this is bbc news. the headlines — a former senior executive at twitter, peiter zatko, has presented allegations to the us regulators claiming that the online platform misled them about security problems. he has said they placed personal user data and potentially us national security at risk. twitter has denied the allegations. washington is set to announce its largest single, military—aid package for ukraine — as the country prepares to mark independence day. the united states is also urging its citizens to leave ukraine — after warning that russia is planning to step up attacks on civilian buildings around independence day. polls have closed on a day of primaries in several us states that could set the tone for november's mid—term elections.

the democrat representative, charlie crist has won the primary in the us state of florida — while counting is taking place in oklahoma and new york. now on bbc news, on this week's travel show, lucy hedges heads for the big outdoors, as the usa celebrates the 150th birthday of yellowstone national park. on herjourney, she encounters grizzly bears, wolves and bison, as yellowstone looks for new ways to work in conjunction with native american tribes. this week, i'm taking a journey across yellowstone national park, as it celebrates its 150th anniversary. oh, my god. just spectacular. i will meet the people using this milestone to address the park's complex history, by returning america's largest land mammal back to native american tribes, in an historic partnership.

the ecological importance of restoring animals to the landscape heals the land. by integrating this animal back it heals us. i will attempt to track down the park's elusive wolves that were reintroduced during one of the most successful rewilding initiatives of all time. it doesn't happen too much in human endeavours where your ancestors have made a terrible, terrible mistake in terms of killing off wildlife that you can correct that mistake and make it better and that's what happened here in yellowstone. it's a very positive story.

yellowstone was one of the world's first national parks. established in 1872, it inspired a movement, and today, there are thousands of them, globally. lakes, volcanoes, and mountains span almost 4,000 square miles of wilderness. home to over half of the world's active geysers, the park is at the core of one of the largest ecosystems on the planet. so this is old faithful. probably one of the world's most famous geysers. and there she goes! oh, my god. it's just spectacular.

the snow—capped mountains in the distance. it's hard not to drive with yourjaw open, basically. and the first stop on my journey is the park's oldest lodge, as it opens its doors for its busiest season yet. yellowstone represents some of the very best america has to offer, and 150 years is a long time. we didn't always get it right. we killed every single wolf in this park. even in the 1960s, we were feeding bears out of garbage dumps. despite fierce opposition, when the park was first established, indigenous people were forcibly removed from their land. until now, their history has been largely untold,

the park service is trying to change that. so, 27 american indian tribes that, to one degree or another, were on this landscape prior to 1872. and even though we have done some really good things with tribes over the years, we felt that it was a point in time where we really needed to re—engage the tribal nations. yeah. and for us to not only be able to tell the stories ourselves about american indian history and culture — which is part of our mission — but also to get them in the park... yeah. ..to get them engaged with visitors. and so we've done it. oh, it takes me about four or five days to make a doll. wow. back inside, i meet scott, whose native american ancestors were forced from their lands. he's here not only to sell his handicrafts, but also to later raise his

tribal flag over the site. this song is my brother's song. it's a sun dance song. it's to wake up to. sings. so, raising the flag to me is, you know, coming home and putting the flag in and reclaiming, you know, what was — to some — taken away. yellowstone calls out to people to come, worldwide. somehow, that word "yellowstone" is a message to people to come and see not only the geysers, but the animals, you know? the buffaloes, the wolves. and so, for me, it's a beacon... yeah. ..of starting an environmental movement to save land for us in the future, but for us to come in to be with the people — the animal people.

and it's the animals that are helping soothe these relations — in particular, yellowstone�*s iconic bison. these days, you don't have to travel far to come across these guys thundering around, causing trafficjams. but at the end of the 19th century, they were hunted almost to extinction. in a short space of time, the population of america's largest land mammalfell from over 20 million to around only 200 and, with them, disappeared the futures of many native american tribes. it was really a sad story. we thought that removing bison from this continent was the way to remove the food source that native americans relied upon. and as we were essentially eliminating native americans from this country, we were eliminating their food. and it's taken us probably 100 years to come to grips

with that and then to say what it really does mean to get these animals back out on big landscapes and, more so than that, hopefully get them back to people. these animals mean more to them than maybe anybody on the planet. yeah, yeah. thanks to a captive breeding programme, bison numbers are now booming. coming now — one, two! and, for the first time in its history, the park authorities are working with local native american groups to relocate these magnificent beasts to roam again across tribal lands. here she comes — five! we get in the truck, i'm usually behind the animals as they're heading north. you know, we have these caravans of trucks just heading

across the highways of montana. and it doesn't matter what time of year it is, the tribes are just waiting there, they're waiting for these animals to get off of the trucks. back on the road, i'm making a five—hourjourney to see how one of the latest herds to be released are getting on. so, i've now left yellowstone behind, i've entered the wind river reservation and it feels really, really different here. wind river, one of the largest reservations in america, home to the eastern shoshone and northern arapaho tribes, was created when conflict broke out between the tribes and european settlers in the 19th century. hey, jason! hi, how's it going? i'm good! how are you? jason is the man responsible for the newly relocated animals. hello! along with the breeding programme, he also hosts local school groups to try and reconnect children with their native american heritage.

so, how do the kids respond when they come out here? it's in our genetic memory, you know, buffalo are in our dna. we had some kids come out in a bus and they got off the bus and the buffalo were curious and they came around the bus and to see them make eye contact with each other was something really, really special. it's an emotional experience, really, you know, to see those kids have a reconnection with that. yeah. it never gets old. never. no, they're such gorgeous creatures, aren't they? they are. drumming. so talk to me about the moment that the first buffalo hoof hit the land. it's taken me 15 years, really, to get the supporters — a bald eagle flying over us right here. gasps. bald eagle! it was very impactful.

you know, you could never imagine thatjust that one hoof print would have been so significant. yeah, yeah. but it was 131 years that it took for that hoof to land. so, beyond conservation, you know, why are the buffalo so important? that piece of our life, connection, was severed when the buffalo was eliminated... yeah. ..nearly exterminated. so, restoring the animal to our communities is very important and our cultural revitalisation. yeah, yeah! you know, the ecological importance of restoring animal to the landscape heals the land. by integrating this animal back into our diet, it heals us. i myself had to find that — i struggled with alcohol for a number of years and was able to put that away 3.5 years ago, find recovery, find healing. yeah. it's putting away, you know, the atrocities, the problems that were imposed upon us and creating a new solution to something better.

yeah, yeah — the buffalo have really helped you find yourself and just reconnect. i wouldn't be here today without these buffalo. jason, you are making it happen. the work you're doing here is, honestly, nothing short of incredible and i wish you the best of luck with everything, from my heart. well, thank you very much. i genuinely mean that. thank you very much. the bison transfer programme is growing — but slowly. transporting these animals isn't easy. montana laws limit movement forfear of transmission of disease to healthy livestock. the impact of state law can be felt throughout the park, particularly where i'm going next. gardiner is home to around 800 people. and one of the main industries here is taking visitors out to try to try and spot the illustrious wolf.

it is obscenely early. i've got to tell you, i am not used to waking up at this hour. but we could be seeing wolves today. so let's hope the wake up call is worth it. recent and controversial changes to the law have increased the quota of wolves that can be hunted outside of the park's boundaries, potentially placing these majestic animals under threat. making the work of yellowstone forever increasingly important. hi, amanda. hi, good morning. amanda works for the park's not—for—profit partner to support vital conservation in the area, including keeping track of the wolves. today, we're going to a special part of yellowstone, called yellowstone�*s northern rim. the special part about this is this is the most wildlife—dense part of what is already one of the most wildlife—dense places in the continental united states. even though this is only 10% of yellowstone, this holds 50% of yellowstone�*s wolves. but that hasn't always been the case.

in the early 20th century the wolves here were wiped out by hunters. so people came out here, european americans, specifically, came out and waged war on predators. though it seems yellowstone is a park of two poles, and 27 years ago, wolves were controversially reintroduced to stalk through the valleys once more. it was the first ever attempt at releasing these predators, and remains one of the greatest rewilding stories of all time. i'm just hoping that we really see wolves today. it's been a long drive, we've been out early, so the pay—off has to be wolves. and as if on cue... radio: where are you now? just passing elk creek. amanda, he wasjust

telling you he was down the camp ground road. right now, those wolf packs are going to be focused around their dens and caring for their puppies, and so for one particular wolf pack, they're considerate enough to have their den site pretty much within view of the road. there's a lot of cars here, what's going on here? it looks like a lot of people are out today, so hopefully that means the wolves are out and about. there is a name for the people who come and watch wolves every day — wolf watchers, and there are plenty of them. one in particular is ready to show us where to look. the blackest coloured, i think it's 12:29, a two—year—old female. rick has been watching wolves almost every day for almost 20 years. we've been here for about five minutes and we've already spotted a wolf. it keeps popping behind

trees and behind rocks, but hopefully i'll see it in a moment. it's a grey wolf! given the wolves were pretty much wiped out here, it really does feel special to see them here just running in the wild, and it's actually quite strange to think of yellowstone without wolves being in here, it's very much part of the territory. i get the sense that rick is somewhat of a local legend. what is it that keeps you coming back, to get up early and check out the wolves each day? well, i'm almost at my 9000th day of being here looking at the wolves in yellowstone. and so i never get tired of it. every day i want to get up at 3am in the morning and come out here.

yeah. there's never been an opportunity like this in human history to study the wolves the way we are right 110w. so just yourself this morning, you got to see tiny wolf pups coming out of their den. idid! you probably had one of the best sightings of adult wolves and pups compared to many biologists in the world. it doesn't happen too much in human endeavours — where your ancestors have made a terrible, terrible mistake in terms of killing off wildlife, that you can correct that mistake and make it better, and that's what happened here in yellowstone. it's a very positive story, very optimistic story. a story that seems to bleed into every part of park management today. partly thanks to these wolves, the ecosystem is now back in check, which might have had something to do with my next stroke of luck. on this seemingly endless parade of some of the world's

most revered mammals, i stumbled upon this. driving along, i saw loads of people were parked up looking at a certain direction. i asked them what they've seen. and right over there in the distance is a grizzly bear! from what i understand, it's quite rare to spot a grizzly in the wild, so this is a very special moment, i mean, this is why you come to yellowstone, right? but it wasn't too long ago that visitors like this would have been behaving quite differently — where the wolves were a pest, the bears were a source of entertainment. voiceover: by the late 18005, bears had figured out that - where there were people there was food. for the next 80 years, a hallmark of every yellowstone visit was looking for bears begging along the roadside, or watching them feed on food scraps at the hotel garbage dumps. thanks to research, we've come a long way since then. while close encounters

are rare, with over 700 bears in an area, that is becoming increasingly populated, it's important to be prepared. randy! hello. i'm heading to west yellowstone to meet randy. he runs courses in bear safety, but he doesn't work alone. 0k! this is the bear? yeah. talk to me about how you use this to teach people about their safety. well, if you are not able to avoid an encounter with a bear, bear spray is the most effective thing you can use to change a bear�*s behaviour. if you get this hot pepper oil that is in this container into their face, they're going to forget about you, and that you might be a threat to them, and are going to want to go somewhere else. most of the encounters we have with grizzly bears around here, they�* re defensive encounters. so you're going to growl, they will drool, they will huff and make different noises, they will stomp on the ground.

so it is good to have this strapped to your belt all the time? yes, things happen really fast. the nice thing about this training device is that it goes at about 20 miles an hour. a real bear goes about 35 miles an hour, which is quite fast. so this really gives people an idea of how quick they have to be to get the can out, switch the safety off. i had no idea they could move that fast. oh, yes. all right, we've assessed what the bear�*s doing, it looks like he's going to charge. we've stood our ground, we've got our spray out. oh yes. time to take safety and when he comes, straight out in front of him for a couple of seconds, a couple of bursts, until he changes his behaviour. gotcha. right, here he comes! wild west music. very good. even i know that's a mechanical bear, i was like — phew! it gets your blood flowing. one things for sure is that i shouldn't need my spray

where i'm going next. down the road, a group of dedicated individuals are working on methods to decrease the amount of bear encounters in the area, with the help of the bears themselves. keeping bears away from food ultimately helps keep the bears away from people, so when camping it's so important to stash your food safely. here on the outskirts of yellowstone, they're actually testing the sturdiness of food containers by putting them up against actual bears, and needless to say, these ones didn't quite pass the test. we have put some dog biscuits in there so that it rattles around. there's peanut butter in there, an old fish as well. it's got to withstand a 60 minutes of direct contact from these bears, but if it does it can be certified as bear—resistant by the interagency grizzly bear committee. so you can see... look at those claw marks! ..obviously attention from the bear — teeth or claw marks there.

they're pretty deep. teeth marks. yeah, so tell me, where did these bears come from? grant is actually from yellowstone national park. coram is from glacier national park. so they were wild bears that got into trouble with people. that doesn't happen just out of the blue, it really happens when bears get food rewards. and his last act as a wild bear was to climb into somebody�*s vehicle in their own driveway in the middle of the day while they were trying to unload their groceries. sadly, not all the mischievous bears can be rehomed here, and around a0 are put down each year. so in the case of the eight grizzly bears that live here at the grizzly & wolf discovery center, we have provided an alternative, but maybe even more importantly we get visitors in the area a chance to learn from their stories, even though they're still getting into conflicts with people over food, the population is much more stable than it has been in the past. and a lot of that is

because what we have learned about how important it is in that country to be careful with our food, and the techniques we have like bear—resistant containers for securing that food. the effort being made to educate visitors on how to protect the ecosystem for the future is undeniable. back at the lodge where i started myjourney, it's scott's big flag raising moment. this is the crow tribal emblem. it has the great seal of the crow tribe. it's a very great honour, you know, to come and do this for the tribe and the people. a really great honour. for the crow people and all the native people who've never left this country. seeing these two flags flying alongside each other hopefully signals the start of something

new, more respectfulfuture where, although the wrongs of the past are acknowledged, everyone who lives and works in yellowstone can look towards a more respectful, more positive future. and what better way to mark this truly astounding national park's 150th birthday than that? hello, there. there was a lot of late august sunshine to be found on tuesday. it was a beautiful day across much of scotland, as you can see from highland, but here, temperatures sat in the high teens, low 20s.

now, further south and east of that, again, lots of sunshine, but it was hot and it was humid with it. in fact, suffolk saw the highest temperature on tuesday afternoon of 29 celsius. as we move into wednesday, this weather front will produce some rain, but it's also the dividing line between fresher air to the north and west and somewhat humid conditions continuing across much of central and eastern england. so, yes, we will see some rain, some of it heavy at times across west wales and then gradually pushing into north west england. a few isolated showers further north and west, but here it will be predominantly dry, breezy as we go through the day, but those temperatures once again sitting in the high teens, maybe low 20s. to the south and east of that weather front, our temperatures again on the high side, 25—30 degrees, and it will be very humid with it as well. now, as we move through wednesday evening, into the early hours of thursday morning, our weather front doesn't move very far very fast, and when it does so, it will weaken off considerably. so a band of cloud and a few patchy showers moving across the pennines, but to the south and east

of that, there's a risk of some thundery downpours developing in the south—east. and with the temperatures staying on the high side, 17 or 18 degrees, some of those showers really could turn quite heavy and thundery. so during the early hours of thursday morning, we could see across essex, kent, suffolk and maybe north norfolk some sharp showers drifting their way steadily eastwards. they will be fairly isolated and only on those eastern fringes, but any rain in these areas is certainly going to come as welcome news. cloudy skies following on behind, brighter skies behind, with a scattering of showers in the far north—west. noticeably fresher for all — 15—24 degrees the high as we move out of thursday. now, friday, into the start of the weekend, sees a weather front push into the far north—west and the wind direction changing. so it looks likely that the far north could stay cloudy with outbreaks of rain at times, potentially. elsewhere — and, yes, it's a bank holiday for northern ireland, england and wales — dry, settled but fresher.

welcome to bbc news. i'm david willis. our top stories — washington is set to announce its largest single, military—aid package for ukraine, as the country prepares to mark independence day. twitter�*s former security chief says users' personal data has been put at risk, along with us national security. the company denies the allegations. a key day of primaries in several us states that could set the tone for november's midterm elections. charlie crist has won the democrat primary in the state of florida. days after deflecting accusations of an excessive party lifestyle, the finnish prime minister apologises for an "inappropriate" photo of guests at her official residence.

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