Australasian Western Lowland Gorilla Population

[Pertinax]

The obvious imports needed in the short term are:

0.2 at Melbourne
0.1 at Mogo

Yes, that is all that's needed short term really. It would mean at Melbourne Otana had a reasonable -sized group to rule over- he would settle down and become a model silverback leader, everybody would sing his praises in that direction and forget about his earlier transgressions- I have seen this happen several times in European groups. Buzandi is one example.

 

[Jambo]

Our region’s population could easily be increased with females such as Mbeli and Kipenzi taken off contraception; but given how so many of our gorillas are related, your idea would bring in some much needed new genetics.

The obvious imports needed in the short term are:

0.2 at Melbourne
0.1 at Mogo

Long term, Taronga should look at either importing a new male to breed with Mbeli and Fikiri (and retiring Kibali with his three sons); or importing a new female to breed with Kibali given he now only has one reproductively viable female in his troop.

Our region’s population could easily be increased with females such as Mbeli and Kipenzi taken off contraception; but given how so many of our gorillas are related, your idea would bring in some much needed new genetics.

The obvious imports needed in the short term are:

0.2 at Melbourne
0.1 at Mogo

Long term, Taronga should look at either importing a new male to breed with Mbeli and Fikiri (and retiring Kibali with his three sons); or importing a new female to breed with Kibali given he now only has one reproductively viable female in his troop.

Melbourne appear to be trying to 'increase' the numbers in their troop with breeding Kimya, but long term this isn't going to work out. I'd like to see Melbourne bring in two females from overseas; there's a lot of surplus females in Europe to work from. Maybe a large joint import with Adelaide (similar to Taronga's back in 1996) would work. Adelaide could receive an already cohesive troop and Melbourne could receive some of their younger, surplus females.

Mogo could receive Kanzi as they're in need of another female; and the best option for Taronga seems to be importing an entirely new male and retiring Kibali and his three sons; Orana has the space for another bachelor group, or Sydney Zoo could take them, as they've shown interest in obtaining gorillas in the future.

 

[Zorro]

It would be nice if Adelaide jumped on board about now and even Perth zoo

 

[Zoofan15]

It would be nice if Adelaide jumped on board about now and even Perth zoo

Adelaide are planning to hold a breeding troop, though this will still be a few years away. I think they'd be more use to the region by holding bachelor males; with Taronga, Mogo and Melbourne importing females and continuing to breed. Taronga can accomodate their current cohort of young males in their proposed Congo development, but future Taronga born males will need housing in the region.

 

[Zorro]

Adelaide are planning to hold a breeding troop, though this will still be a few years away. I think they'd be more use to the region by holding bachelor males; with Taronga, Mogo and Melbourne importing females and continuing to breed. Taronga can accomodate their current cohort of young males in their proposed Congo development, but future Taronga born males will need housing in the region.

Perhaps some more of the regional zoo like Mogo could come on board?

 

[Zoofan15]

Perhaps some more of the regional zoo like Mogo could come on board?

Mogo have a troop of 1.3 gorillas they're trying to breed from. They could surely benefit from importing a new female as only one is reproductively viable and a full sibling to Kimya at Melbourne.

It's a shame that Sydney Zoo have apparently canned their plans to acquire them as this has had a flow on effect to Orana, who are now no longer planning to acquire a breeding troop (also partly due to financial reasons).

Although I'm not aware of Perth planning to acquire them, they may be wise to consider your suggestion given they'll need to replace their elephants with an equivalent drawcard. I think they may lose out to Indian rhinoceros however.

 

[Jambo]

Mogo have a troop of 1.3 gorillas they're trying to breed from. They could surely benefit from importing a new female as only one is reproductively viable and a full sibling to Kimya at Melbourne.

It's a shame that Sydney Zoo have apparently canned their plans to acquire them as this has had a flow on effect to Orana, who are now no longer planning to acquire a breeding troop (also partly due to financial reasons).

Although I'm not aware of Perth planning to acquire them, they may be wise to consider your suggestion given they'll need to replace their elephants with an equivalent drawcard. I think they may lose out to Indian rhinoceros however.

There's really no other females for Mogo to import (within the region) besides Kanzi. They still have a chance to breed from Kipenzi as she hasn't been taken off contraception yet. They're apparently still attempting to breed from 43 year old Kriba, which makes sense as an offspring of Kisane and Kriba is more valuable compared to one of Kisane and Kipenzi. It would also be beneficial for Kipenzi to witness the raising of a younger sibling; but i'm confident she'll do well with the assistance of her mother.

Sydney Zoo has the space for Gorillas; but I believe they currently have Baboons in their 'planned' enclosure. If really desired, space could be found, although I don't think Sydney will hold more than a bachelor group if they do.

Orana planned to display their breeding troop in the enclosure that temporarily held Auckland's Orangutans; so they do have the space alongside their bachelor troop. Financial issues were likely a key part to the canning of the import, which is quite a shame as it would've introduced new genetics from overseas which the region especially needs at the moment.

 

[Pertinax]

I'd like to see Melbourne bring in two females from overseas; there's a lot of surplus females in Europe to work from.

Don't forget though that younger females in European groups that need to transfer out are still in demand to embellish and/or start fresh breeding groups in other European zoos too. They haven't reached the stage where nobody knows what to do with them (the females that is- different story with males). But two(or even three) new females to Australia would still be a reasonable transfer request.

 

[Abbey]

I thought i'd share this interesting little TV documentary on Melbourne's Mzuri for those interested.

It details Mzuri's birth and how he grew up; being hand raised. The doco also features Buzandi near the end, who was also being hand raised. A lot of intriguing information on Melbourne's troop back then too.

Thank you for sharing this, it's remarkable how things have changed in zoo practice since Mzuri's birth - I didn't realise just how much free contact there was even with adult gorillas back then. The doco does, as you've said, show that even by Buzandi's birth things were starting to change. I see the benefit in handrearing a gorilla infant to allow the baby to survive, although I can definitely see why animals in that position end up so humanised. Despite the similarities in DNA, there is obviously a wide behavioral gap between being a human and being a gorilla.

 

[Zoofan15]

Thank you for sharing this, it's remarkable how things have changed in zoo practice since Mzuri's birth - I didn't realise just how much free contact there was even with adult gorillas back then. The doco does, as you've said, show that even by Buzandi's birth things were starting to change. I see the benefit in handrearing a gorilla infant to allow the baby to survive, although I can definitely see why animals in that position end up so humanised. Despite the similarities in DNA, there is obviously a wide behavioral gap between being a human and being a gorilla.

The behavioural discrepancies between being a chimpanzee and being a gorilla are even vast enough to leave a lasting impact. Julia’s socialisation with chimpanzees in her younger years left a legacy of behaviours that appeared defiant to a silverback when she should have been showing submission.

Buzandi has proved to be a successful silverback, mating with several females; while Bambuti has similarly assimilated successfully into her troop, producing offspring of her own.

Melbourne had three births close together in 1999-2000, which created the unique phenomenon of a gorilla crèche. This was beneficial to the infants by upgrading their rearing from handraised to peer raised - a luxury Mzuri didn’t have.

 

[Jambo]

Don't forget though that younger females in European groups that need to transfer out are still in demand to embellish and/or start fresh breeding groups in other European zoos too. They haven't reached the stage where nobody knows what to do with them (the females that is- different story with males). But two(or even three) new females to Australia would still be a reasonable transfer request.

It would be quite reasonable for Melbourne to import two females. I see the chances of Melbourne just continuing their group with only Kimya as the breeder, very low. It's likely new genetics (from the female side) will be brought in; although there's pretty much no options from within the region, so they'll have to be from outside.

Melbourne had three births close together in 1999-2000, which created the unique phenomenon of a gorilla crèche. This was beneficial to the infants by upgrading their rearing from handraised to peer raised - a luxury Mzuri didn’t have.

That was the whole directive! They welcomed the three gorilla infants all within the space of five months, and two of them (Ganyeka and Johari) were born only three days apart. All three were raised together and were quite close, and it was noted upon their return to the main group, they often had different mothers at different times eg. at one point Johari would be getting carried around by Yuska, and next she'd be one the back of Betsy. It would've been quite a dynamic group to see to say the least.

 

[Zoofan15]

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Historical Timeline - Australasia’s Gorillas: Part 1 (1950’s-1990’s)​

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1950’s:

In 1953, a failed attempt by Taronga Zoo to import gorillas was detailed in which a game hunter spent a year capturing eight young gorillas in West Africa. Australian biosecurity regulations dictated the gorillas must spend three months in a non native country due to the risks of yellow fever. The eight gorillas were quarantined in the Canary Islands, but the seven month wait for a ship caused them to die of ill health (brought on by the climate).

The first gorilla in Australasia was imported by Taronga Zoo 08/06/1959. He was a male named King Kong, who was estimated to have been born 1951 in the wild.

—————————————————

1960’s:

Taronga Zoo imported two gorillas (one male and one female) 18/08/1960. They were named George Kong (1958) and Mary Kong (1957).

Taronga Zoo imported five young gorillas (two males and three females) 18/10/1961. They were all wild caught in Cameroon. One of the females died shortly after on 11/11/1961. The remaining four were named Little John (1958), Buluman (1958), Annabella (1958) and Betsy (1959).

King Kong died at Taronga Zoo 29/10/1968 from chronic pancreatitis.

—————————————————

1970’s:

Little John died at Taronga Zoo 09/06/1972 from intestinal and glomerular nephritis.

Melbourne Zoo imported two young gorillas (a male and a female ) 23/05/1973 and became the second holder of this species in the region. They were named Rigo (1970) and Yuska (1971) and were wild caught in Cameroon.

Mary Kong died at Taronga Zoo 02/01/1974 from chronic nephritis. Her right leg had been amputated the previous month after becoming ulcerated.

Anabella died at Taronga Zoo 13/09/1977 from unknown causes.

George Kong died at Taronga Zoo 04/10/1977 from aspiration of vomitus.

—————————————————

1980’s:

Taronga Zoo phase out gorillas with the transfer of Buluman and Betsy to Melbourne Zoo 15/10/1980. An agreement was made between the zoos that Melbourne would focus on gorillas; while Taronga would focus on chimpanzees. This was based on the recognition that reproductive success was enhanced by keeping them in groups rather than pairs.

Rigo and Yuska produce a male infant named Ya Kwanza at Melbourne Zoo 03/06/1984. The infant is the first of his species born in Australasia and the first of his species born through IVF.

—————————————————

1990’s:

Melbourne Zoo imported a male gorilla from Jersey Zoo 29/03/1990. He was named Motoba (23/12/1983) and was captive born at Jersey Zoo.

Motoba and Betsy produced a male infant named Buzandi at Melbourne Zoo 30/12/1991.

Melbourne Zoo exported Ya Kwanza to Jersey Zoo 18/06/1993.

Motoba and Betsy produced a female infant named Bahasha at Melbourne Zoo 23/04/1994.

Taronga Zoo imported a troop of ten gorillas from Apenheul Primate Park 06/12/1996. They were named Kibabu (25/05/1977), Mouila (1972), Kriba (09/08/1979), Frala (20/06/1981), Shinda (14/06/1991), Kijivu (18/03/1993), Haoko (21/08/1993), Anguka (28/10/1994), Safiri (06/07/1996) and Shabani (20/10/1996).

Melbourne Zoo imported two female gorillas from Jersey Zoo 07/12/1997. They were named G-Anne (08/06/1979) and (Julia (1982). G-Anne was captive born at Oklahoma City Zoo and Julia was wild born.

Kibabu and Frala produced a male infant at Taronga Zoo 07/03/1998. The infant died 30/03/1998.

Buluman died at Melbourne Zoo 30/03/1998. At an estimated 40 years of age, he was the oldest gorilla in Australia.

Kibabu and Frala produce a female infant at Taronga Zoo 25/06/1999. The infant died 26/06/1999.

Motoba and Yuska produced a male infant named Ganyeka at Melbourne Zoo 28/11/1999.

—————————————————

Part 2 will cover the 2000’s-2020’s
Dddf

 

[Zorro]

I find it perplexing that the US and European populations are running out of space for their growing population yet we here are going in the opposite direction

 

[Zoofan15]

I find it perplexing that the US and European populations are running out of space for their growing population yet we here are going in the opposite direction

Imports are badly needed - if not for reproductive reasons, than to balance out the social dynamics at troops like Melbourne and Mogo (which have each been reduced to two adult females). The death of a female in either troop (which is not unlikely given they both have elderly females) would reduce the troops to a single adult female which is an unhealthy position to be in.

Melbourne Zoo are apparently looking at imports - though not in the immediate future. Confirmation of Taronga and Adelaide’s exhibit plans would surely give the region more confidence in the availability of future placements - which for males especially, are currently limited (as they are overseas).

 

[Zoofan15]

Historical Timeline - Australasia’s Gorillas: Part 2 (2000’s-2020’s)

—————————————————

2000’s:

Motoba and Julia produced a female infant named Johari at Melbourne Zoo 26/04/2000.

Motoba and G-Anne produced a male infant named Ganyeka at Melbourne Zoo 29/04/2000.

Melbourne Zoo exported Bahasha to Jersey Zoo 01/05/2001.

Taronga Zoo exported Shinda and Kijivu to Prague Zoo 04/09/2001.

Melbourne Zoo exported Buzandi to Hanover Zoo 17/09/2001.

Kibabu and Mouila produced a female infant named Mbeli at Taronga Zoo 05/02/2003.

Kibabu and Frala produced a male infant named Fataki at Taronga Zoo 24/05/2003.

Kibabu and Kriba produced a female infant named Kimya at Taronga Zoo 07/01/2005.

Taronga Zoo transfered Anguka and Safiri to Adelaide Zoo 06/03/2006 for a one year stay, making them the third regional holder.

Adelaide Zoo exported Safiri to Duisburg Zoo 30/05/2007.

Adelaide Zoo exported Anguka to Lisbon Zoo 04/06/2007.

Taronga Zoo exported Haoko to Ueno Zoo 27/06/2007.

Taronga Zoo exported Shabani to Higashiyama Zoo 27/06/2007.

Betsy died at Melbourne Zoo 06/11/2007 at 48 years of age. She set a new longevity record for this species in the region, surpassing Buluman’s 40 years set in 1998.

Kibabu and Frala produced a male infant named Fuzu at Taronga Zoo 08/12/2007.

Kibabu and Mouila produced a male infant named Mahali at Taronga Zoo 18/08/2008.

—————————————————

2010’s:

Taronga Zoo transferred Mbeli to Melbourne Zoo 28/10/2010.

Kibabu and Kriba produced a female infant named Kipenzi at Taronga Zoo 14/01/2011.

Motoba, Yakini and Ganyeka are transferred to Werribee Open Range Zoo 28/10/2011, making them the third regional holder (fourth historical).

Taronga Zoo imported a male gorilla from La Vallée des Singes 24/01/2012. He was named Kibali (25/01/2001) and was captive born at La Vallée des Singes.

Rigo died at Melbourne Zoo 18/07/2013 from a heart attack. At 43 years of age, he set the longevity record for a male of his species in the region which has yet to be surpassed.

Taronga Zoo transferred Kibabu, Mouila, Kriba, Mahali and Kipenzi to Mogo Zoo 20/08/2013, making them the fourth regional holder (fifth historical).

Melbourne Zoo imported a male gorilla from Howletts Wild Animal Park 04/09/2013. He was named Otana (28/01/2001) and was captive born at Howletts Wild Animal Park.

Melbourne Zoo transferred Mbeli and Johari to Taronga Zoo 19/09/2013.

Taronga Zoo transferred Kimya to Melbourne Zoo 10/10/2013.

Kibali and Mbeli produced a male infant named Mjukuu at Taronga Zoo 30/10/2014.

Otana and Kimya produced a female infant named Kanzi at Melbourne Zoo 14/03/2015.

Kibali and Frala produced a male infant named Fabumi at Taronga Zoo 13/05/2015.

Otana attacked Julia at Melbourne Zoo resulting in her death 24/05/2015.

Taronga Zoo exported Fataki, Fuzu and Mahali to Orana Wildlife Park 18/06/2015, making them the fifth regional holder (sixth historical). Mahali had been transferred from Mogo to Taronga prior to the export.

Mouila died at Mogo Zoo 31/10/2015.

Melbourne Zoo transferred G-Anne to Mogo Zoo 12/10/2016.

Kibali and Mbeli produced a male infant named Mwamba at Taronga Zoo 01/09/2017.

Kibabu died at Mogo Zoo 25/08/2018.

Mogo Zoo imported a male gorilla from Howletts Wild Animal Park 01/05/2019. He was named Kisane (18/08/2006) and was captive born at Howletts Wild Animal Park.

Kibali and Frala produced a female infant named Fikiri at Taronga Zoo 06/06/2019.

Yuska (still living) surpasses the regional longevity record of 48 years 10 months and 6 days on 07/11/2019.

—————————————————

2020’s:

Mahali died at Orana Wildlife Park 14/05/2021 from a stomach tumour.

—————————————————

That concludes the historical timeline of Australasia’s Western lowland gorilla population.

As you can see, this decade thus far has been very uneventful compared to the three that preceded it. Hopefully we’ll see births from Melbourne and Mogo in the near future (though both have been trying with their respective females for a while now without success); as well as some imports from Melbourne Zoo.

As well as the prospect of a new gorilla complex at Taronga Zoo (with an increase holding capacity); we will hopefully see a return of gorillas to Zoos SA, with this species detailed in their masterplan.

Summary of Holders

1. Taronga Zoo (1959-1980)(1996)
2. Melbourne Zoo (1973)
3. Adelaide Zoo (2006-2007) Temporary
4. Werribee Open Range Zoo (2011)
5. Mogo Zoo (2013)
6. Orana Wildlife Park (2015)

 

[Zorro]

Historical Timeline - Australasia’s Gorillas: Part 2 (2000’s-2020’s)

—————————————————

2000’s:

Motoba and Julia produced a female infant named Johari at Melbourne Zoo 26/04/2000.

Motoba and G-Anne produced a male infant named Ganyeka at Melbourne Zoo 29/04/2000.

Melbourne Zoo exported Bahasha to Jersey Zoo 01/05/2001.

Taronga Zoo exported Shinda and Kijivu to Prague Zoo 04/09/2001.

Melbourne Zoo exported Buzandi to Hanover Zoo 17/09/2001.

Kibabu and Mouila produced a female infant named Mbeli at Taronga Zoo 05/02/2003.

Kibabu and Frala produced a male infant named Fataki at Taronga Zoo 24/05/2003.

Kibabu and Kriba produced a female infant named Kimya at Taronga Zoo 07/01/2005.

Taronga Zoo transfered Anguka and Safiri to Adelaide Zoo 06/03/2006 for a one year stay, making them the third regional holder.

Adelaide Zoo exported Safiri to Duisburg Zoo 30/05/2007.

Adelaide Zoo exported Anguka to Lisbon Zoo 04/06/2007.

Taronga Zoo exported Haoko to Ueno Zoo 27/06/2007.

Taronga Zoo exported Shabani to Higashiyama Zoo 27/06/2007.

Betsy died at Melbourne Zoo 06/11/2007 at 48 years of age. She set a new longevity record for this species in the region, surpassing Buluman’s 40 years set in 1998.

Kibabu and Frala produced a male infant named Fuzu at Taronga Zoo 08/12/2007.

Kibabu and Mouila produced a male infant named Mahali at Taronga Zoo 18/08/2008.

—————————————————

2010’s:

Taronga Zoo transferred Mbeli to Melbourne Zoo 28/10/2010.

Kibabu and Kriba produced a female infant named Kipenzi at Taronga Zoo 14/01/2011.

Motoba, Yakini and Ganyeka are transferred to Werribee Open Range Zoo 28/10/2011, making them the third regional holder (fourth historical).

Taronga Zoo imported a male gorilla from La Vallée des Singes 24/01/2012. He was named Kibali (25/01/2001) and was captive born at La Vallée des Singes.

Rigo died at Melbourne Zoo 18/07/2013 from a heart attack. At 43 years of age, he set the longevity record for a male of his species in the region which has yet to be surpassed.

Taronga Zoo transferred Kibabu, Mouila, Kriba, Mahali and Kipenzi to Mogo Zoo 20/08/2013, making them the fourth regional holder (fifth historical).

Melbourne Zoo imported a male gorilla from Howletts Wild Animal Park 04/09/2013. He was named Otana (28/01/2001) and was captive born at Howletts Wild Animal Park.

Melbourne Zoo transferred Mbeli and Johari to Taronga Zoo 19/09/2013.

Taronga Zoo transferred Kimya to Melbourne Zoo 10/10/2013.

Kibali and Mbeli produced a male infant named Mjukuu at Taronga Zoo 30/10/2014.

Otana and Kimya produced a female infant named Kanzi at Melbourne Zoo 14/03/2015.

Kibali and Frala produced a male infant named Fabumi at Taronga Zoo 13/05/2015.

Otana attacked Julia at Melbourne Zoo resulting in her death 24/05/2015.

Taronga Zoo exported Fataki, Fuzu and Mahali to Orana Wildlife Park 18/06/2015, making them the fifth regional holder (sixth historical). Mahali had been transferred from Mogo to Taronga prior to the export.

Mouila died at Mogo Zoo 31/10/2015.

Melbourne Zoo transferred G-Anne to Mogo Zoo 12/10/2016.

Kibali and Mbeli produced a male infant named Mwamba at Taronga Zoo 01/09/2017.

Kibabu died at Mogo Zoo 25/08/2018.

Mogo Zoo imported a male gorilla from Howletts Wild Animal Park 01/05/2019. He was named Kisane (18/08/2006) and was captive born at Howletts Wild Animal Park.

Kibali and Frala produced a female infant named Fikiri at Taronga Zoo 06/06/2019.

Yuska (still living) surpasses the regional longevity record of 48 years 10 months and 6 days on 07/11/2019.

—————————————————

2020’s:

Mahali died at Orana Wildlife Park 14/05/2021 from a stomach tumour.

—————————————————

That concludes the historical timeline of Australasia’s Western lowland gorilla population.

As you can see, this decade thus far has been very uneventful compared to the three that preceded it. Hopefully we’ll see births from Melbourne and Mogo in the near future (though both have been trying with their respective females for a while now without success); as well as some imports from Melbourne Zoo.

As well as the prospect of a new gorilla complex at Taronga Zoo (with an increase holding capacity); we will hopefully see a return of gorillas to Zoos SA, with this species detailed in their masterplan.

Summary of Holders

1. Taronga Zoo (1959-1980)(1996)
2. Melbourne Zoo (1973)
3. Adelaide Zoo (2006-2007) Temporary
4. Werribee Open Range Zoo (2011)
5. Mogo Zoo (2013)
6. Orana Wildlife Park (2015)

Thank you for doing this, it appears that the export of so many in the early 2000 really was a set back for the region that its not recoved from perhaps somewhat sort sighted

 

[Zoofan15]

Thank you for doing this, it appears that the export of so many in the early 2000 really was a set back for the region that its not recoved from perhaps somewhat sort sighted

I believe with the four adolescent females Taronga sent to Europe, they already had placements determined when they came to Australia. It was unusual to transfer a whole troop and the troop was split so that the eldest offspring was five; and any that were older remained behind.

As to why we didn’t receive any females in return - I guess Taronga’s troop were flourishing with three breeding females and Melbourne Zoo had four adult females at this time, as well as two silverbacks. What was really needed was new holders, which didn’t come for another decade.

 

[Zorro]

I believe with the four adolescent females Taronga sent to Europe, they already had placements determined when they came to Australia. It was unusual to transfer a whole troop and the troop was split so that the eldest offspring was five; and any that were older remained behind.

As to why we didn’t receive any females in return - I guess Taronga’s troop were flourishing with three breeding females and Melbourne Zoo had four adult females at this time, as well as two silverbacks. What was really needed was new holders, which didn’t come for another decade.

It appears they were badly managed this end of things

 

[Zoofan15]

It appears they were badly managed this end of things

By the end of 1997, Melbourne Zoo surely had one of the most challenging gorilla combinations the world has ever seen. They had three silverbacks (all housed separately), four adult females, an adolescent male and a juvenile female. Of the seven adults, only one had been mother raised and there were multiple social issues.

Taking on Julia and G-Anne was a challenge. By virtue of Motoba’s tolerance, they were accepted for their social deficiencies that have seen two other (albeit young and inexperienced ) silverbacks reject them from their troops.

On hindsight, it would have been better if Melbourne Zoo had received two mother raised females from Europe. Presumably these weren’t available and they took what they were offered, but it certainly contributed to their inability to form a successful troop.

 

[Jambo]

By the end of 1997, Melbourne Zoo surely had one of the most challenging gorilla combinations the world has ever seen. They had three silverbacks (all housed separately), four adult females, an adolescent male and a juvenile female. Of the seven adults, only one had been mother raised and there were multiple social issues.

Taking on Julia and G-Anne was a challenge. By virtue of Motoba’s tolerance, they were accepted for their social deficiencies that have seen two other (albeit young and inexperienced ) silverbacks reject them from their troops.

On hindsight, it would have been better if Melbourne Zoo had received two mother raised females from Europe. Presumably these weren’t available and they took what they were offered, but it certainly contributed to their inability to form a successful troop.

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.