La vie secrète des pigeons (sous titres français)

La vie secrète des pigeons (sous titres français)

August 18, 2019 1 By William Hollis


this is the nature of things [Music] in the city we cross paths with them every day mostly we’re oblivious pigeons have receded into the background of our urban landscapes eating off the street and hanging out on the wires and ledges overhead when we do take notice most of us just see a messy pest and not a true marvel of the natural world today these big-city birds carry a low-rent reputation it’s a stunning downfall considering how smart they are and their heroic place in our history this is the story of pigeons as you’ve never seen them before [Music] [Applause] [Music] [Applause] [Music] [Applause] they’re tough guys urban survivors and there’s a story of the streets of rags to riches and back again but they’re also a marvel in the air and a testament to nature’s resilience stop look and admire the pigeon in Montreal neukölln Giraldo is a scientist with a mission he wants us to open our eyes and hearts to these remarkable creatures and regard them as he does with all when I was a kid we had a pigeon coop at home and we had to get rid of it the neighbors complained and I remember we didn’t have a car so my uncle came in put the pigeons in the trunk he had brought them out into the countryside by the time my uncle was back the pigeons had been in my backyard waiting for at least half an hour that was very impressive for a little guy like me few animals on earth have tougher lies than the pigeons that live on our streets most of them are never more than a few days from starvation job number one is finding something to eat I would say that only a minority of them actually get to to build a nest get a mate have a some young and most of them die in the nest anyways because it’s just cold it’s miserable there’s not enough food to feed them and so on and then you start again the next morning and if it snows and Sun suddenly becomes minus 20 then you need even more food so you have to plan ahead before you go to bed you got to make sure that you’ve you filled up as much as you could on food and if the person that would normally feed you didn’t come that evening you’re in deep trouble like domestic pets pigeons rely on us for food but bugs whose food ball gets refilled every day these birds have no such guarantee vigils must always be reading the cues from us about where and when they can expect a few scraps people love the idea of actually getting them to come into their hand we can do that especially if they’re very hungry they’re not afraid of humans so it allows us to create some kind of a rapport with them this relationship between bird and human is more complex than it might look pigeons have learned to have lookouts to spot and remember faces even from a distance they recognize people who feed them routinely long before they sit down and open a bag of breadcrumbs they can start to recognize people by the way they walk and their routine every day because people tend to have routines so they may come at lunchtime for example and they may feed the pigeons every lunchtime pigeons will wait for that individual they can see that person coming a mile away before they even pull anything out of their bag not only can pigeons recognize a friendly face they never forget a foe pigeons can actually attend to people’s facial features which is pretty weird for a little bird to be able to tell people apart in Toronto scientists Susanne McDonald is conducting an experiment to show how pigeons can distinguish Ally from enemy you had two people and they’re each wearing different colored coats and they sit down and one person is the good cop and one person is the bad cop both people feed the birds but one of them also shoes them away then you find that the birds go to the one that’s feeding them and not shooting them away well that’s not too exciting to test their memory retention the scientists leave the area altogether return later on and try feeding them again but the birds remember which was which and once more avoid the person who’d been their tormentor and you might say well they’re just learning other features like maybe the colors of the coat or some obvious difference between them in a third session the experiment calls for a disguise to really test their powers of recognition what you do is you have the experimenters then switch coats after swapping coats and positions both begin to feed them again amazingly despite the changes the pigeons only respond to Suzanne the one they regard it from the start as safe which means the only cues they could use would be their facial features which is pretty cool because it means that the pigeons are not only just walking by us in the park but they’re actually noticing us and remembering who’s good to them and who’s bad to them they are way smarter than you think they are [Applause] as one of nature’s beggars pigeons rely on street smarts to make the most of their measly prospects forming a kind of network they spread out dividing the city into territories where each bird gets the same amount of food it’s a concept scientists call ideal free distribution if you measure how many pigeons you find in a park in downtown Montreal it actually does correspond almost precisely to the relative proportion of food compared to the other parts that is present in this one part so imagine if one Park has twice as much food as this other part there are twice as many pigeons if if another Park has five times more food and as pie finds more pigeons the only way you can get a population like that is if they can actually work where they will spread out in a simple experiment Luke Allen and his research assistant Carolyn feed the birds a few feet apart but at different rates for every sprinkling of corn Carolyn puts down Luke Alan puts down double it doesn’t take long to see how the pigeons divide themselves up so that effectively they all end up with the same amount well what you’ll see is pigeons and reaching at an equilibrium in relation to the amount of food if we count the birds if you stop frame and you count the birds you’ll see it’s almost exactly double the number of birds on one then there are any others said it means that the pigeons over here are not getting any more food per per capita than the pigeons over there so if I’m giving out more food to these pigeons what I’m really doing is I’m bringing in more pigeons I’m not feeding them more what will happen is if I do this regularly it will suck in pigeons from elsewhere so the population will grow you can never feed pigeons more you can just attract more pitches [Music] and so this distribution is actually a very universal phenomenon it explains the distribution of fish in the ocean birds in the forest and it’s called the ideal free distribution this sense of common purpose begins in the nest females and males take turns incubating eggs [Music] during breeding season parents will nest under awnings behind storefronts anywhere they can away from the wind and hidden from predators and other threats although pigeons live in risky environments they’re very good at reproducing their global population is estimated at 400 million watching them together the birds show a tender side we don’t expect from such outcasts their affectionate caring and dedicated animals there are monogamous and they they form a long-term pair bond I wouldn’t say that they’re faithful but but certainly socially at least they form a pair of bonds the males are always open for an affair and so you can see that males are always cooing uh and they can’t tell males from females so they just do anything both parents feed their chicks pidgin milk a special secretion from a pouch inside their throats adults can eat almost anything they find and turn it into milk no need to search high and low for seeds or insects like most other birds they also only have 37 taste buds to our 10,000 making it all go down a little easier the young chick is covered with yellow down feathers on its first day of life because the milk is nutrient-rich the nestlings double their weight in just a day and a half [Music] it’s one reason why pigeons are one of the fastest growing vertebrates on earth rarely noted for their beauty these animals are born with a kind of punk look that suits their tough city lives on the seventh day the plumage forms two dark rows along its back and by the 14th the flight feathers begin to emerge after three weeks the squab is covered all over with feathers but the tail is still missing feathering is completed on the 28th day when body weight has reached its maximum [Music] once the young start being able to leave the nest they become the responsibility of the male the male will take them around because the female is busy playing another clutch and the male is responsible for taking the young around teaching them the the places where there’s food to make it out here on the mean streets of downtown pigeons evolved a whole range of skills that help them evade dangers at every turn it starts with exceptional eyesight they have a highly developed collapsing sense which means they can extrapolate the movement of objects including cars and humans and precisely predict when they might get hit humans our best vision is right in front of us but they can see on their periphery on the side as well as in the center and those two areas of their I actually go to different parts of their brain so their brain is set up to see and set up to use that information very quickly which is why I think they don’t get killed by cars that’s what I think they can evil avoid predators they are just kind of perfect little creatures roaming our city streets vigils see the world in slow motion if they were to watch a movie which is typically 24 frames per second it would move as slowly to them as a slide presentation closer to 75 frames per second because of that the car bearing down on them looks to be moving at a snail’s pace sometimes you go oh my gosh like pigeons gonna get run over pigeons never get run over you never see a dead pigeon by the side of the road because they get out of the way so they’re much more nimble than you would expect [Music] to get off the ground quickly and to stop suddenly pigeons literally clap their wings squeezing the air to produce a huge thrust either forward or backwards it’s like some old cars you know turn over the engine or you can recognize the gearbox or whatever with the pigeon you can hear it and it makes this clattering sound as it comes in to land or it takes off what they’re doing is that when they’re clapping their wings together like that they’re creating massive vortex that really gives them a big shot forwards which is great for braking when you’re coming into land and actually getting the power to get going today wildlife cameraman Jonathan Watts is trying something that hasn’t been done before with a unique harness and a high-definition camera this pigeon is about to give us a bird’s-eye view once in the air they’re nimble and fast watching them skim over the urban landscape pigeons look like masters of their environment that great eyesight that helps them dodge traffic on terra firma is essential up here where it’s just as dangerous eyes on the sides of their heads allow the birds to see almost all the way behind them exactly where a hungry hawk or Falcon is likely to be [Music] when frightened visions will go into a tight formation in the air making it harder for a predator to target a single bird [Music] another clever strategy is playing dead at the height of the chase a pigeon can go into freefall luring its enemy into a dangerous game of chicken these are the first shots of this kind ever taken on a pigeon in flight a pigeons world is a dangerous chaotic place slowed down to show how they may see it however it can seem almost serene [Music] how pigeons find their way home from places they’ve never been has long been one of the great mysteries of science until now [Music] despite a reputation as a dim-witted nuisance pigeons are super smart they can be trained to recognize the letters of the alphabet they can spot stranded boats from a distance even their own reflection in a mirror they’ve played the role of hero forever sending messages back to the front lines in war delivering emergency medicine from one hospital to another carrying critical mail and even secret messages between investors on Wall Street once you realize that then if we wanted to communicate with each other we both had pigeons I would give you some of my pigeons you’d give me some of yours we could we could keep these pigeons and then when I wanted to send you a message I would pick one of your pigeons and just release it and we go directly to your pigeon coop [Music] pidgins show up in some of the oldest records there are Egyptian hieroglyphics Mesopotamian tablets from 5,000 years ago they were messengers in battle for Julius Caesar and Genghis Khan they delivered the results of the first Olympic Games the ones you see on city streets today are descendants of domestic pigeons who either got lost or were let go around the turn of the century people lost interest in these pigeon coops and just released their pigeons and they eventually the pensions made it to the to the cities or downtown and that’s where they managed to survive and so a lot of them are are still living in these downtown areas I think because they find ledges that correspond to their native habitat which was cliffs on the on the edge of the season [Music] the glory days for pigeons are long gone their noble perch long forgotten today these scruffy urban birds are known more for the mess they leave behind instead of being celebrated they mostly face contempt or worse as scavengers pigeons are constantly looking for sources of food but just how far and wide does this search take them how much territory do they actually cover on an average day we tried to find out actually what is the home range of these particular pigeons here in this neighborhood using a group of birds that have been trapped in a central Toronto neighborhood professor Dmitri kishka Nev from the University of Guelph uses the latest in GPS technology to track the birds move for a normal day and this is a fancy new technology that this is I think refers them somebody tries to apply it so feral pigeons it works just like a cell phone but GPS devices and once both things are working then we can receive coordinates as text messages for example or we can see them on in the app on our cell phone matched up with Google Earth the system will give us a minute to minute map of where a typical pigeon goes over the course of a day so we’ve done everything what we can do now and ready to go [Music] [Music] actually it’s very funny because you can you you have a cell phone number for this device it means that you basically call the bird and you can hear how the bird is behaving and how it’s making noises so this is pigeon number two [Music] after tracking the birds for a day dimitri discovers their range of movement is fairly small but that they don’t sit still for long the pigeons all stay within a few block in central Toronto but the average total flying distance was 40 kilometers wherever people routinely feed the birds is where they’ll live out their city lives often around a specific park or intersection but pigeons also have an amazing ability to navigate long distances even from places where they have never been how pigeons actually navigate their way around has been one of the great mysteries of science for centuries [Music] there’s a remarkable annals you take them anyway let’s pop them in the car put them in a dark room drive 100 kilometers and the fly more or less straight home how do they do that there are a few theories for how pigeons do this professor Verne Bingman from Bowling Green University has joined some colleagues in Winnipeg to see if they can get some definitive answers what does the environment offer that can inform these birds on where they are with respect to home from two hundred three hundred four kilometers when they are not in sight of anything they’ve ever seen before and historically the most attractive hypothesis that in some way these homing pigeons rely on some variation in the Earth’s magnetic field an ability to read the Earth’s magnetic field so the theory goes tells the birds where they are and in relation to that position the direction of home so we’re trying to figure out today is we’re going to actually disrupt the birds and so if they have this magnetic map sense that we see that many people think they might have and what we’re going to do is going to we’re going to blow it up we’re going to interfere there’s their magnetic sense by attaching a very strong magnet to the beak now the reason why we’re doing this on the beak is that most people believe that F these birds have a magnetic map sense it’s mediated by these receptors that are located in in the beak area okay and these and these receptors then will pick up information from the Earth’s magnetic field and of course transmit it to the brain so if they have a magnetic map when we let them go they should have a hard time getting back once the magnet is secured a GPS device is also attached so the bird’s flight path can be monitored in detail for any deviation from the most direct route back pigeons are also known to use landmarks to find home but that requires they’ve seen them before the other leading theory for how the birds navigate over distances is that they use their sense of smell so this is going to be our second experimental manipulation where we’re going to rather disrupt their magnetic sense we’re going to disrupt their olfactory sense and the way we’re going to accomplish that is we’re going to be using a local anesthetic it could be something called a Ginga ie NORs I’ll Akane it’s just basically the kind of stuff that you put on babies when they’re teething to kind of numb the gums and we’re going to go into the olfactory mucosa and we’re going to give a couple of shots into the right nostril a couple shots in the left nostril this will temporarily anesthetize the olfactory mucosa and interfere with their capacity to sense atmospheric odors and if atmosphere coders are important for these births get back and we should see some kind of disruption in there and they’re in their flight back home their of their path home [Music] together with a handful of other birds that have not been altered in any way the pigeons are loaded up in a crate and driven miles away from their home base somewhere where they have never been before and released whoever makes it home first may go a long way in answering one of the great mysteries of science how do pigeons navigate [Music] [Music] this is the really the fun part the the pigeons are back we were got the GPS recorders we downloaded the data and then now we’ve plotted the data and which is basically the track the pigeons the paths of pigeons took back to the home off back in Winnipeg professor Verne Bingman is ready for the results of an experiment into how pigeons navigate one of the test birds has had its ability to read the Earth’s magnetic field altered by placing a magnet on its beak another has had its capacity to sense atmospheric odors interrupted a third is left unaltered the first the first track that I’m looking at right here is actually the control bird the unmanipulated bird that we let go and this point is the release site and this point is the home loft and what you can see is a typical pad and this is not unusual the birth takes off it flies a little bit around the home loft and it basically heads and goes home and pretty much a straight track I mean it’s a homing pigeon that’s what they do that’s what we expect them to do now let’s take a look at that magnetically manipulated bird see if it’s done anything interesting the main effect of this magnetic treatment in this particular day and this particular bird is that when it departed left in a somewhat different direction from the control animal but it quickly corrected and headed straight towards home so there’s really not a lot of evidence here that the birds have a magnetic map because that does very disruptive magnetic field really didn’t interfere with their capacity to come back home very very quickly a second bird has had its ability to sense odors in the atmosphere temporarily impaired now what’s very exciting as the results from the olfactory bird bird that we anesthetize the olfactory epithelium if you look at this bird and you can see it’s having an absolute miserable time so again here’s the release site this is where the bird is going and you don’t need it to be a statistician you really don’t need any training really in science to see that this bird is literally flying all over the place it’s very disoriented and it finally takes off and it probably when it gets near to the loft and start seeing familiar landmarks and sentence able to use some alternative spatial information some I’ll turn navigational information it’s able to eventually get back to the loft but this initial phase of the homing flight or the animal is going to be using its map sense it’s having an enormous ly difficult time okay and again what these numbers are saying with these these this figure is saying is that positional information is based on odors okay and that’s why they’re so confused incredibly what these animals learn is how different odors are distributed in space basically the odor profile of the atmosphere varies predictably in different directions so then when you displace a pigeon to a place that’s never been to before and somehow comparing the odor profile at the point of release with the odor profile at the home loft and is then able to determine its direction displacement have I been taken east have I been taken West I’d have been taken north and I’ve been taking south once it attracts that positional information based on atmospheric odors smells and it really is smells then they rely on this directional system I don’t want to pretend that olfaction is the only answer to the challenge of navigation but what I can say confidently is that olfaction atmospheric odours is the only demonstrated reliable source of navigational information that these pigeons can rely on it’s because of this amazing ability to navigate that pigeons became the first animal on earth to be domesticated for almost as long they’ve also been bred for show from royalty to celebrities to working people pigeon fanciers as they’re known take their hobby very seriously [Music] in Canada alone there are over 5,000 fanciers who love nothing better than getting together on the weekend and showing off their birds [Music] we’ve taken it to a whole nother level or where we’ve developed birds that aren’t even close to what the feral pigeon is anymore this is an intense hobby of selectively bred birds that have evolved over thousands of years into something that has suited the taste of each individual reader with over 2,000 unique looking birds on display here at the canadian pigeon fanciers national exhibit the country’s top breeders are competing for their own best-in-show you’ll find probably more variation within pigeons than any other thing I am familiar with dogs as another thing was an awful lot of variation and the two of them proved that basically whatever you select for you can achieve well it may look like a frivolous hobby Clint and his colleagues are actually an esteemed company in fact fancy pigeons were used to demonstrate Charles Darwin’s theory of natural selection in the Origin of Species the seminal text on evolutionary biology so Darwin was very interested in seeing where things were evolving Darwin was able to observe the fact that there was a fair amount of variation in pigeons the great variation within pigeons was in fact the very foundation for his understanding of how evolution works selective breeding is is what the pigeon hobby is all about it’s it’s challenging our skills as breeders to create a genetic work of art [Music] so they can select for color is one thing they will select for they can select for shape and size feather structure would be another one you’ll find some birds have got large tails you’ll find some we’ve got feathered feet you’ll find some that have got a crest on their chest or their neck some will have different shapes of beaks all kinds of what I’ll call ornaments so whether that’s a crest on top of their hand a shell lots of different things can be done just like dogs and horses pigeons are also bred to race the big difference is the pigeon racing for a lot of us flies under the radar the drama and the stakes can be just as high single Birds trade hands for hundreds of thousands prize money in Canadian competitions is modest but it is a big-money sport in other parts of the world the premier event is the South African million dollar race the sport has even had its own theft racketeering and doping scandals well in Europe Belgium Holland Germany yes I’m that stuff’s been done they’ll feed them steroids and we don’t do that if we ever knew anybody in our in our organization did that we would kick him out of the organisation here in Canada generations of European immigrants continued a tradition that his centuries-old I was born basically in the country and every kid around the neighborhood had dogs cats it was chickens there was rabbits and pigeons everybody had them when I was a kid and it was strange for somebody not to have them where I loved [Music] in our calm mind we fly them from anywhere 100 miles to 550 miles a dump it and eventually we’ll make it home but he won’t make an old fast enough to win a race see our breeding for intelligence orientation ability we also want a good-looking begin just like us or a red racehorse you want a good-looking horse they can run you want a good-looking pigeon they can fly pigeons like these from all over Ontario compete every weekend from a single release point they take off for their respective home lofts their arrival times are logged electronically and compared whoever had the fastest average speed is that week’s winner we give them had it was like you would not believe my birds get in in the water they get garlic for instance which is a antiviral thing it helps any viruses or whatever and they get oils put on their food I spent a lot of money on flaxseed oil and hemp seed oil and that’s that’s to build up that on them for fuel to fly this weekend Bruce’s fastest birds are getting loaded up for an early-season race his pigeons will join 1,500 others from around Ontario at a collection point north of Toronto from here they’re off to a release point in Berks Falls about 250 kilometers away tomorrow morning if the weather holds they all get released at once and the race for home is on [Music] well tonight we’re gonna take my pigeons to live the Humber Valley Racing Pigeon Club how’s our weather tomorrow mr. redditors through a half-decent pigeon man you’d already known you wouldn’t have to ask that start and we’re gonna scan my pigeons through a electronic scanner into a computerized claw and that’s gonna tell us what time those birds were scanned and the day they were scanned from there we’ll take them to a collection area and they’ll get loaded on a trailer that’s specifically designed to transport pigeons when we load them on that trailer that traitor will go from that collection point to Burke’s Falls [Music] in Burks Falls 1,500 pigeons are set to be released at the same time [Music] after getting its bearings each bird will take the most direct path it can back to its own loft where arrival times are meticulously recorded and compared until a winner is declared based on the average speed over the total distance [Music] back at the loft Bruce is eagerly awaiting the sight of his Birds generally the average flyer and most of us race for nothing just for the satisfaction the fun of having our Fitness come on a classic Upstairs Downstairs narrative the life of the racing bird is worlds away from their poor city cousins downtown it’s just another punishing day in the epic battle to survive the urban jungle we forget when we see them now just how much pigeons have done for us in the past we’re still asking for more like rats they’re often used in critical studies related to learning and cognition in the lab elderly pigeons like some humans can find themselves getting lost in familiar environments because the birds encode spatial information the way we do and can lose their navigation skills as they age they’ve become a very important research tool in the search for a cure for Alzheimer’s pigeons they were among the first animals used by experimental psychologists to study learning they can’t be too dumb if if they’re the major animal that’s used in the lab to study the learnings for thousands of years we have shared the human experience with pigeons relying on them for everything from food to vital communications to entertainment to modern day brain science still as a society our respect has been withheld I don’t think pigeons get very much respect in the animal kingdom but I think they probably should I think people just are uninformed as to what pigeons are capable of and how adaptable they are and what feats they can perform that other animals can’t you know they’ve served humanity really well people often think of dogs as serving Humanity or monkeys that went up in space but you know pigeons have been there too so pigeons have been there for us and we shouldn’t let them down they they actually played a really important role in our history [Music] meantime in city streets all over the world the treacherous precarious life of the pigeon marches on the notion of the bird brain is quite now it’s not even taken seriously anymore in terms of feral pigeons by default their success is undeniable if we consider what a feral pigeon is confronted with the distribution of resources a complex three-dimensional landscape that these animals needs to navigate through live we find food it reflects it an ability to adapt to very extraordinary situations their ability to evolve and think they find places to nest and they find food sources whatever it might be and they manage to raise their young ones in the harshest of conditions because the male and the female work together and as a pair they’re loving devoted parents and it’s really amazing when you think of how they’ve managed to survive the fact that pigeons can survive in an urban environment that is designed to exterminate them at every turn means that they are pretty much the ultimate survivor in the cities born wild today they are essentially domestic and utterly dependent on us a lot like our cats and dogs but without a permanent address [Music] individuals yeah identical twins are a treasure trove for scientists twins are the only real unique natural experiment we have in humans while twins can be remarkably similar people ask why me when they get sick I ask why hurt researchers are probing their differences for clues to all kinds of medical mysteries I think nature versus nurture was it is bilking us out of billions the internet has breathed new life into old scans $500,000 of mortgages have been picking up in my main con on dr. next on CBC price wars men’s versus women’s products you are not gonna win this battle I’ll see you so how about your yours six dollars and 22 cents these are 998 women should not be paying more for something that is essentially the same marketplace Friday at 8:00