0:00:17 > 0:00:21Welcome to Reporters, I'm Philippa Thomas.
0:00:21 > 0:00:25From here in the world's newsroom we send out correspondents to bring
0:00:25 > 0:00:27you the best stories from across the globe.
0:00:27 > 0:00:29In this week's programme...
0:00:29 > 0:00:33The Philippines' deadly war on drugs.
0:00:33 > 0:00:37Jonathan Head joins a police prison raid and finds drug addicts
0:00:37 > 0:00:39and dealers filling the cells to escape the death squads.
0:00:39 > 0:00:42The focus at the moment, as with so much of this campaign,
0:00:42 > 0:00:45is people at the very bottom of the trade,
0:00:45 > 0:00:48not the people running it.
0:00:48 > 0:00:51On the front line in Libya's war against the so-called Islamic State.
0:00:51 > 0:00:54Feras Kilani joins pro-government forces besieging the strategic city
0:00:54 > 0:00:59of Sirte, seized by IS a year ago.
0:00:59 > 0:01:02The anti-government forces have mobilised all their ability, really.
0:01:02 > 0:01:06To retake the last two districts still under Isis control.
0:01:06 > 0:01:09Closer to extinction.
0:01:09 > 0:01:12As Africa's elephant population falls, Alistair Leithead joins
0:01:12 > 0:01:16the mammoth operation to carry out the first ever aerial census
0:01:16 > 0:01:23and finds the poachers are still a big problem.
0:01:23 > 0:01:28We have been flying along this flood plain that divides Namibia
0:01:28 > 0:01:31and Botswana and all the way along here we have been seeing
0:01:31 > 0:01:37carcasses of elephants.
0:01:37 > 0:01:38I am a Romany Gypsy.
0:01:38 > 0:01:40I am fiercely proud of my identity.
0:01:40 > 0:01:41Jeremy Cooke meets Britain's Romany Gypsies fighting
0:01:41 > 0:01:46to save their traditional way of life.
0:01:46 > 0:01:49And the secret life of birds.
0:01:49 > 0:01:52Victoria Gill gets exclusive access to the scientists shedding new light
0:01:52 > 0:01:57on the mysteries of flight.
0:01:57 > 0:02:00Wind tunnels have been used for a long time to study bird flight
0:02:00 > 0:02:03but the new thing about this one is that with this device, they can
0:02:03 > 0:02:07manipulate the airflow to recreate any environment on Earth.
0:02:07 > 0:02:11There has been an unprecedented rise in the murder rate in
0:02:11 > 0:02:21the Philippines after the country's new president won power promising
0:02:21 > 0:02:24tough action in the war on drugs.
0:02:24 > 0:02:26But Rodrigo Duterte's critics say his hard-line tactics
0:02:26 > 0:02:29include turning a blind eye to extrajudicial killings.
0:02:29 > 0:02:31One campaign promise included a pledge to kill 100,000 criminals
0:02:31 > 0:02:34in his first six months in office, while nearly 2000 people have
0:02:34 > 0:02:37died in the seven weeks since the crackdown began.
0:02:37 > 0:02:40Police say hundreds of thousands of dealers and drug users have
0:02:40 > 0:02:48turned themselves in.
0:02:48 > 0:02:50Jonathan Head joined the police as they raided one
0:02:50 > 0:02:54of the biggest prisons in Manila.
0:02:54 > 0:02:57The war on drugs is reaching all corners of the Philippines.
0:02:57 > 0:03:02Even here, in the jails.
0:03:02 > 0:03:06Many of these men are already serving long sentences for drug use
0:03:06 > 0:03:09in cells so packed with bodies it is hard to breathe.
0:03:09 > 0:03:13It says something about the extent of the drug problem here
0:03:13 > 0:03:18in the Philippines that the police have had to come here and raid one
0:03:18 > 0:03:20of the biggest prisons around Manila.
0:03:20 > 0:03:23There are clearly concerns about real drug problems
0:03:23 > 0:03:27here but the focus at the moment, as with so much of this campaign,
0:03:27 > 0:03:29is people at the very bottom of the trade,
0:03:29 > 0:03:36not the people running it.
0:03:36 > 0:03:38At least here they can stay alive.
0:03:38 > 0:03:40But not here.
0:03:40 > 0:03:45The bodies of dealers and addicts are discovered every night
0:03:45 > 0:03:49in the slums of Manila, killed either by the police
0:03:49 > 0:03:52or by shadowy hit squads.
0:03:52 > 0:03:55It started when this man, Rodrigo Duterte, an outspoken
0:03:55 > 0:03:57crime-fighting Mayor, was elected president in May.
0:03:57 > 0:04:06When he said he would kill drug dealers, he meant it.
0:04:06 > 0:04:09Does the lives of ten criminals really matter to me?
0:04:09 > 0:04:17If I am the one facing the grief, would 100 lives mean anything to me?
0:04:17 > 0:04:21The president is still wildly popular for this kind of talk.
0:04:21 > 0:04:24Drug addiction has blighted neighbourhoods already
0:04:24 > 0:04:28burdened by poverty.
0:04:28 > 0:04:31But his campaign has forced Roger - not his real name - into hiding.
0:04:31 > 0:04:34He has been a minor drug dealer for years.
0:04:34 > 0:04:44Now he is on the run.
0:04:46 > 0:04:49TRANSLATION: I have done some awful things, I know.
0:04:49 > 0:04:52I have wronged a lot of people because they have
0:04:53 > 0:04:56become addicted to drugs.
0:04:56 > 0:04:59Because I am one of the many who sells the drugs.
0:04:59 > 0:05:00Not everyone who uses drugs commits crimes.
0:05:00 > 0:05:02Me? I am an addict but I don't kill.
0:05:02 > 0:05:04This chilling security camera video shows why those targeted
0:05:04 > 0:05:09by the anti-drug campaign have so much to fear.
0:05:09 > 0:05:12A motorbike slows down for a moment.
0:05:12 > 0:05:16The passenger firing at point-blank range.
0:05:16 > 0:05:20It might easily have been Maria, a young mother and a hired assassin.
0:05:20 > 0:05:22She says she has killed five people since President Duterte
0:05:22 > 0:05:25won the election.
0:05:25 > 0:05:31Like Roger, she says it was poverty that drove her into the job.
0:05:31 > 0:05:33TRANSLATION: I tell my husband that we cannot keep
0:05:33 > 0:05:35doing this forever.
0:05:35 > 0:05:37We have children.
0:05:37 > 0:05:40We don't want our children to know what we do.
0:05:40 > 0:05:44I do not want them to come back at us and say that they got to live
0:05:44 > 0:05:46because we killed for money.
0:05:46 > 0:05:49Nearly 700,000 terrified drug addicts have already surrendered
0:05:49 > 0:05:52to the Philippines police to save their lives.
0:05:52 > 0:05:56They must somehow now be accommodated in these
0:05:56 > 0:06:05teeming, overcrowded cells.
0:06:05 > 0:06:08It is a strategic Libyan city on the Mediterranean coast.
0:06:08 > 0:06:12Seen as a gateway from North Africa to Europe.
0:06:12 > 0:06:15Sirte was seized by so-called Islamic State forces last year
0:06:15 > 0:06:18and there were fears that IS would use the port as a base
0:06:18 > 0:06:21to attack European targets.
0:06:21 > 0:06:24But this week, pro-government forces said they had retaken most
0:06:24 > 0:06:29of the city and were flushing out the last of the fighters.
0:06:29 > 0:06:32Militia groups aligned to the so-called Libyan Government
0:06:32 > 0:06:37of National Accord have been supported by US air strikes.
0:06:37 > 0:06:40Feras Kilani and cameraman Jamie Bowles are among the few
0:06:40 > 0:06:43international teams to have reached the front line and they
0:06:43 > 0:06:48sent us this report.
0:06:48 > 0:06:52The tanks begin to advance.
0:06:52 > 0:06:54The militants of so-called Islamic State are cornered.
0:06:54 > 0:07:03Forces loyal to the unity government are now pounding their positions.
0:07:03 > 0:07:07And close to regaining control of Sirte.
0:07:07 > 0:07:09The anti-government forces have mobilised all of their ability
0:07:09 > 0:07:15to retake the last two districts still under Isis control.
0:07:15 > 0:07:20Islamic State hoped their headquarters in Sirte would provide
0:07:20 > 0:07:26a base to launch attacks into Europe.
0:07:26 > 0:07:34But now the extremists are about to be pushed out.
0:07:34 > 0:07:37The commander here tells me that IS no longer have the manpower
0:07:37 > 0:07:41to hold the city.
0:07:41 > 0:07:46TRANSLATION: All the area in front of us is under IS control.
0:07:46 > 0:07:51You can see them from here.
0:07:51 > 0:07:53It is districts number one and three.
0:07:53 > 0:07:58Within a few days we will take over all this area, by the help of God.
0:07:58 > 0:08:03But the fight isn't over yet.
0:08:03 > 0:08:06IS militants quickly reply with sniper fire and suicide bombs.
0:08:06 > 0:08:10Stopping the advance.
0:08:10 > 0:08:13The military spokesman told us that they had
0:08:13 > 0:08:17expected these attacks.
0:08:17 > 0:08:21And he is confident with his men's progress.
0:08:21 > 0:08:24TRANSLATION: We are now in control of 75% of district three
0:08:24 > 0:08:27and IS fighters have retreated towards the coast.
0:08:27 > 0:08:30The fighting in district one is still intense but we will not
0:08:30 > 0:08:37struggle to get the job done.
0:08:37 > 0:08:41But the gains here have come at a price.
0:08:41 > 0:08:45On the day we visited this hospital, over 30 fighters were killed.
0:08:45 > 0:08:50And we watch as medical staff battle to treat almost 200 men.
0:08:50 > 0:08:56Even if IS are forced out of Sirte, their threat continues.
0:08:56 > 0:09:00There is a strong feeling that IS will regroup and return,
0:09:00 > 0:09:05causing more devastation in a struggling country with two
0:09:05 > 0:09:13governments and hundreds of militias competing for power.
0:09:13 > 0:09:16The number of elephants living in the wild in Africa
0:09:16 > 0:09:20has fallen drastically over the past decade.
0:09:20 > 0:09:22Ivory poachers are mainly responsible.
0:09:22 > 0:09:26A new Africa-wide survey that extends from Mali to Ethiopia
0:09:26 > 0:09:29and South Africa suggests numbers have fallen by a third
0:09:30 > 0:09:34in the past decade.
0:09:34 > 0:09:37Botswana is home to more than 40% of the continent's elephants,
0:09:37 > 0:09:41but as Alastair Leithead reports, poachers are now active there.
0:09:41 > 0:09:46Some viewers might find some of these images distressing.
0:09:46 > 0:09:50What other way to count a whole continent of elephants
0:09:50 > 0:09:55but from the air?
0:09:55 > 0:09:58For two years they have been flying just 300 feet above Africa's
0:09:59 > 0:10:01savanna grasslands.
0:10:01 > 0:10:04It takes a keen eye or a camera to count each
0:10:04 > 0:10:06of the animals below.
0:10:06 > 0:10:09And, sadly, their findings paint a depressing picture.
0:10:09 > 0:10:11What's that?
0:10:11 > 0:10:13Is that another one?
0:10:13 > 0:10:18In country after country, they have counted the carcasses.
0:10:18 > 0:10:21This one is fresh.
0:10:21 > 0:10:24This is the cost of the poachers and traffickers serving Asia's
0:10:24 > 0:10:27insatiable appetite for ivory.
0:10:27 > 0:10:31We have been flying along this flood plain that divides Namibia
0:10:31 > 0:10:34and Botswana and all the way along here we have been seeing
0:10:34 > 0:10:35carcasses of elephants.
0:10:35 > 0:10:37Some four months old, some less than a week old.
0:10:37 > 0:10:40And there is one just down here.
0:10:40 > 0:10:43Clearly poaching.
0:10:43 > 0:10:45The face has been hacked away to get to the tasks.
0:10:45 > 0:10:48Mike Chase led the census research.
0:10:48 > 0:10:51He found the worst hotspots of poaching are in Tanzania,
0:10:51 > 0:10:54Mozambique and Angola.
0:10:54 > 0:10:59Each year we are losing nearly 30,000 elephants and if this current
0:10:59 > 0:11:02rate continues, within nine years Africa could be left with half
0:11:02 > 0:11:07of the current estimate of African elephants.
0:11:07 > 0:11:10Botswana has 40% of Africa's elephants, but amid the worst
0:11:10 > 0:11:14drought in decades, they are under increasing pressure.
0:11:14 > 0:11:17The only way to protect them is to know how many
0:11:17 > 0:11:19there are and where they go.
0:11:19 > 0:11:27And that means tranquillising some to fit satellite tracking collars.
0:11:27 > 0:11:31It takes just a few minutes for the drugs to take effect.
0:11:31 > 0:11:37You have to be careful the trunk is not blocked.
0:11:37 > 0:11:43This elephant is about 50 years old, given his size.
0:11:43 > 0:11:47And the fact that the collar has to be really big to get that GPS
0:11:47 > 0:11:51tracker around his neck.
0:11:51 > 0:11:55They are trying to work as quickly as they can so they can get him
0:11:55 > 0:11:56round as soon as possible.
0:11:56 > 0:11:59But he will be fine.
0:11:59 > 0:12:02The quicker the whole process is done, the better.
0:12:02 > 0:12:06Then, inject the antidote and retreat to a safe distance.
0:12:06 > 0:12:08OK, get out of here.
0:12:08 > 0:12:11There is one foot that has been underneath him.
0:12:11 > 0:12:13You can do it.
0:12:13 > 0:12:17Go on, you can do it.
0:12:17 > 0:12:19This map illustrates the movements of five
0:12:19 > 0:12:23satellite collared elephants.
0:12:23 > 0:12:26The tracking data shows how elephants, the dots, used to travel
0:12:26 > 0:12:28across five countries.
0:12:28 > 0:12:31But now they stop at the border.
0:12:31 > 0:12:32They know it is too dangerous.
0:12:32 > 0:12:35Elephants clearly have a cognitive ability to understand
0:12:35 > 0:12:38where they are threatened and where they are safe and in this
0:12:38 > 0:12:40case they are seeking refuge and sanctuary in Botswana.
0:12:40 > 0:12:41Where they are well protected.
0:12:41 > 0:12:43And is there room for them?
0:12:43 > 0:12:46SIGHS.
0:12:46 > 0:12:49No.
0:12:49 > 0:12:51Even without a drought, Botswana cannot cope
0:12:51 > 0:12:54with so many elephants.
0:12:54 > 0:12:58Hunting has been banned here, culling is even being discussed.
0:12:58 > 0:13:02Currently we're housing a lot of refugee elephants in Botswana.
0:13:02 > 0:13:07The biomass of elephants in Botswana is so high per square kilometre
0:13:07 > 0:13:13that it puts a lot of pressure on the environment.
0:13:13 > 0:13:18And the last true sanctuary for Africa's elephants is,
0:13:18 > 0:13:24for the first time, now firmly in the poachers' sights.
0:13:24 > 0:13:34There were days on the great elephants census when I thought
0:13:37 > 0:13:41the only good I was doing was recording the disappearance
0:13:41 > 0:13:46of one of the most remarkable animals that walk this planet.
0:13:46 > 0:13:49But we have to be hopeful.
0:13:49 > 0:13:50At least, yeah...
0:13:50 > 0:13:53The campaign to stop the poachers and the traffickers
0:13:53 > 0:13:54across the continent continues.
0:13:54 > 0:13:57Now, a traditional way of British life with hundreds of years
0:13:57 > 0:13:59of history behind it could be under threat.
0:13:59 > 0:14:01Romany Gypsies say government policy is threatening
0:14:01 > 0:14:04to destroy their livelihoods.
0:14:04 > 0:14:08Changes to planning rules in England introduced a year ago mean those
0:14:08 > 0:14:11who stop travelling are unlikely to be granted permission
0:14:11 > 0:14:14for a new site.
0:14:14 > 0:14:16The government says it wants a fair system which gives
0:14:17 > 0:14:24councils more power.
0:14:24 > 0:14:26But as Jeremy Cooke reports, gypsies believe they
0:14:26 > 0:14:27are victims of racism.
0:14:27 > 0:14:29This place is literally sacred to us.
0:14:29 > 0:14:39This gives us a sense of place.
0:14:39 > 0:14:42A sense of belonging.
0:14:42 > 0:14:46A sense of ancestry.
0:14:46 > 0:14:50Appleby Fair.
0:14:50 > 0:14:53A celebration of a way of life.
0:14:53 > 0:14:55I am a Romany Gypsy.
0:14:55 > 0:14:56I am fiercely proud of my identity.
0:14:56 > 0:14:58My culture.
0:14:58 > 0:14:59My language and my traditions.
0:14:59 > 0:15:00And my history.
0:15:00 > 0:15:01The gypsy community.
0:15:01 > 0:15:04Immersed in a culture which has endured for hundreds of years.
0:15:04 > 0:15:07Washing the horses in the river, we have been doing that ever
0:15:07 > 0:15:09since we arrived in this country 500 years ago.
0:15:09 > 0:15:12We have been coming to this fair and ever since we have been washing
0:15:12 > 0:15:15the horses in the river in the exact same way.
0:15:15 > 0:15:17Today they are enjoying their day in the sun.
0:15:17 > 0:15:18But gypsy life is not easy.
0:15:18 > 0:15:23Many families have now abandoned their traditional life on the road.
0:15:23 > 0:15:28There is a desperate shortage of caravan sites.
0:15:28 > 0:15:38That is why 80% of our people are in houses.
0:15:42 > 0:15:45Because they got so desperate, it got so difficult for them.
0:15:45 > 0:15:46They have been forced into houses.
0:15:46 > 0:15:50And they don't want to be in houses, they want to be on a caravan site.
0:15:50 > 0:15:52The pressures of modern life mean gypsies often reluctantly move
0:15:52 > 0:15:55into houses for work, for school or because of age
0:15:55 > 0:15:56or health problems.
0:15:56 > 0:15:59But the law changes in England mean that once they come off the road,
0:15:59 > 0:16:02even for a short time, they can now find it impossible
0:16:02 > 0:16:03to return to caravan life.
0:16:03 > 0:16:06Trying to get planning permission for a caravan site as a Gypsy
0:16:06 > 0:16:08traveller has become more and more difficult.
0:16:08 > 0:16:10It is all down, I have to say, to prejudice.
0:16:10 > 0:16:12Prejudice on the part of the general population against
0:16:12 > 0:16:13gypsies and travellers.
0:16:13 > 0:16:16It is harder and harder and harder for people to find somewhere.
0:16:16 > 0:16:19It took Nichola 12 years to win a planning battle in North
0:16:19 > 0:16:20Yorkshire.
0:16:20 > 0:16:22I have got seven children so it is hard.
0:16:22 > 0:16:25We're just trying to settle down and give them the best
0:16:25 > 0:16:26in life you can.
0:16:26 > 0:16:27And do the best for them.
0:16:27 > 0:16:30And so when they get older, they can do that for their family.
0:16:30 > 0:16:33Everybody else is up there, the travellers are down there.
0:16:33 > 0:16:35And it has been like that for a long time.
0:16:35 > 0:16:38No matter how much you shout, people just don't want to know.
0:16:38 > 0:16:41Away from the romance of the summer fair, what gypsies want is this.
0:16:41 > 0:16:43Purpose-built sites.
0:16:43 > 0:16:45This one is in Darlington.
0:16:45 > 0:16:49We have got the caravans that we use for bedrooms and living rooms.
0:16:49 > 0:16:51We have a smaller caravan for the children.
0:16:51 > 0:16:53We have all the conveniences that people have in a house,
0:16:53 > 0:16:56but at the same time, we're hanging on to our culture
0:16:56 > 0:16:57and our traditions.
0:16:57 > 0:16:59These new rules only apply in England.
0:16:59 > 0:17:02Ministers say councils now have more power to stop unauthorised camps
0:17:02 > 0:17:06and more freedom to decide what sites to provide.
0:17:06 > 0:17:10The government insists it treats all communities equally.
0:17:10 > 0:17:13But some believe that gypsies, far from being victimised,
0:17:13 > 0:17:17are being given unfair advantages.
0:17:17 > 0:17:23I think travellers who travel probably do have a strong case.
0:17:23 > 0:17:26But travellers who don't travel, who are seeking a permanent
0:17:26 > 0:17:28lifestyle on a particular spot in the countryside,
0:17:28 > 0:17:33shouldn't have the right to build where no one else can.
0:17:33 > 0:17:35It all leaves gypsies fearing they are being forced
0:17:35 > 0:17:39still further to the margins.
0:17:39 > 0:17:42There is generally people in this world today who think
0:17:42 > 0:17:45it is a crime just to be a gypsy.
0:17:45 > 0:17:48And they generally think we shouldn't be allowed to exist.
0:17:48 > 0:17:52We shouldn't have any rights.
0:17:52 > 0:17:55And so, England's gypsies fear an uncertain future.
0:17:55 > 0:18:00But the government insists it is up to local communities to decide
0:18:00 > 0:18:06what sites to provide for those who choose the travelling life.
0:18:06 > 0:18:10The Paralympics begin in Rio in a few days' time, with Britain
0:18:10 > 0:18:14hoping to repeat its success in the Olympics two weeks ago.
0:18:14 > 0:18:16It is sending a team of more than 260 athletes.
0:18:16 > 0:18:21Among them is Joe Townsend from Eastbourne, who will be
0:18:21 > 0:18:25competing in the Paratriathlon.
0:18:25 > 0:18:28He was injured while serving with the Royal Marines
0:18:29 > 0:18:32in Afghanistan.
0:18:32 > 0:18:36Our reporter, Kate Gray, herself a former Paralympian,
0:18:36 > 0:18:38has been to meet him.
0:18:38 > 0:18:48In February in 2008, when I stepped on the improvised explosive device,
0:18:51 > 0:18:53I didn't really know what I was doing with my life.
0:18:53 > 0:18:56I remember sitting there on the battlefield in Afghanistan,
0:18:56 > 0:18:59thinking, what am I going to do now?
0:18:59 > 0:19:01Six weeks in intensive care.
0:19:01 > 0:19:04Three years in rehabilitation and over 50 operations.
0:19:04 > 0:19:06The road to recovery hasn't been easy for Joe.
0:19:06 > 0:19:09Even daft things like carrying a cup of tea whilst being in a wheelchair
0:19:09 > 0:19:11is a completely different challenge.
0:19:11 > 0:19:14For me, it has been a steep learning curve and trying to find
0:19:14 > 0:19:16ways around doing just mundane, everyday tasks.
0:19:16 > 0:19:19I know a lot of guys really struggle and dwell on the past,
0:19:19 > 0:19:22on what has happened to them, and it is fully understandable
0:19:22 > 0:19:24if you have been young, fit and active and had something
0:19:24 > 0:19:27horrendous happen to you, then it is easy to look
0:19:27 > 0:19:29back and think, why me?
0:19:29 > 0:19:31Why has this happened to me?
0:19:31 > 0:19:34But I could just look forward in life and look to see
0:19:34 > 0:19:38what I could strive to achieve and move forwards, really.
0:19:38 > 0:19:41Once, when I was maybe six months into my rehabilitation
0:19:41 > 0:19:44at Headley Court, I started trying different adapted sports.
0:19:44 > 0:19:47You're kind of free and your discipline becomes irrelevant.
0:19:47 > 0:19:50I kind of got that competitive edge back and that spark.
0:19:50 > 0:19:52Actually, I like this and it gives me the opportunity
0:19:52 > 0:19:55to push myself again.
0:19:55 > 0:19:57Despite the fact that his sport, the triathlon, was not included
0:19:57 > 0:20:03in the London 2012 Paralympics, he still found a way to be involved.
0:20:03 > 0:20:06Joe Townsend!
0:20:06 > 0:20:10That day there, actually coming into the stadium with thousands
0:20:10 > 0:20:13of people cheering, that really set it in my head that I want to be
0:20:13 > 0:20:16there in Rio.
0:20:16 > 0:20:20Not for a theatrical piece, I want to be there with my sport.
0:20:20 > 0:20:23Joe has spent the last four years preparing for Rio.
0:20:23 > 0:20:27He believes he is now in the best shape of his life.
0:20:27 > 0:20:30Triathlon is one of my sports and anything can happen, really.
0:20:30 > 0:20:33If I can deliver my best race on the day and give 100%
0:20:33 > 0:20:36of what I know I have been doing in training, then yes.
0:20:36 > 0:20:40I definitely have the option of getting on the podium.
0:20:40 > 0:20:44I served my country as a Royal Marine in Afghanistan
0:20:44 > 0:20:48and being able to fly the GB flag again and represent my country
0:20:48 > 0:20:51as an athlete, it has gone from one life to another
0:20:51 > 0:20:54but it is a fantastic experience.
0:20:54 > 0:20:57I can't wait.
0:20:57 > 0:21:00Have you ever wondered how even the tiniest birds manage to fly
0:21:00 > 0:21:02in strong, gusty winds?
0:21:02 > 0:21:05Well, scientists at Stanford University in California have now
0:21:05 > 0:21:09designed a bird wind tunnel to try to find out.
0:21:09 > 0:21:12Victoria Gill has had exclusive access to the flight lab
0:21:12 > 0:21:15revealing new details about the secret life of birds.
0:21:15 > 0:21:21The wonder of flight.
0:21:21 > 0:21:26Only in very slow motion can we see the minuscule adjustments this
0:21:26 > 0:21:30lovebird constantly makes to its flapping wings.
0:21:30 > 0:21:33Its tiny body has evolved perfectly to fly.
0:21:33 > 0:21:37Human engineers haven't come close to recreating that.
0:21:37 > 0:21:39Here it is.
0:21:39 > 0:21:41It is pretty big.
0:21:41 > 0:21:43It's huge!
0:21:43 > 0:21:46That is something that researchers in this lab hope to change.
0:21:46 > 0:21:49They have dedicated an entire room at Stanford University in California
0:21:49 > 0:21:51to building this wind tunnel.
0:21:51 > 0:21:53The only one of its kind in the world.
0:21:53 > 0:21:55OK, so this is where you fly the birds?
0:21:55 > 0:21:58Yes.
0:21:58 > 0:22:01Basically, you can go in here...
0:22:01 > 0:22:06It is starting to help them discover some of the birds' crucial secrets.
0:22:06 > 0:22:09Wind tunnels have been used for a long time to study bird flight
0:22:09 > 0:22:12but the new thing about this one is that with this device they can
0:22:12 > 0:22:16manipulate the airflow to recreate any environment on Earth,
0:22:16 > 0:22:22from a gusty city to the top of a mountain.
0:22:22 > 0:22:25When you see a bird fly by in a city you see all of these
0:22:25 > 0:22:28small motions in the wing and that is all that it is doing
0:22:28 > 0:22:31to adjust to the turbulence.
0:22:31 > 0:22:34And so it is really these tiny motions where they adapt quickly
0:22:34 > 0:22:35that make the difference.
0:22:35 > 0:22:38And we have no idea how they make these in response to
0:22:38 > 0:22:42which wind flow patterns.
0:22:42 > 0:22:45In the moving air the bird remains in one place so exactly how it
0:22:45 > 0:22:52shifts as the airflow changes can be seen in unprecedented detail.
0:22:52 > 0:22:56But the team, with their specially clicker-trained birds,
0:22:56 > 0:22:59have also measured invisible characteristics of short hopping
0:22:59 > 0:23:03flights like this one.
0:23:03 > 0:23:07This setup is unique because it allows us to capture all the forces
0:23:07 > 0:23:10that a bird generates from the moment it takes off
0:23:10 > 0:23:14to when it lands during one of these fights.
0:23:14 > 0:23:17We have been able to record that actually, most birds when they fly,
0:23:17 > 0:23:20they generate twice as much lift during the downstroke to support
0:23:20 > 0:23:22the complete body weight and during the upstroke
0:23:22 > 0:23:24they are actually in freefall.
0:23:24 > 0:23:27So what can be done with all of this flight insight?
0:23:27 > 0:23:31The next generation of small-scale flying robots, or drones,
0:23:31 > 0:23:34will need to cope in unstable environments if they are to be
0:23:34 > 0:23:36useful in military or search and rescue applications.
0:23:36 > 0:23:38Currently they simply cannot manage as smoothly as birds.
0:23:38 > 0:23:42So these scientists will aim to create robotic copies
0:23:42 > 0:23:51of what nature has perfected over millions of years.
0:23:51 > 0:23:52Fascinating stuff.
0:23:52 > 0:23:55And that's all from Reporters for this week.
0:23:55 > 0:24:01From me, Philippa Thomas, goodbye for now.
0:24:01 > 0:24:05From me, Philippa Thomas, goodbye for now.