Australasian Western Lowland Gorilla Population

And back in 1997, Melbourne was able to group all of those gorillas together (besides Rigo). Bambuti (1994) was also mostly mother raised by Betsy; I believe the keepers only assisted on some occasions. It was surprising that Betsy had learnt so quickly with Buzandi and was able to implement the skills she learnt to Bambuti.

Motoba also lived successfully with Buluman, which was something that was very intriguing to me. Apparently they shared the role of silverback; Buluman had no problem with Motoba mating with his females ect. This may have been a result of his upbringing, never fully being part of a normal social group.

Melbourne taking on Julia and G Ann would’ve probably been their only option when looking for females from overseas at the time. It would’ve been much better if they were grouped with Rigo to form a second troop, and then they could’ve imported some females to live in Motoba’s troop where at least Betsy and Yuska were somewhat normal; Betsy could mother raise infants, and Yuska seemed a normal gorilla. I read somewhere that keepers actually believed Yuska knew how to raise a baby gorilla but let the keepers do all the hard work over the first few years, before she took the baby back once it was old enough to sort of not require full attention from her.

The interesting thing about Buluman, Betsy, Rigo and Yuska is that although they were taken from their natal troops as infants, they were raised in pairs. This obviously wasn’t as favourable as being peer raised with multiple infants, but clearly gave them (the females especially) some advantages and their social state was consequently in between that of a mother raised gorilla and a hand raised gorilla.

Compare them to Mouila at Taronga Zoo, who was captured from the wild at the age of two. She was peer raised along with several infants (seven from memory) at Apheneul and was consequently a socially normally gorilla.
 
The interesting thing about Buluman, Betsy, Rigo and Yuska is that although they were taken from their natal troops as infants, they were raised in pairs. This obviously wasn’t as favourable as being peer raised with multiple infants, but clearly gave them (the females especially) some advantages and their social state was consequently in between that of a mother raised gorilla and a hand raised gorilla.

Compare them to Mouila at Taronga Zoo, who was captured from the wild at the age of two. She was peer raised along with several infants (seven from memory) at Apheneul and was consequently a socially normally gorilla.

I think Motaba was able to live successfully with Buluman as he(Buluman) wasn't a completely normal male- did he have low testosterone levels perhaps? I heard he contracted mumps at one stage, if true that could have affected him. I remember when I saw him he lacked some male characteristics; the dense silver saddle, or very thick arm hair of a typical silverback and was quiet and relaxed. I've seen other 'quiet' males rather like him in Europe too. Joe at Twycross( wildcaught as baby) and Assumbo (born Jersey, now at Rostock) are two examples. More recently Assumbo- another non-breeder, who they think has low testosterone levels, easily accepted an unrelated young male into his group,(aged 5 at the introduction) and like the Buluman/Motaba situation, as he grew the young mother-raised male soon fathered young with two females.

On the other hand Rigo was a typical fiesty silverback in his youth. I believed that A I was necessary as he didn't mate Yuska due to the 'platonic' relationship developed from growing up together. So I was surprised to see a much more recent photo of them mating as much older adults when Rigo had the group.

Apenheul's Mouila was the first female there to have a baby. I remember they gave her a young spider monkey to handle (under keeper supervision) while she was pregnant, to help her practise natal care. In the event( or because of it?) she looked after her first baby perfectly anyway.
 
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I think Motaba was able to live successfully with Buluman as he(Buluman) wasn't a completely normal male- did he have low testosterone levels perhaps? I heard he contracted mumps at one stage, if true that could have affected him. I remember when I saw him he lacked some male characteristics; the dense silver saddle, or very thick arm hair of a typical silverback and was quiet and relaxed. I've seen other 'quiet' males rather like him in Europe too. Joe at Twycross( wildcaught as baby) and Assumbo (born Jersey, now at Rostock) are two examples. More recently Assumbo- another non-breeder, who they think has low testosterone levels, easily accepted an unrelated young male into his group,(aged 5 at the introduction) and like the Buluman/Motaba situation, as he grew the young mother-raised male soon fathered young with two females.

On the other hand Rigo was a typical fiesty silverback in his youth. I believed that A I was necessary as he didn't mate Yuska due to the 'platonic' relationship developed from growing up together. So I was surprised to see a much more recent photo of them mating as much older adults when Rigo had the group.

Apenheul's Mouila was the first female there to have a baby. I remember they gave her a young spider monkey to handle (under keeper supervision) while she was pregnant, to help her practise natal care. In the event( or because of it?) she looked after her first baby perfectly anyway.

Buluman was sterile (presumably due to the mumps), but I’m not aware of him having low testosterone levels - it’s a possibility though and would explain his tolerance of Motoba mating the females. I’d previously assumed it was more a consequence of him being a behavioural non breeder. It was after all, atypical behaviour of a silverback who would normally be enraged by seeing another male mate with his females.

I believe the indifference of Rigo and Yuska came as much from Yuska, given she initially assumed dominance of the troop - a role that was only reversed by the introduction of the adolescent female Mbeli in 2010. Realising Mbeli would quickly outshine her, she began mating with Rigo too. My interpretation was that Yuska understood precisely her role as a female (as she’s demonstrated with other silverbacks); but knew she could get away with it around Rigo.

That’s interesting to know re. Mouila. Whatever the cause, she was the most patient and doting mother of Taronga’s troop. Kriba was equally as attentive, but short tempered (as is Mbeli); while Frala has always fostered a strong sense of independence in her offspring. I’ve seen videos of her brushing her sons from Kibabu’s troop aside when she preoccupied. Nonetheless, she’s been very successful in raising infants over the years.
 
I think Motaba was able to live successfully with Buluman as he(Buluman) wasn't a completely normal male- did he have low testosterone levels perhaps? I heard he contracted mumps at one stage, if true that could have affected him. I remember when I saw him he lacked some male characteristics; the dense silver saddle, or very thick arm hair of a typical silverback and was quiet and relaxed. I've seen other 'quiet' males rather like him in Europe too. Joe at Twycross( wildcaught as baby) and Assumbo (born Jersey, now at Rostock) are two examples. More recently Assumbo- another non-breeder, who they think has low testosterone levels, easily accepted an unrelated young male into his group,(aged 5 at the introduction) and like the Buluman/Motaba situation, as he grew the young mother-raised male soon fathered young with two females.

On the other hand Rigo was a typical fiesty silverback in his youth. I believed that A I was necessary as he didn't mate Yuska due to the 'platonic' relationship developed from growing up together. So I was surprised to see a much more recent photo of them mating as much older adults when Rigo had the group.

Apenheul's Mouila was the first female there to have a baby. I remember they gave her a young spider monkey to handle (under keeper supervision) while she was pregnant, to help her practise natal care. In the event( or because of it?) she looked after her first baby perfectly anyway.

I never saw Buluman personally, but from photos he appears the normal silverback. He was infertile, which was why he never bred, and this may have contributed to the fact that he allowed Motoba to come in and share the role of silverback with him. There was an instance that I read about alone detailing Motoba mating with Betsy right under Bulumans nose! Although Buluman was a very reserved and well natured male. Unnaturally for a silverback he also cared for Betsy’s children, Buzandi and Bambuti. Apparently Betsy allowed Buluman involvement with raising them, and although Buluman wouldn’t play around with them actively, he would still hold them gently and allow them to climb on him ect.

Apparently Yuska and Rigo had grown up together and had formed a somewhat platonic relationship. I do remember reading somewhere about Rigo’s aggression at the time of Mzuri’s birth. Yuska was always gentle natured and loved to get away with whatever she could, such as allowing her keepers to raise her offspring until they were old enough to not be fully reliant on her. She, and the other girls, were very much in charge when Rigo was silverback. Even Motoba allowed the girls to fulfil a similar role. I think that’s why when Otana arrived, the girls were not used to having a dominant male in charge.
 
Buluman was sterile (presumably due to the mumps), but I’m not aware of him having low testosterone levels - it’s a possibility though and would explain his tolerance of Motoba mating the females. I’d previously assumed it was more a consequence of him being a behavioural non breeder. It was after all, atypical behaviour of a silverback who would normally be enraged by seeing another male mate with his females.

I believe the indifference of Rigo and Yuska came as much from Yuska, given she initially assumed dominance of the troop - a role that was only reversed by the introduction of the adolescent female Mbeli in 2010. Realising Mbeli would quickly outshine her, she began mating with Rigo too. My interpretation was that Yuska understood precisely her role as a female (as she’s demonstrated with other silverbacks); but knew she could get away with it around Rigo.

That’s interesting to know re. Mouila. Whatever the cause, she was the most patient and doting mother of Taronga’s troop. Kriba was equally as attentive, but short tempered (as is Mbeli); while Frala has always fostered a strong sense of independence in her offspring. I’ve seen videos of her brushing her sons from Kibabu’s troop aside when she preoccupied. Nonetheless, she’s been very successful in raising infants over the years.

Assumbo in Rostock is a similar situation to Buluman's in the past. Not only did he tolerate the arrival of the young mother-raised male, but I think he still plays with him(!) as a nine-year old blackback who fathered the children in 'his' group. Few silverbacks would tolerate mating in front of them or be on such friendly terms with an unrelated made. They have said Assumbo has 'low testosterone levels.

Interesting abou Rigo/Yuska. If he mated okay why did he never father more offspring apart from Ya Kwanza ?

We can't know if the 'spider monkey tuition' helped Mouila be an excellent first time mother or not. As I've said before, I've known other females(even handraised ones) that have never even seen a baby before, become perfect first-time mothers. Romina in Bristol UK and Juju in Howletts UK were both good examples.
 
Interesting abou Rigo/Yuska. If he mated okay why did he never father more offspring apart from Ya Kwanza ?

We can't know if the 'spider monkey tuition' helped Mouila be an excellent first time mother or not. As I've said before, I've known other females(even handraised ones) that have never even seen a baby before, become perfect first-time mothers. Romina in Bristol UK and Juju in Howletts UK were both good examples.

In Yuska’s case she was put on contraception permanently following the birth (via caesarean) of Yakini in 1999. Her uterus had thin walls which could have caused placental detachment issues. As for why Mbeli didn’t conceive. I’d assume she had been placed on contraception while still in the Kibabu troop and this was probably still wearing off.

I’m similarly hoping Kipenzi will be an excellent first time mother despite never witnessing a younger sibling being raised. She’s otherwise had a normal upbringing and it’s clear her 43 year old mother is never going to conceive at Mogo. They should switch to Kipenzi and give her a chance. At 11 years old, it’s too late for her to learn through observation if they want to follow that theory.
 
I never saw Buluman personally, but from photos he appears the normal silverback. He was infertile, which was why he never bred, and this may have contributed to the fact that he allowed Motoba to come in and share the role of silverback with him. There was an instance that I read about alone detailing Motoba mating with Betsy right under Bulumans nose! .

The question remains why Buluman was infertile. Was it related to catching mumps and /or low testosterone levels possibly. A male doesn't know he's infertile, so a normally active group leader will not allow another male to mate any his females even if he can't/doesn't father any young himself.
 
In Yuska’s case she was put on contraception permanently following the birth (via caesarean) of Yakini in 1999. Her uterus had thin walls which could have caused placental detachment issues. As for why Mbeli didn’t conceive. I’d assume she had been placed on contraception while still in the Kibabu troop and this was probably still wearing off.

I’m similarly hoping Kipenzi will be an excellent first time mother despite never witnessing a younger sibling being raised. She’s otherwise had a normal upbringing and it’s clear her 43 year old mother is never going to conceive at Mogo. They should switch to Kipenzi and give her a chance. At 11 years old, it’s too late for her to learn through observation if they want to follow that theory.

At least Rigo's grandson Mapeema in Duisburg has furthered Rigo's genes in the population- he has a decent number of offspring.

I would fully expect Kipenzi to be a good mother. I'm not really an adherant to the 'example' theory though in some cases it may help- or not. Case in point- Juju at Howletts(UK) came there as a small baby, grew up as the youngest in their group and was the first to become pregnant. Reared her baby perfectly. The three older females all gave birth subsequently in the ensuing months but despite Juju's example, all 3 had to have their babies handreared. Possibly they were past the formative 'learning' stage though, as they were fully adult. All three learnt to mother-rear with later babies though. Case 2; Romina. Grew up in Rome Zoo with single male. Never saw a baby. Reared her first/only baby (born when she was already a full adult) at Bristol Zoo perfectly. She then later acted as surrogate mother to another baby too.
 
Interesting abou Rigo/Yuska. If he mated okay why did he never father more offspring apart from Ya Kwanza ?

Rigo never knew how to mate properly, and was only seen mating with Yuska and Johari in the early 2010’s, although at that time both females were on contraception. The mating witnessed though was very gentle, and they’re not even sure he mated properly.

As for why Mbeli didn’t conceive. I’d assume she had been placed on contraception while still in the Kibabu troop and this was probably still wearing off.

Mbeli was on contraception at the time. None of the females were off contraception I believe.
 
The question remains why Buluman was infertile. Was it related to catching mumps and /or low testosterone levels possibly. A male doesn't know he's infertile, so a normally active group leader will not allow another male to mate any his females even if he can't/doesn't father any young himself.

I’m thinking it was something to do with his personality. He was very laid back and quite a gentle male, especially around the other gorillas. Low testosterone levels might explain it and also contribute to his infertility?
 
I’m thinking it was something to do with his personality. He was very laid back and quite a gentle male, especially around the other gorillas. Low testosterone levels might explain it and also contribute to his infertility?

I believe so. I have seen a few other males that behaved like that. Joe in Twycross(UK), Assumbo in Rostock and Mumbah in Columbus USA are a few I can name. All had in common, a gentle quiet nature, unlike most typical males, and all were non-breeders.
 
Rigo never knew how to mate properly, and was only seen mating with Yuska and Johari in the early 2010’s, although at that time both females were on contraception. The mating witnessed though was very gentle, and they’re not even sure he mated properly.

Thanks for the explanation.
 
I was just doing some random research on Taronga's gorillas and found out that Mary (who was 16); died weeks after her foot was amputated in jan 1974. Her foot was amputated after it got severely infected.

Regarding Melbourne's troop:

Buluman died in April of 1998 after he failed to recover from a foot wound.

He lived with Yuska, Betsy, Buzandi and Bambuti. At the time of his death, Motoba lived seperate, as did Julia and G Anne. The zoo at the time planned for Motoba to be 'reunited' with his two offspring and for the two Jersey girls to be introduced.

It may have been that Buluman accepted Motoba only when he was younger, but once Motoba matured, he was kicked out. Since he sired Bambuti in 1993, when he was 10, it makes sense that he would be kicked out of the group soon afterwards, once he entered his teens.
 
I was just doing some random research on Taronga's gorillas and found out that Mary (who was 16); died weeks after her foot was amputated in jan 1974. Her foot was amputated after it got severely infected.

Regarding Melbourne's troop:

Buluman died in April of 1998 after he failed to recover foot wound.

He lived with Yuska, Betsy, Buzandi and Bambuti. At the time of his death, Motoba lived seperate, as did Julia and G Anne. The zoo at the time planned for Motoba to be 'reunited' with his two offspring and for the two Jersey girls to be introduced.

It may have been that Buluman accepted Motoba only when he was younger, but once Motoba matured, he was kicked out. Since he sired Bambuti in 1993, when he was 10, it makes sense that he would be kicked out of the group soon afterwards, once he entered his teens.

I read an article many years ago that detailed how Motoba was not allowed access to his offspring as he was a boisterous adolescent and they felt the sedate silverback was a safer option. Gorillas were a rarity in Australasian zoos and they were VERY cautious about the safety of infants.

Motoba successfully mated with the females, which was what he was brought in to do and the troop soon had an infant female, as well as Betsy’s juvenile son that had been reintroduced to the troop. The separation from Buluman would have been difficult to reverse. Following his maturation into young adulthood, I’d assume Motoba would have posed a bigger threat to the docile Buluman than the other way around.
 
Note, his name is MotAba. I agree with the guess that the separation was more likely to be for Buluman's safety and wellbeing than for his, the impression I get is that he would have easily dominated Buluman.
 
I read an article many years ago that detailed how Motoba was not allowed access to his offspring as he was a boisterous adolescent and they felt the sedate silverback was a safer option. Gorillas were a rarity in Australasian zoos and they were VERY cautious about the safety of infants.

Motoba successfully mated with the females, which was what he was brought in to do and the troop soon had an infant female, as well as Betsy’s juvenile son that had been reintroduced to the troop. The separation from Buluman would have been difficult to reverse. Following his maturation into young adulthood, I’d assume Motoba would have posed a bigger threat to the docile Buluman than the other way around.

I agree, Motaba's separation was likely due to him being young silverback and a potential threat to his children. Apparently, Motoba was rather laid back as he grew older. Buluman was a much more gentle silverback and as articles mentioned he was the best father figure they had. Much better than a young, energetic teenager that Motaba was.
 
I agree, Motaba's separation was likely due to him being young silverback and a potential threat to his children. Apparently, Motoba was rather laid back as he grew older. Buluman was a much more gentle silverback and as articles mentioned he was the best father figure they had. Much better than a young, energetic teenager that Motaba was.

It was an unnatural social situation given a male Motaba’s age would never find himself leading a troop; while he was also at the age where his father would be kicking him out given he’d be seen as a threat and would be starting to antagonise the females (Fataki was becoming aggressive to Mouila towards the end of his time in the Taronga troop).

Buluman clearly benefited from the combination of the minimal socialisation he received in his wild natal troop, combined with his peer-raising alongside Betsy. Combined with his patience, he was the ideal foster father to Buzandi and Bambuti and consequently, they’ve assimilated into troops of their own, where they’ve both bred.
 
It was an unnatural social situation given a male Motaba’s age would never find himself leading a troop; while he was also at the age where his father would be kicking him out given he’d be seen as a threat and would be starting to antagonise the females (Fataki was becoming aggressive to Mouila towards the end of his time in the Taronga troop).

Buluman clearly benefited from the combination of the minimal socialisation he received in his wild natal troop, combined with his peer-raising alongside Betsy. Combined with his patience, he was the ideal foster father to Buzandi and Bambuti and consequently, they’ve assimilated into troops of their own, where they’ve both bred.

I believe they ended up separating both Mzuri and Motoba from the main group shortly before Mzuri's departure to Jersey in 1993. At the time they lived in the current gorilla enclosure whilst the other group lived in the grottos (which also held Orangutans).

Buluman was apparently extremely patient. I believe there was a story about him and a butterfly?; he was incredibly gentle for a silverback. Although he wouldn't have posed harm to Motaba, it's likely Motoba may have been perceived as a threat to Buluman. And Buluman was the best leader for the group, especially for the youngsters, being patient and gentle.
 
The separation from Buluman would have been difficult to reverse. Following his maturation into young adulthood, I’d assume Motoba would have posed a bigger threat to the docile Buluman than the other way around.
That is pretty much the crux of it. Buluman was very quiet and obviously a safer bet as a group leader around the babies. Though I suspect Motaba would in fact have been okay with them too. The better scenario perhaps would have been to leave Motaba in the group until he challenged Buluman and then remove Buluman. But this was early days for breeding in Australia.
 
That is pretty much the crux of it. Buluman was very quiet and obviously a safer bet as a group leader around the babies. Though I suspect Motaba would in fact have been okay with them too. The better scenario perhaps would have been to leave Motaba in the group until he challenged Buluman and then remove Buluman. But this was early days for breeding in Australia.

I believe the decision was first and foremost based around Buzandi. He was initially handraised and while successfully reintroduced to the troop, did not have his mother's protection. Case in point she knocked out one of his teeth when he was getting too boisterous around Bambuti (who she did care for). Introducing Motaba was a risk they chose not to take as while a mother would have the nous to protect her infant from the antics of an adolescent male, it was an unknown if Betsy would have done this.
 
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