>> announcer: this is "nightline," vanishing ice. inside the melting arctic circle. where the elusive polar bear is clawing for survival as their environment disappears beneath their feet. these powerful killers are moving inland towards humankind and fiona the hippo born premature and unlikely to survive now a bona fide celebrity with millions watching her learn to swim and take her first steps. then it's off to the amazon to find the beautiful and rare pink dolphins. how scientists are working to bring their numbers back. and later, the safari continues in nairobi, kenya, where hotel

guests are up to their necks in giraffes, the gentle giants butting into bedrooms, even pan >> i usulyon't kiss on the first date. >> this is a special presentation of "nightline," "into the wild." here now juju chang. >> hey, everybody, thanks for joining us. we'll begin with the journey to the edge of the earth where americans are under increasing threat from polar bears. now moving inland in search of food as their habitat and numbers dwindle. amy robach is with scientists racing to save this vulnerable species. >> on the pure white ice they are almost invisible. an enduring symbol of the wild arctic, but in recent years the polar bear has come to embody something else, a creature caught in a changing world that is disappearing under its feet.

there are less than 25,000 polar bears left in the wild and few ever encounter them but each year dozs ded on this isolated alaan village. on a y what is pushing these elusive beasts closer to people. >> you're going to fly right over the arctic circle up to barter island. >> welcome aboard. >> hi. this is day three of travel and have our fingers crossed because we're hopeful we're actually going to get up there today to see the polar bears. here we go. >> we'll check our latitude on the gps and, yes, we have just crossed the arctic circle so the brooks range is ahead. they're extremely rugged as you'll see and extremely remote area.

>> so remote we lose contact with air traffic control. >> we have to radio communication with the outside how dicey can it get up here. >> you have to be question comment especially as remote as we are. >> but even from this vantage point, our co-pilot says evidence of a warming planet is visible. >> glaciers are receding. the sea ice has shrunk. s substantially. permafrost has started to shrunk but things are getting warmer. >> approaching barter island we get a preview on the stoney aisles below, a white bear. >> wow. that's so cool. >> 15 southwest of barter island 1,000 feet inbound planning runway. >> well, we finally made it. the village of kaktovik,

alaska, population caarand striki t quit blankght . a change that is reaching into all corners of life here. it's not long before we see what we came for. we left the shore three minutes ago and already there are four polar bears right there swimming in the water. that's incredible. wow. i mean, what are we, 50 feet from them? we're pretty darned close. one, two, three, four polar bears. a mother with her triplets. these bears a drab shade of brown wearing the signs of spending so much time on muddied land. >> wow. so you often see them playing with each other. >> every day. >> every day. >> our captain bruce says these bears are here because they are waiting for the sea ice to return.

the frozen surface of the arctic ocean where they spend most of the year feeding on seals. >> they're just conserving energy.ey got a long itth investigate on the remains of the bowhead whale, the people there must hunt them to survive here. >> unlike the polar bears linger or stay around these parts. >> every year the fall time, they'll hang out here until it's mid-november and then they'll -- when the ice starts forming out in the ocean, when that starts happening the seals go on the ice and that's where the polar bears get their seals, on the ice. if that ice is not there they don't get nothing. >> the bears used to spend just three weeks on land. but today they are stranded for nearly three months because the ice is staying melted longer. scientists say it's due to global warming. in this part of the world the te

of 9% a decade. a dramatic number for polar bear conservationists. scientists dr. todd atwood and his team tranquilize them from helicopters collecting samples. >> does it look like a male? >> studying how climate change is affecting these bears. >> helps with warmth and friction, i think. traction. those beautiful claws. >> we spend about 45 to 50 minutes with each bear that we capture and collect a variety of samples. a bunch of body measurements to measure physical stature and how it might be changing through time. probably right on the cusp of being an adult and we gave him seven ccs which is the standard dosage for a bear of this size. i think the most surprising thing for me personally has been the complexity of their behaviors, you know, we've seen them adapt to some pretty

dramatic changes in the arctic sea coast system and seeing them use terrestrial habitats that we didn't expect them to use and switch to certain food items that we didn't expect them to switch to because we can characterize stress using hair samples and we can relate that to how the environment has changed around polar bears to determine if those environmental changes are increasing stress levels. >> currently polar bears are categorized as a vulnerable species meaning they have a high risk of endangerment in the wild. >> looking for polar bears out here on the sea ice is about learning to read the signs of their passing and just here behind bes. >> in most places of the world,

polar bears are incredibly difficult to find. >> it's a rare sighting. >> the grueling hunt demonstrated in the documentary "ghosts of the arctic." but here the direct access and sheer number of bears has sparked a tourist boom. visitors like ed bennett fly in hoping to snap the perfect picture. >> what maybes it worth it to me is simply seeing a beautiful white bear walking along a beach who's basically here only because the ice hasn't frozen yet. ice that would have frozen years ago. >> here we are unbelievably close to these bears. stopped running. so cute. oh, he's looking right at us but thankfully the water offers us some security. >> we're safe on the water. >> we're safe on the water. gd boat. >> on land it can be a different

story as bruce knows all too well. >> this happened. i was standing beside him for about a good three seconds. >> you didn't even know he was there. >> i didn't know he was there. >> he was so quiet. is that the most frightened you've been in your life. >> yeah. >> i would think so. >> the opportunity to get a closer look on land is too tempting. so as twilight falls we set out by suv. >> that's just spectacular right there. it's so pretty. to the bone pile where the hungry polar bears feast. >> we are here right by what the locals call the bone pit and that's where whale character casts have been left for years and years and years and the polar bears come at dusk and feed on what's left of the bones. our guide tells us we can get a few shots but we have to be ready to make a quick escape. we were told we could go et out of the vehicle as long as we were near the vehicle and if we heard him say get in we had to run. no hey, i need one more shot or i almost got what i need. he said you'll have to run

straight back to the car. you just don't know where they're coming from and they move very quickly so we would have to move very quickly as well. though these bears are cute they can be deadly. in 2013 a bbc wildlife photographer captured this sheer power of a polar bear attack from inside a glass case. >> one of the most powerful animals on the planet. one of the most intimidating and one of the few that see us as food. >> the male bears can weigh 1,500 pounds and stand at over nine feet tall and charge at 25 miles per hour and their bite force is an astounding 1200 pounds per square inch. though all they need to kill is one swipe of their massive paw. i see some over there too. standing so close to these powerful creatures is awe-inspiring but our guide says it is a bittersweet opportunity. >> when i first came here, the pack ice was in sight of the shore all summer. now there's 150 miles of open water and more in some places. >> that has a huge impact on the polar bear. polar bes here.way.ve a lot of

this beaufort population is now down from 1200 to 900 in the last 10 years and have been hunting whales for probably 10,000 years so they're not coming here because of the bones, the remains of the whales that we catch. they're coming because the habitat is going away. the world should be interested in this. >> while we're at the bone pile. >> right over there. >> we become nervous these bears are interested in us. >> there is momma polar bear with her two cubs, not that far from us walking through water on a piece of land that's connected to us. pretty close. >> freakishly close. >> wow, look at that. >> stay with us. whole room smelling like sweaty odors. yup, he's gone noseblind. he thinks it smells fine, but his mom smells this... luckily for all your hard-to-wash fabrics... ...there's febreze fabric refresher. febreze doesn't just mask, it eliminates odors you've... ...gone noseblind to. and try febreze unstopables for fabric. with up to twice the fresh scent power, you'll want to try it.... indulge in irresistible freshness.

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>> announcer: "into the wild," a special presentation of "nightline" continues.

in the remote tundra they're stalking damage dangerously close to us. but thankfully mother bear seems to decide whale meat is a better dinner. once in a lifetime. as night falls, our guide robert thompson shows us evidence of a threat we may not be able to escape, signs that the climate is changing. >> you can see where the permafrost is melting. you see the ground cracked over there and it's open. and when it melts more and the water flows out. the fence was here years and years ago so the wind wouldn't blow it over. they had metal stakes that were driven into the ground. now they're melting, and they're not holding the structure up anymore. >> this shows you that the permafrost is melting. it's not permanent.

>> reporter: the coastline isn't permanent either. erosion has affected much of alaska's arctic coast, chipping away at beaches, threatening towns and habitats. >> you love this land. >> oh, yeah. >> how does it feel to see the changes that are happening? >> well, i think -- i think the rest of the world should look at this and say it's going to happen more to other people in other areas. it just has, well, an effect on marine life and marine animals and the wildlife on land. >> reporter: dr. james wilder studies the polar bear population in the beaufort sea near barter island. he says these bears have been coming to these shores for thousands of years, but climate change has changed their behavior. >> polar bears are showing up earlier. i mean, they used to show up in the beginning of september.

now we see them showing up in the late july, august, and staying for longer, and that seems to be correlated with the availability of sea ice. so if sea ice melts earlier, then bears will come to shore sooner. and if it forms later in the fall, then they aggregate on the coast for longer periods of time. >> it's not good for us. we're used to ice out there hunting the whale. >> reporter: for the people of kaktovik their way of life is at risk as well. >> this is the road i grew up on, the main road. >> reporter: marie rexford is a witness to the changes wrought by rising temperatures. >> good attraction for all the tourists. to us they're a nuisance. they can smell your good food anywhere. they have broken down our door to our cellars. >> reporter: for centuries residents stored the whales they hunted in the permafrost, a natural underground freezer. >> most of the ice cellars filled up with water, and it's hard to keep them going. >> you used to have natural ice cellars. >> yeah, yeah. >> that have now melted? >> they washed out. erosion got all of them. they're all gone. >> and now you've got

containers. >> reporter: relying on the earth for sustenance is something the people of kaktovik need to do because even though there is a grocery store here, that doesn't mean groceries are accessible for everyone. >> $21 for a bottle of lotion. everywhere you look prices are about three times. $34 for conditioner. it's tough. the prices are a lot higher. >> how challenging is it to keep your store stocked here on barter island? >> the planes are fully loaded with tourists and they're not bringing -- we're slowly getting our mail and our groceries. >> it costs so much for you to get everything here. >> yeah. my prices are just crazy sometimes. >> reporter: another concern here is safety. while the locals know what to do about bears -- most people here have firearms just in case? >> we try to scare them off before anything else. visitors won't. >> they don't really understand

>> right. i mean, you all live among them with them. you understand. >> it can get crazy when they start coming in, especially when they finish all the blubber at the bone pile, they'll end up -- start coming into the town looking for scraps. so, yeah. >> they're hungry. >> they're smart animals. >> reporter: bears coming into town proving to be such a problem, there was a polar bear patrol that sweeps the streets. this bear rummaging through garbage. another peering into a window. >> i used to lock up with a bar that went from across. >> reporter: and our hotel's manager shows us how she locks the bears out at the end of her shift. >> and that's why i do it, so bears can't get in here.

>> reporter: but we brave the dark to catch a glimpse of the northern lights. >> so it's around 3:30 in the morning, and i looked out my window, and i saw the northern lights. so i woke everybody up, and we're heading outside now to check them out. >> reporter: then the sounds of dogs barking. a warning that polar bears aren't far off. >> we heard some dogs barking. this is the time of night the polar bears are out. we're going to stay close to this door. it's unbelievable because i've seen pictures. i never thought i'd actually see it in person. and there it is. in the sky. and it's surreal, actually. it's just as beautiful as i thought it would be. >> reporter: when we take off from barter island, we're in awe of what we have seen here. the polar bears and the people. the fierceness and the fragility of this arctic world. a once-in-a-lifetime opportunity that may be melting away. and next, the newest viral star and she's not what you'd expect.

>> announcer: "into the wild," a special presentation of "nightline" continues. here again, juju chang. we're about to meet a social media heavy hitter. pun intended. she's a hippo. her name is fiona. she was born premature and struggling to breathe and gained millions of devoted fans as her caretakers nursed her to health in a series of facebook videos. here's abc's erielle reshef. >> she's the unlikely viral star. >> look at this. >> hey, cutie. >> oh, my goodness. >> splashing her way into the hearts and screens of millions

around the globe. >> she's precious. >> fiona is a diva. >> she is a ham. >> fiona the hippo. from premature baby to bona fide brand given her own ice cream. even "time's" person of the year. fiona joining the ranks of animal celebs, with massive social reach like marnie the dog and nala the cat with 3.5 million followers and when april the giraffe last year gave birth 14 million watched live in one day. hippos are not exactly the cuddliest of animals so how did this one become a celebrity. fiona's journey to stardom began in the womb, the first nile hippo to be born in the cincinnati zoo in 75 years but she almost didn't make it, her mother bibi went into labor sixt

>> we were told the prognosis isn't very good at all. >> her lungs weren't strong enough neither was her overall muscle control. >> and she weighed just 29 pounds. a typical newborn baby hippo weighs between 55 to 120 pounds. >> your ears wiggle. >> she was placed into an ad hoc hippo nicu and put on an iv and put on around the clock care and the keepers and zoo staff fighting to keep the baby hippo alive. >> it was touch and go at the beginning. we didn't know what was in hippo milk. we had to send off to be analyzed. >> small moments becoming big victories as the world watched as she learned to stand. >> i stand. i'm a big girl. >> how to swim. and even took her first steps. >> i became emotionally attached, just like the rest of the world, and a few times i really didn't think she was going to survive. >> but the little one didn't just survive she thrived.

>> so to see her start crossing those kind of lines that we didn't even know she would ever gangbusters, she just blew everybody out of the water. >> as she grew so did her following. >> big girl panties on. >> here's a six-week-old fiona stubbornly learning how to walk up and down a ramp. >> big bump. >> the tiny triumph viewed over 21 million times on facebook. she's more than doubled the zoo's following. what does she typically eat every day. >> we are weening her off the bottle. so she's getting 3,000 milliliters of formula a day and also eating an adult diet with grain, hay and loves produce like lettuce, apples, squash and on special occasions she gets watermelon and pumpkin. those are some of her favorites. >> naturally i to get up close to the social media star and she played perfectly to the camera. strike a pose, little one.

>> a true diva in action. >> what's it like day in and day out to see all the people come from all over the world to see fiona and b. >> it's still amazing, still to this day when you let her out you hear the crowd going crazy. >> fiona is a bright spot for a zoo that recently survived a dark episode, the controversial killing of a silver back gorilla after a child plunged into the enclosure. >> a 3-year-old child has fallen into the gorilla cage. >> the scene, ten minutes of horror. the boy's mother watching helplessly from above. >> oh, my god. oh, my god. >> then a critical calculation by zoo officials to shoot the 450-pound animal to save the child's life. this is the zoo's director. last year was a tough year with

the killing of harambe. how has this changed the zoo? >> last year was a challenging time particularly for the people who worked with harambe because animal care givers, zookeepers work with their animals and it's like we two with our pets and also like our kids, i mean, they love their animals so that was a hard time. >> but in 2017 baby fiona changed the mood at the zoo. record attendance followed up by 20% from the previous year. zoo officials nicknaming the fiona effect. what is the fiona effect? >> she has really represented hope and being saved prosecutor the brink. people love that animal. >> fiona's underdog story providing rare common ground in a divisive year. >> who can't get behind a sweet baby hippo. >> her spirit of resilience resonating with the visitors who

come to see her swim and play. >> when she was premature i was diagnosed with breast cancer. so me and her kind of fought a battle together. >> i've had losses of children before and so when fiona made it through i was really excited. >> little kids would write handwritten letters, fiona, i was a preemie too and i'm okay now and here's a picture of me on my soccer team and you can >> oh, my gosh. so cute. >> dainty. >> her short life story now even being told in books. >> i have tried to see her many more times. i got to come to the media preview and saw her for the first time and completely lost my mind and completely lost all journalistic integrity and freaked out in front of the window.

>> fiona loves to play it up for the crowds. and mom always joins in. here she is. hi. look at this. >> today fiona is happy, healthy and hefty, weighing nearly 800 pounds. in january she celebrated her first birthday. ♪ happy birthday to you ♪ happy birthday dear fiona >> she's got a bright future ahead. she'll have lots of fans, lots of lettuce maybe years down the road a young man in her future. we'll have to vet him strongly. up next saving the exotic pink dolphins of south america. >> announcer: "into the wild," up next saving the exotic pink dolphins of south america. south america. 's gotten used toe room smelling like sweaty odors. yup, he's gone noseblind. he thinks it smells fine, but his mom smells this... luckily for all your hard-to-wash fabrics... ...there's febreze fabric refresher. febreze doesn't just mask, it eliminates odors you've... ...gone noseblind to. and try febreze unstopables for fabric.

with up to twice the fresh scent power, you'll want to try it... ...again and again and maybe just one more time. indulge in irresistible freshness. febreze unstopables. breathe happy.

no matter how much you clean, does your house still smell stuffy? that's because your home is filled with soft surfaces that trap odors and release them back into the room. so, try febreze fabric refresher. febreze finds odors trapped in fabrics and cleans them away as it dries. use febreze every time you tidy up to keep your whole house smelling fresh air clean. fabric refresher even works for clothes you want to wear another day. make febreze part of your clean routine for whole home freshness.

>> announcer: "into the wild," >> announcer: "into the wild," a special presentation of "nightline" continues. once again, juju chang. we jump now now to the amazon river to track down a species as elusive as it is exotic. pink dolphins are legendary in this part of the world but rarely seen in person. here's abc's victor oquendo.

playful. but there's one rare subspecies that remains a mystery to scientists. the pink dolphin of the amazon river is a living legend. and at the end of 2017, we caught our first glimpse. >> right now they've got one dolphin. you can see it right there behind me. it's totally surrounded. the world wildlife fund is on a mission to tag 15 dolphins throughout brazil, colombia, and here in bolivia, to study their health and behavior. the group consists of local fishermen and scientists. scientists fear the pink river dolphin is vulnerable to extinction due mostly to manmade threats like mining, hunting, and deforestat

waiting for them under tents is a makeshift o.r. >> they're bringing the dolphin out of the boat. very quick process, they move fast. pink dolphins can only be out of the water for just under 60 minutes. with the clock ticking, veterinarian karla sanchez and her team hydrate the dolphin to lower its stress. >> she's checking the temperature. they will work in a sequence. they will start with checking t will do measurements on the dolphin. >> reporter: as they conduct a physical, the researchers numb its tail then take tissue and

blood samples to test for mercury, toxic substances, and general health. selfie don't know for sure how these freshwater dolphins get their pink color. hypotheses include diet, water quality, and sunlight exposure. but they do know they get pinker as they age. a pink dolphin, why aren't they more well known? >> i think we didn't communicate about these dolphins. they are very attractive, they are more cute, in my opinion, than the marine dolphins. >> reporter: as quickly as it came out, the dolphin is returned to the water. pink dolphins are known as an indicator species highlighting the overall health of the amazon. if they're doing well, so is the river. but deforestation has been changing the water. >> all the deforestation is having an impact, because the less trees, that means there's more runoff. and more runoff means there's more sediment getting into the rivers. >> reporter: and that sediment swimming freely, as it did in 2010 when these trapped dolphins had to be rescued. eight years later deforestation

is an ongoing concern. it's just after 4:00 a.m. we all just got up. we're about to drive two hours into camp and then head right out into the amazon. with one more dolphin to tag, we embark on a nearly three-hour journey through punishing terrain. >> you have to be really careful on these roads. the road is more just mud and water. for those who get trapped, that mud can seem like quicksand. bolivian ingenuity at its finest. leading the tracking charge is paul van dam, biologist and director of a bolivian ngo, bon agua. >> we want to know how far they travel in the river, searching for females, searching for family, searching for food. so, this is what we actually want to investigate. >> reporter: and just minutes after boarding our canoes, a downpour. >> we are setting out in the rain. so we're a bit unlucky. but rain does not interfere in the capture of the dolphin. >> reporter: the ride out is bumpy. after an hour, the fishermen find a lookout point for the elusive dolphin. >> we're now setting up our camp.

so the fishermen are preparing the setup to put the next -- to capture the dolphins. >> reporter: while some work frantically through the cold rain, others take refuge in the much warmer amazon river. when the rain finally settles, it's go time. [ speaking a foreign language ] the team starts by checking its vitals. right now they have to work as quickly as possible, and they also want to make sure to keep it very calm. that's why i'm talking very slowly right now. with the examination complete, the tagging begins. each tag will ping data back to a satellite once a day. this drill, commonly found in your toolbox, becomes vital to tracking these mammals. >> first thing they had to do was disinfect the whole area. then give it an anesthetic. and one guy right here, all he's

doing is holding the snout shut. because the dorsal fin is made of collagen, the dolphin's pain will be minimal. >> we're actually inserting it right now. it's like a mixture of rubber and metal. [ speaking a foreign language ] >> reporter: and within moments the tracker is attached. now there's a rush to get it right back into the water. and she's set free. for people in the united states, what do you hope that they learn? >> it's important that they have to be aware that this type of conservation of this species is something global. it's not something local. i think we need support from the global community to conserve this species. >> reporter: now they wait in hopes this data will shed light on how to protect this mysterious and beautiful animal.

up next it's just like a petting zoo except the animals pet you. inside nairobi's giraffe manor. insi inside nye roby's giraffe manor.

>> announcer: "into the wild," a special presentation of "nightline" continues. you know, just seeing a giraffe up close is

unforgettable experience. but being licked in the face by one is surreal. trust me. at giraffe manor in nairobi, kenya, you can live out your giraffe dreams and get neck to neck with them. it's breakfast time at giraffe manner and this morning, my table for one has lean and lanky party crashers. excuse me. we have to have a little decorum here. one for you. one for me. fraternizing with the guests is not only allowed but encouraged here so that visitors feel a kinship with these great but increasingly vulnerable animals. i usually don't kiss on the first date. their tongue feels a little sandpapery. i'm sure she has criticisms of me too. what are you doing for breakfast tomorrow? >> it's all standard fare at this most extraordinary of hotels outside of nairobi, kenya where we traveled last year.

built in the 1903s in the style of a scottish hunting lodge now owned by fourth generation kenyans. everywhere you turn, there they are. >> they love interaction. >> they have characters. >> interrupting our interview. just got nudged. >> currently there are 12 giraffes here. we have margaret, selma, right at the end is kelly. kelly is -- you can see she is slightly pregnant. the stomach is slightly distended. >> but it's not all tea and crumpets for these genteel giants. giraffes are facing what experts call a silent extinction. population down 40% in 20 years. inexplicably they were only called vulnerable for the first time in 2016. >> some of the species are down

60% of the numbers. and by 2030, the trend continues and the species will be extinct. >> reporter: to put that in perspective, there are far more elephants whose plight is much more well known than giraffes, 500,000 versus just 90,000. which is news to some of their guests. >> i didn't realize that until we came here. >> you cannot imagine that the gentle animal can be threatened. but the history of this place is built simply on this that threat. >> indeed giraffe manor was created on the premise of saving these elegant creatures. back in the '70s, the then owner, an american, former fashion model convinced her husband to allow three giraffes to live on their land when their habitat was in danger. >> she managed to persuade her husband this is a great thing to do. they wanted to save this amazing species of giraffe and grow them from -- to nairobi, to

repopulate them again. in the wild again. >> part of the hotel's land is dedicated to the giraffe center which educates the local population and fosters breeding programs to increase giraffes in the wild. a percentage of every room fee in the manor goes to the center. when we come back, we head to nairobi national park to see the threats up close. >> if you look up ahead, you can see the problem. >> and meet one person on a crusade to save these beautiful creatures before it's too late. these beautiful creatures before it's too late. he these beautiful creatures before it's too late. e these beautiful creatures before it's too late. these beautiful creatures before it's too late. ...gone noseblind to. and try febreze unstopables for fabric. with up to twice the fresh scent power, you'll want to try it... ...again and again and maybe just one more time.

indulge in irresistible freshness. febreze unstopables. breathe happy. anif you've got a lifee. you gotta swiffer

no matter how much you clean, does your house still smell stuffy? that's because your home is filled with soft surfaces that trap odors and release them back into the room. so, try febreze fabric refresher. febreze finds odors trapped in fabrics and cleans them away as it dries. use febreze every time you tidy up to keep your whole house smelling fresh air clean. fabric refresher even works for clothes you want to wear another day. make febreze part of your clean routine for whole home freshness.

>> announcer: "into the wild," a special presentation of "nightline" continues. juju chang reports. >> reporter: giraffes, nature's gentle giants, are facing what experts call a silent extinction. their population down 40% in 20 years. one of the biggest issues facing giraffes is urban encroachment. as populations grow and cities expand, their lose their habitats. to get a sense of how closely the urban sprawl is approaching

on the habitat, this is the national park, and this is the highway. nowhere is it more clear than nairobi national park. just miles away from giraffe manor, at 44 square miles, it's twice the size of manhattan, yet its parameters are whittled down. >> that is downtown nairobi. >> reporter: we head into the park with the giraffe conservation foundation. he is getting his ph.d. at michigan state. traffic jam. amidst the monkeys, zebras and giraffes dotting the landscape, another ubiquitous sight. this sums it up, that man is encoaching on his habitat. >> yes. if you look straight up ahead, you can see the real problem. so those are housing developments coming up. >> yeah. >> and a few years back, we never had that. and all this used to be open,

animals could migrate going that way but now most of those areas are just inaccessible. >> reporter: detour. that giraffe is completely holding its ground. it's like, huh-uh, i ain't moving. you're in my 'hood. a giraffe's kick could break a lion's back. but they are killed off from trophy hunters to poachers. >> they are hunted for their meat, skull and bones. in some places it's traditional medicine and believe that bones and bone marry can cure aids. in some places they're hunted for their tails only. >> reporter: so they will kill an animal -- >> for the small tail. >> reporter: man is the biggest threat to giraffe, i guess. >> yeah, in a nutshell. that's one way to put it. >> reporter: arthur's foundation has gone to dramatic lengths to reverse these trends, tracking poaching snares and in one ambitious project transporting giraffes across the nile river by ferry, away from the devastating oil drilling in uganda as seen in this pbs

documentary, "africa's gentle giants." >> we've just crossed over the nile river with six giraffe. i have never been so stressed in my life. >> reporter: adding to this, a pr opportunity for the glorious animals. >> the thing is we have had good media coverage. so giraffe, this has really just come up in the last ten years. >> right. >> so there's a real need to do more and get more data and see what you can do better to protect the population. >> reporter: you think they have silently been going extinct? >> they are heading in that direction. >> reporter: a grim reality as nothing is more dangerous to these beautiful creatures than silence. our thanks to you for helping us breathe silence. we're so glad you could join us for this special presentation of "nightline." catch us every weeknight after "jimmy kimmel live" right here on abc or online on our on abc or online on our "nightline" facebook page.

man: the kettle corn, caramel corn, large, small? i'm gonna do a large kettle corn. large kettle. fresh made. perfect. all right. excuse me, coming through. pardon me, excuse me, coming through. pardon me, excuse me, all right, all right. how's everybody doing? we have arrived. ladies and gentlemen, welcome to the "road to x games," boise park qualifier. we've got bmx, we've got skateboard, men's and women's qualifier, harley-davidson hooligan racing. we've got the best seat in the house in the most beautiful place on the planet, hence the nickname the gem state, downtown boise, idaho. this is it. the final show, last chance to qualify for the big show, x games minneapolis. are you guys ready or what? [ cheers and applause ] let's do this! let's start the show! my goodness! there goes my kettle corn. kettle corn, please!