."

And this year, butterflies appear to be in "very low numbers" following last year's poor weather.

"They really need some fine spring weather and a successful breeding season in order to start rebuilding their populations," said Mr Fox.

Grizzled skippers made a particularly late appearance this spring

He added that generally the UK's butterflies have suffered decades of decline, largely due to human destruction of their natural habitats.

"Nowadays these butterflies are so endangered... that a few years of bad weather might well drive colonies to extinction. And that's obviously exactly what we want to try and avoid."

Butterfly Conservation revealed its findings, gathered from public sightings of butterflies around the UK, ahead of Save Our Butterflies week which aims to introduce people to rare and threatened spring butterflies through a series of events and butterfly walks.

Mr Fox commented: "People tend to think of butterflies as at the height of summer and indeed that is when you tend to see most butterflies in your garden.

"But actually we have quite a lot of species, including some of our rare and threatened ones, which only come out at this time of year."

Invasive ladybirds wage 'biological war' on natives

By Matt McGrath Environment correspondent, BBC News

The Asian Ladybird or harlequin has overpowered native species across Europe

German researchers have discovered the biological keys to the success of an invasive species, wreaking havoc across Europe and the US,

The Asian ladybird was originally brought in to control aphids in greenhouses.

But it has escaped and is increasing uncontrollably across Europe, wiping out native species.

The alien is winning, say scientists, because its body fluid contains a parasite toxic to other insects.

The research is published in the Journal, Science.

“Start Quote

I don't see any which way to stop them now - it's too late in my opinion”

End Quote Dr Heiko Vogel Max Planck Institute

Sometimes called the harlequin, the Asian ladybird (Harmonia axyridis) can devour over two hundred aphids a day.

They are seen as a natural and effective solution to the problems posed by these pests in greenhouses.

Killer bugs

But in recent years these imported ladybirds have escaped and rapidly established themselves across Europe and North America at the expense of native species.

In Autumn, the Asian invaders can be a nuisance as they congregate in large groups searching for sheltered locations to hibernate.

They can sometimes cause serious allergic reactions in humans.

The larvae of the Asian ladybird can poison any native who eats it

In this new research, scientists have shown that it is the biological system of the Asian ladybird that gives it the edge when it comes to competing with native species.

The invader has an extremely powerful immune system.

The body fluid of the insect contains a strong antibiotic compound called harmonine as well as antimicrobial peptides. These allow the invasive to fight off pathogens more effectively than natives.

So powerful are the antibiotic elements in the ladybird, that the researchers say they may prove to be promising targets for drug development.

But the most powerful aspects of the ladybird's biological armoury are tiny fungi called microsporidia.

"They keep them inactive in their own blood, we don't understand how they do it yet," said Dr Heiko Vogel from the Max Planck Institute for Chemical Ecology,

"But when the other ladybird beetles start to attack the invader's eggs and larvae, they become active and kill the native ones."

The ladybird's immune systems have strong antimicrobial properties

Several studies in recent years have shown the harlequin conquering other ladybirds across Europe. In the UK scientists found that seven of the eight native British species have declined. Similar problems have been encountered in Belgium and Switzerland.

In the UK, researchers are very keen for people to report any sightings of the harlequin. They have just launched a smartphone app that helps people record details of the ladybirds.

Dr Helen Roy from the Centre for Ecology & Hydrology near Wallingford, UK, said the German research was "fascinating". The outlook for native species, however, remained grim.

"The two-spot ladybird, a historically common and widespread species in Britain is suffering the most and experiencing dramatic and rapid declines," she said.

And the German scientists agree that the Asian ladybird is set to conquer most of the world.

"I don't see any which way to stop them now - it's too late in my opinion," said Dr Vogel.

"The fascinating thing is they can survive in such a wide range of temperature zones, and they are starting to pop up in South Africa and South America."

When the aphids they prey upon become scarce, Asian ladybirds are known to feed on grapes and are often found in vineyards. Their powerful, defensive chemicals can affect the taste of wine if they get trapped in the production process.

"They go on apples and grapes and that is becoming an increasing problem because of the massive amounts of these beetles, said Dr Vogel.

"The tainting of the wine with a single beetle is not funny!"

ABOUT A CLOUDED LEOPARD

Clouded leopards are two species of wild cat that live throughout the forests of Southeast Asia. The smallest of the big cats, they are secretive and rare in the wild, preferring to remain alone and hidden from view. Because of this, studying them is a unique challenge, and while we know much from watching cats in captivity, these two species of cat remain elusive and poorly understood.

While all species of cats are closely related and classified as one family, the Felidae, genetic research has shown the clouded leopard to be more closely related to the large cat species than smaller cats. Thus, clouded leopards are considered a member of the Pantherinae - a subfamily of the Felidae family that also includes lions, tigers, jaguars, leopards, and snow leopards. While they are known as clouded leopards, cloudies are not directly related to normal leopards.

Until 2006, there was thought to be a single clouded leopard species. However, recent genetic and morphological research has shown that there are two distinct species. The cats on mainland Asia and Taiwan kept the traditional species name (Neofelis nebulosa) while the cats from Borneo and Sumatra took the name the Sunda clouded leopard (Neofelis diardi). Furthermore, this also changed the number of subspecies. All nebulosa subspecies have been combined into one group, while the diardi populations seem to be split into two subspecies: N. diardi borneensis on the island of Borneo and N. diardi diardi on Sumatra.

Photo: Alain Compost/WWF-Canon

The two species diverged from each other 1.5 million years ago due to geographic isolation as land bridges disappeared between the islands, possibly due to rising sea levels or volcanic eruptions¹. Ever since then the two species have not met nor interbre. In fact, even though they may look similar, genetically a clouded leopard is more different to its sister species than a lion is to a tiger!^2,3

With regards to appearance, the Sunda clouded leopard have smaller and darker cloud markings and a darker overall coat color. The majority of clouded leopard pictures are from mainland nebulosa individuals, meaning that photos of the Sunda clouded leopard are much more rare. Wild Sunda clouded leopards were only first caught on video in early 2010.

Clouded leopards primarily live in lowland tropical rainforests, but can also be found in dry woodlands and secondary forests. They have been spotted at elevations up to 9000 feet in the Himalayan mountains. Historically, their range covered most of Southeast Asia from Nepal and southern China through Thailand, Indonesia, and Borneo. However, this range has shrunk due to habitat destruction and human poaching.

map

Clouded leopards are a medium-sized cat named for the cloud-like spots on its coat. These provide camouflage in the dappled light of its forest habitat. (In China the cat is known as the 'Mint Leopard' because its spots can also look like mint leaves). The cats usually stand 10-16 inches (25-40cm) tall and are 4 to 6 feet (1.2-1.8m) long, almost half of which is the tail. Males tend to be larger and weigh up to 50 pounds (23 kg), while females rank in at about 35 pounds (16 kg). Clouded leopards can live to about 17 years old in captivity.

Fitting for an arboreal creature, clouded leopards are one of the best climbers in the cat family. They are able to climb upside down underneath tree branches, hang from branches with their hind feet, and even descend head first, like a squirrel. Several adaptations allow clouded leopards to achieve these amazing arboreal skills. Their legs are short and stout, providing leverage and a low center of gravity. Furthermore, a clouded leopard's extremely long tail provides an excellent balancing aid. For grip their large paws are armed with sharp claws and specialized padding that conforms to the shape of the branch⁴. The hind feet possess flexible ankle joints that allow the foot to rotate backwards as well.

Skull

Another distinctive feature of the clouded leopard is its long canine teeth and unusual skull. The clouded leopard has the longest upper canine teeth for its skull size of any modern carnivore, causing some people to compare the cat with the extinct saber-toothed cat. In fact, studies by Dr. Per Christiansen of the Copenhagen's Zoological Museum have revealed connections between the two groups. Dr. Christiansen's research into the skull characteristics of both living and extinct cats has revealed that that the structure of the clouded leopard skull bears distinctive resemblance to primitive saber-toothed cats such as Paramachairodus (before the group became highly specialized and developed enormous upper fangs ). Both saber toothed cats and clouded leopards have an enormous gape, around 100 degrees, and various adaptations to support such a gape. In contrast a modern lion can open its mouth about 65 degrees. This could indicate that one lineage of modern cats, of which now only the clouded leopard is still present, evolved some adaptations in common with the true saber-toothed cats.

It also indicates that the clouded leopard may hunt large prey in the wild in a slightly different manner from other great cats. Saber-toothed cats would bite prey through the neck, using their elongated teeth to sever nerves and blood vessels and strangle the windpipe, which would instantly kill the prey. This was a very different hunting technique from living big cats, which use a throat or muzzle grip to suffocate the prey. It is possible that clouded leopards use a similar technique. However, little is known about clouded leopard hunting strategies and no current evidence points to an unusual feeding ecology⁵.

Like all wild cats, clouded leopards are carnivores. They are thought to hunt a variety of prey including birds, squirrels, monkeys, deer, and wild pigs. It was once thought that clouded leopards hunted while climbing. Current thought, however, is that while some hunting may occur in the trees, most takes place on the ground. Trees are thought to provide resting habitat for cloudeds during the day.

Virtually nothing is known of the social behavior of wild clouded leopards. They are likely solitary, like most cats, unless associated with a mate while breeding or accompanied by cubs. Likewise, activity patterns are virtually unknown. Once thought to be exclusively nocturnal, evidence suggests that cloudeds may show some periods of activity during the day as well. It is known that they will patrol their territory (like all cats) and may use logging roads for hunting and travelling⁶. Territories range from about 20-50 km^{2, 7}.

babies

Clouded leopards are sexually mature around the age of 2 years. Mating can occur in any month, but in captivity most breeding occurs between December and March. The gestation period is 85 to 93 days long with 1 to 5 cubs per litter, although 2 is the most common number. Females can produce a litter every year. Cubs become independent at approximately 10 months of age.

In captivity, clouded leopards present a reproductive challenge. Unfortunately, there is a high incidence of aggression between males and females, sometimes resulting in the death of the female. This has made clouded leopards one of the most difficult cats to breed in captivity. Present captive management practices include introducing the members of a pair prior to one year of age. This practice has resulted in the establishment of more successful pair-bonds and lessening of aggression.

Like many animals in captivity, cubs are often hand-raised by keepers, rather than the mother. This depends on the temperament of the mother, the institution's facilities for newborns, and the health of the babies. More detailed information can be read in the Clouded Leopard Babies section.

NEWS ABOUT PUMA

Cougars make a comeback after a century of decline

By Matt McGrath Science reporter, BBC World Service

Cougars are moving east from their traditional western habitats

The American mountain lion or cougar is now re-populating parts of the US, scientists say.

Their numbers had plummeted in the last 100 years because of hunting and a lack of prey.

Writing in the Journal of Wildlife Management, researchers say the cougar is now spreading far outside their traditional western habitats.

But they say the return of the big cats raises important questions about how humans can live with these predators.

The cougars' decline was caused by hunting and a decline in their prey

Such has been the decline of the cougar in some parts of the United State that the US Fish and Wildlife service declared the eastern cougar extinct just last year.

For decades mountain lions were seen as a threat to livestock and humans and many States paid a bounty to hunters for killing them.

Their habitats were restricted to the areas around the Black Hills of Dakota. But in the 1960s and 70s the animals were reclassified as managed game species, so hunting was limited and numbers started to grow.

“Start Quote

They are very fleeting animals they're solitary and they don't like people”

End Quote Michelle LaRue University of Minnesota

Anecdotal evidence indicates that mountain lions started to spread far and wide during the 1990s - this perspective was confirmed last June when a young male was hit by a car and killed in Connecticut.

Genetic analysis indicated that the animal originated from the Black Hills and had travelled approximately 2,900km (1,800mi) via a number of States.

Now researchers have published the first scientific evidence that cougars have returned to the mid-west and are now to be found as far south as Texas and as far north as the Canadian provinces of Ontario and Manitoba.

They say that limits on hunting and the return of elk and mule deer that cougars prey on have been key to increasing the overall population which is now said to number around 30,000.

And as the populations have grown, the territorial instincts of the big cats have forced them to conquer new ground. Michelle LaRue from the University of Minnesota, is one of the authors of the paper.

"What's happening is that, as the young males are moving out of the areas they were born in, they are coming into contact with other young males and they don't have anywhere else to go so they're kind of being forced out of these western populations and into these areas of vacant habitats in the mid west," she said.

The team used recorded sightings that had been verified by wildlife professionals as well as carcasses, DNA evidence and cases of attacks on livestock across 14 State and provinces. And the scientists believe the spread of the cougar might continue.

"I would assume that with the continued management practices that have allowed for the rebound, cougars have the potential to continue to move eastward into areas of available habitat," said Michelle LaRue.

Many researchers are concerned that the spread of the mountain lion will inevitably bring them into conflict with humans. Other species such as bears have run into trouble thanks to their taste for human food. Ms LaRue said that cougars are very different.

"They are very fleeting animals they're solitary and they don't like people, they like to be in remote rugged wilderness areas, I say it's a lot less likely than they'll become dependent on trash like bears."

"If you were in the woods with a cougar and it saw it you wouldn't even know it, it would run before you even knew it was there."

THE REAL ME

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Indian tigers facing extinction, because of DNA

Loss of habitat

What future do Scotland's white-tailed eagles face?

Hunter in the wild

Tip to talon

The otter: return of the elusive movie star

Elusive otters

Places to see otters

Why hedgehogs are not welcome in the Hebrides

Hedgehog heaven

Worthy waders

'Big cat' Canadian lynx was on the loose in UK in 1903

Stink bugs: the scientific battle against an insect invasion

In today's Magazine

Bug eat bug world

Why do 'single' birds dance?

The wildlife school of dance

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Crane comeback

UK's rare spring butterflies make a late show

Butterfly bounty

Invasive ladybirds wage 'biological war' on natives

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Cougars make a comeback after a century of decline

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Pages

ANIMALS PAGE

Indian tigers facing extinction, because of DNA

Officials in Germany say Justin Bieber owes them thousands of pounds for his monkey's two month stay at a Munich animal shelter.

Loss of habitat

What future do Scotland's white-tailed eagles face?

Related Stories

Hunter in the wild

Tip to talon

The otter: return of the elusive movie star

Elusive otters

Places to see otters

Why hedgehogs are not welcome in the Hebrides

Related Stories

Hedgehog heaven

Worthy waders

'Big cat' Canadian lynx was on the loose in UK in 1903

Related Stories

Stink bugs: the scientific battle against an insect invasion

In today's Magazine

Bug eat bug world

Why do 'single' birds dance?

Related Stories

The wildlife school of dance

“Start Quote

Crane comeback

UK's rare spring butterflies make a late show

Related Stories

Butterfly bounty

Invasive ladybirds wage 'biological war' on natives

Related Stories

“Start Quote

ABOUT A CLOUDED LEOPARD

Cougars make a comeback after a century of decline

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