Ah, mountain gorillas have been on the brink of extinction. But are the only primates currently increasing in number . Reaching the milestone, 1000 gorillas has been remarkable. So its extremely good news. But while the mountain gorilla population increases, what happens when their habitat does not grow with them . Yeah, because that thought, there are far more cases of guerrilla groups attacking each other than there used to be with fatalities on a regular basis. Yes. Your last days, this is something from one into group faith. And that is, i think one thing we want to know whether the stress levels are increasing. If we dont like to know, we at risk of not being able to do which in turn years, for example, from now, conservationists and scientists face a growing number of challenges and questions. Whats our goal . 801502000 guerrillas. Is it still a wild population, or when does it become a wild . Do . Lou, the ruthless surviving mountain gorillas live in 2 relatively small areas in the east of africa. One population lives on the slopes of the veranda mountains. A chain of volcanoes straddling the border region between ver wanda, uganda and the democratic republic of congo. The other is located just 30 kilometers to the north in uganda. Ringback in the windy, impenetrable forest, a primeval lowland and mountain rain, forest region. 331 square kilometers of land known for its exceptional biodiversity, or home to over 400. 00 of the worlds Last Mountain gorillas. The kind of terrain that makes it difficult to determine their exact numbers. There is also a reason is called impenetrable. Now the vegetation is very done. You could have a grill and not very far away from here and not know it because of all of it. Martha robins from the Max Planck Institute in germany is on her way to the mo cheese a group of guerrillas. Each plan is assigned the same name as back into its liter, a silver back. Ah after a 90 minute hike, the american anthropologist reaches her destination. We where surgical masks when were with them, the guerrillas, if were within 10 meters of them, we wear them. Because even though right now i feel very healthy. Im not exhibiting any signs of having a cold. I may still be carrying it. And the last thing i want to do is get these gorilla thick. So theres several, right . Yeah. If we just wait, theyre going across right across here. This is very rare. That adult female was ms. Jenny, she has the youngest baby who was about 9 months old now. But interestingly, she was also carrying a 2nd infant which was not hers. A 2nd infant get the fairfax got comcast. There are 13 gorillas in this group. The silverback is about 20 years old. He has been habituated from birth, ive actually watched him grow up, which is pretty cool. Habitually it means that the silver back and his group have been introduced to the presence of humans. The Behavioral Scientist observes what the animals eat, how they interact, and how the individuals differ. Studying every detail of their worlds. Although always from a distance where these habituated guerrillas, its amazing because they kind of led us into their world. So we can observe their day to day activities. Its always very thrilling to see their new babies and to see them grow this ones at the breach the age where hes starting to explore everything and its, its really quite fun to watch. And the broader view, though, its very exciting and good to know that every new baby represents a healthy population and represents that the population is growing. The mountain guerrillas are the only great apes in the world known to be increasing in population. At the end of 2018, the International Union for conservation of nature announced the highly encouraging news that they were now classified as merely endangered. In contrast to other gorilla species, which remained critically endangered Martha Robins has witnessed that recovery in the course of her research. He was born in 1999 and i go out there now and i see him leading a group with 5 adult females. Hes got his own kids climbing all over him. I feel so privilege that ive been able to watch the same gorilla over 20 years. Every 5 years, the researchers conduct a precise census of the gorilla. Its often an exercise in extreme patience. Not all of the groups of wendy guerrillas are easy to track constantly to ensure that every single animal is counted. The team painstakingly comes every section of the rain forest in the process covering several 1000 kilometers on foot. During the fences, we have 6 teams of 5 people working over a period of about 3 months. I have been involved in 5, not in girl offensive, and it is by far the most difficult work i have done here from east twist. So for example, this map, if with one that is since us, so for example, to, to move, i dont want you said, then to move in, then you drop. I was, i need, if i was part over there over there. But the main thing were looking for is fresh gorilla trail. So when the girls walk through the forest, theyre eating face, theyre big animals. So they passed down vegetation, which there was a lot of here. And the trackers experience people were able to see. This is a gorilla trail, and if we find that its great, because then we will track to the sites and be able to count enough and collect guerrillas make now every night. So the spend down vegetation and sit in it. And if you have 10 guerrillas in a group, maybe youll find 8 now, and maybe 2 of those nes, have big adult size theses in it, and then small baby size species. And so thats how we can ascertain that there are probably 10 guerrillas in that group, but to ensure that, that numbers accurate. And its not a case where one gorilla made a nef and actually didnt like who they were sleeping next to. So they made it someplace out, and we double count that gorilla. We also do genetic analysis with the thesis. We know that this is an endangered population. And the way i look at it is imagine youre a business man. And imagine you make tooth paste. So again, something very basic, you would want to track how much to space youre making, how much youre selling, and what to do if youre not selling any. So its kind of the same with conserving endangered species where we need to know how many there are and whether its increasing or decreasing. Because that gives us some indication as to whether the Conservation Strategies are working or not. Or whether we should try something different. Ah, just 30 kilometers south in the veronica region. Those Conservation Strategies have already proved fruitful on the horizon, the chain of volcanoes scaling over 3000 meters high that give the park its name. The mountain gorilla population here has doubled over the last 3 decades. The most recent census covering the border region between uganda, the democratic republic of congo, and were wanda counted 600 for animals. The Rwandan Government has banned poaching and logging in the National Park and introduced a controlled tourism concept. Part of the resulting revenue is assigned to nature conservation, while 10 percent goes towards the construction of schools, roads and hospitals. And the region. Masonic is the gateway to the National Park. A city of around 100000, that his florist with the resurgence and tourism. A promising example of her wandas Rapid Development since the genocide of 1994. I am with fair german gorilla expert vinny eckart is a long term associate of the care. So he research center, shes continuing the work of diane farsi who set up the facility after coming to her wanda, in 1967 dash i to stand in house on this desk was in diane facies house and had been secured before the conflict in rwanda began she would sit here practically every evening at her desk with her typewriter and record, or the details shed observed in the groups shed visited during the day that couldnt observe ations that enabled the pioneering american researcher to start compiling a unique collection of data thought on august this finance nom, fungal, but its del, exciting to find names of guerrillas that weve been monitoring since they were really young and watching them grow out of his habit. Its really impressive. How detailed how observations. Well, its elephant about that hut. In the 19 seventys diane fuzzy counted a solitary to 154 mountain gorillas, prompting her to embark on an uncompromising fight against poachers and the deforestation of the mountain reenforced. At the same time, however, that commitment was not always welcome and earned her many enemies entitled to us at the time when diana fussy was still alive and protecting the guerrillas. She didnt believe that they would survive until the year 2000. She assumed that guerrillas would be extinct by then. Yup. At almost wisconsin, diane fuzzy did not live to see the turn around me animals for chance. She was murdered in her cabin in 1985 of her wanton court found her Research Assistant guilty and absentia. But some experts suggested the true culprit was a poacher, but her efforts helped the world to learn about the fate of the great apes. Conservation measures started producing results. The mountain gorillas numbers finally began to rise again, albeit with unforeseen consequences. But the use in that is a dell name. What we see here is that habitat the be so kindly, simple the kerosene b volcano. And this is approximately where diane foresee set up her 10 said of cobalt when vinny, a car to begin her research and rwanda in 2004, there were 3 groups of guerrillas. Each shifting trail scene here represents their respective movement patterns. These appointments and we behind the site, weve seen a tremendous growth in these groups over a period of 15 years as many as 65 guerrillas in the pablo group, which is an absolute world record, the math. And so the in 2004, i wasnt aware that it could be more than one silver back in a group. What happened in 2007 took us all by surprise, slashed on a protracted period of stability, was followed by chaos. Lung cancer forced end from the thick of 1165 gorillas in one group couldnt work well for long. Again, we were waiting for something to happen in the groups, partly split up males dotted to form their own group with some female. It is called acquitted of pablo, for example, split into several groups. And instead of 3 groups before we had at times, 12 groups. So with 3 times as many groups in the same area, hi, martha has less habitat. The i grew up a paul and with groups encountering each other. More often, interactions can be incredibly stressful. Twice as the males camina fight to the death and things can also get critical for the young animals is al, from spirit thought vinnie a car tender a team of researchers visit the National Park several times a week. Their mission is to find out how the guerrillas are reacting to their increasingly crowded habitat. The veronica is a small protected area surrounded by a region that is extensively farm by local residents, with their fields reaching right up to the borders of the park. And the primates cannot simply migrate when conditions become constraint. Vinny eckart wants to explore the social dynamics between the primates. Shes now on her way to a group named after a former dominant silverback pablo. After living through major upheavals in the past. The group currently number is 24 animals at the border of the National Park, the scientists meet some park rangers. They usually know exactly where the individual groups are at any given time. The Team Announced their arrival in the guerrillas own language. Lucian. Okay. Yes, i know its dance cold belch well, we use it when we arrive and kathy approached the group, but it looks like a greeting. We hey, now way coming. Its all good on his food. Is actually open. You can see the size of the vegetation, vegetable cause of the belch vowels are very important. So they can hara fields often with him. Okay. Those are very special friend. Unfortunately, a bit too curious. Sometimes a flight cook that maybe just take the camera down for a bit when the mom was in the day the pablo group are in a peaceful mood. 3 gorilla babies enjoy frolicking around in the morning. Sun completely depend completely dependent on their mothers their breast fed until theyre about 3 and a half years old. At 9 months, they start nibbling on their 1st plants. And step by step, learn to stand on their own feet in the jungle classroom. Ah. But only if an incline im where you can see the little one thats zulu younger than any other he loves to planes much while sometimes he plays alone. Like right now. I thought she was probably unable to find a playmate, but it wont be long until another youngster comes around, which is a welcome invitation. We will collide, madam. Ah, ah at this age fights between the young apes are all about playing. But if the juvenile male wants to challenge the dominant, silver back orphan outside, gorilla tries to win the affections of females from the group. Things can suddenly take a very aggressive turn. The growing population density over recent years has seen such fights become increasingly frequent. Oh the im fly tullison in 2007 we had about one interaction per month yet. So now we sometimes see up to 3 a day between different groups. So the interaction rate has become extremely high. Name woke a gun, babies faced the greatest danger during such fights. As long as the guerrilla mother is still nursing, shes not ready to meet again. When a male manages to learn a way a female, hell almost always kill her young so that he can sire his own offspring with her sooner. Infanticide is a phenomenon seen in a range of animals when unless life alert said i know of course its one of those things that are very hard to be witness to and to process you want to intervene life a little but you know that its natural behavior that you have to exam and you have to toughen up and not let things get to, you know, unless, but of course its really difficult can be youve known the young ones and they mothers from day one. And you can see them really suffering and distress. Its exert from the whole group. Its hard to accept it. Thats how it is for a while. So thats not the researchers. Observations have produced some surprising scientific results, whether planning, 15000 kilometers away. Tommy or cargo is a professor of anthropology at the university of california. Davis, where diane farsi once studied for 2 semesters, the french gorilla researcher updates his students on the latest developments. Depressed, very depressed. Yes. So they do. Yeah. They get that. They have, you know, corridors are like most mammals actually they have feelings. A female girl who loses her all spray will be sat for a period of time, but eventually shed get over 8th us. She would get pregnant again and hopefully forget a little bit about the tragedy of hover. But i do remember distinctly observe a female girl, and i remember that i was just lost all spring and she looked sad and she was always sort of on the edge of the group. Not very active, not play food for a few months after the death of rosman. No dummy o. K o is focus is on long term data. He uses quantitative methods to monitor patterns and developments covering years or decades and visits the guerrillas in the wild on a regular basis. He benefits from the long term records compiled by the field researchers in rwanda. Half a century of observations initiated by diane fussy, have resulted in a massive database that now enables new insights. Who was the come on cur, early them because you can clearly see that there were almost no cases of infanticide in rwanda between 1982000. After that, the number of cases increased dramatically as shown by these little red asterisks here over the last 10 years for the mortality rate of baby gorillas due to infanticide has increased by fold. Plus the mortality rate among male gorillas has also risen as a result of wounds they incurred during those encounters. You can use analyses provide the basis for forecasts about the guerrillas future. Does the Enormous Growth in population pose a threat to the animals Healthy Development . Non jablonsky of pure natural ad walden f with were seeing a level of violence that is no longer naturally us. Thats causing a slow down in population growth. And if that level of aggression persistence, it might even start shrinking. Latoya mamma, the quad home dice yos and leave with i guess with continuous cycle teaberry got mode lather and in addition to the population, no longer self adjusting stress levels are also on the up. Its a problem we really need to resolve back in her wander, katos fellow researcher, vinny i caught, is trying to track down the source of at the same stress problem was here. This is our 1st concern was finding out how stressful these interactions can be within a group to come on that sometimes extremely peaceful, especially with groups that would have only recently separated. And it will sometimes be just a playful encounter. But it can also get very, very aggressive efficacy if applauding from direct observation alone, the scientists cannot gauge the physiological impact that stress can have on individual guerrillas. Which is why vinnie a cart is likewise interested in the animals feces. Yasmina would papa fun and wipes this is a fico sample from a female that just passed by that in you dont need that much. I used the glove as a conveyor. Im just turn it inside out. Pretty straightforward. The foster on and then tie not. And when i next do you need to write down what time it is of noon . Ill try it. If its is as well and sunfish, its 1121. 00. I am ritual, the fecal sample is from move capture. Do that. So code to lloyd. And so the town people in the lab know who sample it is with us. I felt the note up really small klein and push it into the glove. He opened. I gushed bmw with this info. I would say to lee more do it, but not easy to learn more. Hold your book, but to try our best. Another fancy before we affectionately call this app. Hoop, lab of a 4th or not revs and martin are doing right now is extracting hormones from the fecal samples we collected in the forest by the summer time. As is the case with humans to stress trigger is a hormonal Chain Reaction and gorillas bodies. When i integral our inches from the o exposure to a stress factor and leads to a very long stress cascade the fun. These are the end products from that reaction of n, incorporated into the feces via the intestines, and then excrete it on done with kashi. And that gives us an opportunity to determine the stress level without needing to take a blood sample. If my husband can, because trust is and his advice, beautiful. And heres an example of a very aggressive interaction that took the group completely by surprise. As i said, a silver back a