Australasian Western Lowland Gorilla Population

[Jambo]

Hopefully Melbourne zoo might consider that?

There's two ways they can go.

Either A) they still wish to hold gorillas, and therefore would have to obtain additional females (likely from Taronga).

Taronga only have three females so they'll either offer one (likely Mbeli); two (Mbeli and Johari; with Kanzi sent in return) or all three (Mbeli, Frala and Johari).

Or B) send both Otana and Kanzi to different facilities and take the time to renovate the current complex. Orana (for the former) and Mogo (for the latter) would be the best options for those individuals.

 

[Zorro]

There's two ways they can go.

Either A) they still wish to hold gorillas, and therefore would have to obtain additional females (likely from Taronga).

Taronga only have three females so they'll either offer one (likely Mbeli); two (Mbeli and Johari; with Kanzi sent in return) or all three (Mbeli, Frala and Johari).

Or B) send both Otana and Kanzi to different facilities and take the time to renovate the current complex. Orana (for the former) and Mogo (for the latter) would be the best options for those individuals.

That sounds like an excellent idea!

 

[Zoofan15]

There's two ways they can go.

Either A) they still wish to hold gorillas, and therefore would have to obtain additional females (likely from Taronga).

Taronga only have three females so they'll either offer one (likely Mbeli); two (Mbeli and Johari; with Kanzi sent in return) or all three (Mbeli, Frala and Johari).

Or B) send both Otana and Kanzi to different facilities and take the time to renovate the current complex. Orana (for the former) and Mogo (for the latter) would be the best options for those individuals.

Transferring to Kanzi to Taronga Zoo would be an excellent move; allowing Taronga to form a troop around Kibale and Kanzi (breeding pair); with Frala as an additional post-reproductive female.

At this point in time, I’d expect Taronga’s bachelor troop of adolescent males to be split off given the introduction of Kanzi could cause conflict between Kibale and his sons.

From there, Otana could head up a new troop at Melbourne with Johari and Mbeli; again essentially forming a 1.1 breeding pair. New females could still be imported to supplement either troop.

 

[Swanson02]

Transferring to Kanzi to Taronga Zoo would be an excellent move; allowing Taronga to form a troop around Kibale and Kanzi (breeding pair); with Frala as an additional post-reproductive female.

At this point in time, I’d expect Taronga’s bachelor troop of adolescent males to be split off given the introduction of Kanzi could cause conflict between Kibale and his sons.

From there, Otana could head up a new troop at Melbourne with Johari and Mbeli; again essentially forming a 1.1 breeding pair. New females could still be imported to supplement either troop.

Could taronga send their 3 young males in exchange for Kanzi? Give Taronga space for breeding and a new female?

Attempt to integrate them with Otana? If it doesn't work send Otana elsewhere? Orana?

 

[Zoofan15]

Could taronga send their 3 young males in exchange for Kanzi? Give Taronga space for breeding and a new female?

Attempt to integrate them with Otana? If it doesn't work send Otana elsewhere? Orana?

That’s totally a possibility. The best way to do that would probably be to transfer Kanzi out and leave Otana alone for a short period of time (a transition period). If they brought in the males immediately, he’d be in the frame of mind of leading and troops and potentially resent them.

Considering the males at Taronga are adolescents, they’d be perceived as less of a threat by Otana; and conversely, would have each other for mutual support. It’s a good idea and certainly worth a try in my opinion as it would see all the females housed with a behaviourally optimal silverback; and remove Otana from a breeding situation (arguably what’s happened now).

 

[Swanson02]

That’s totally a possibility. The best way to do that would probably be to transfer Kanzi out and leave Otana alone for a short period of time (a transition period). If they brought in the males immediately, he’d be in the frame of mind of leading and troops and potentially resent them.

Considering the males at Taronga are adolescents, they’d be perceived as less of a threat by Otana; and conversely, would have each other for mutual support. It’s a good idea and certainly worth a try in my opinion as it would see all the females housed with a behaviourally optimal silverback; and remove Otana from a breeding situation (arguably what’s happened now).

How long would that period be? 6 months to a year? Melbourne wouldn't lose Gorillas so that's a bonus. Additionally, if Otana gets violent hopefully the brothers could form a defensive coalition against him.

Then one day in the far future Melbourne could form a new breeding troop with one of Kibale's sons.

 

[Zoofan15]

How long would that period be? 6 months to a year? Melbourne wouldn't lose Gorillas so that's a bonus. Additionally, if Otana gets violent hopefully the brothers could form a defensive coalition against him.

Then one day in the far future Melbourne could form a new breeding troop with one of Kibale's sons.

I think a minimum of three months, but certainly no longer than six months would be sufficient. Aside from allowing Otana’s mindset to transition from silverback/protector mode to bachelor mode; it would generate a desire for the company of (any) gorilla ideally (no guarantees of course).

This was essentially the case for Tsotsi (alpha male chimpanzee). He was introduced to Sandali (from Taronga) not long after his mother and sister left for New Zealand and he wasn’t in the right mindset for meeting an unrelated male (a challenging process in its own right).

I agree the younger brothers (a cohesive trio) should stand up for each other as and when required; with Otana likely emerging as the dominant male at least initially; but perhaps one of the more socially competent males taking over five or so years down the line (my money would be on Mjuuku).

 

[Swanson02]

I think a minimum of three months, but certainly no longer than six months would be sufficient. Aside from allowing Otana’s mindset to transition from silverback/protector mode to bachelor mode; it would generate a desire for the company of (any) gorilla ideally (no guarantees of course).

This was essentially the case for Tsotsi (alpha male chimpanzee). He was introduced to Sandali (from Taronga) not long after his mother and sister left for New Zealand and he wasn’t in the right mindset for meeting an unrelated male (a challenging process in its own right).

I agree the younger brothers (a cohesive trio) should stand up for each other as and when required; with Otana likely emerging as the dominant male at least initially; but perhaps one of the more socially competent males taking over five or so years down the line (my money would be on Mjuuku).

Would Mjuuku be the best male to form a future Troop around too?

 

[Jambo]

Transferring to Kanzi to Taronga Zoo would be an excellent move; allowing Taronga to form a troop around Kibale and Kanzi (breeding pair); with Frala as an additional post-reproductive female.

At this point in time, I’d expect Taronga’s bachelor troop of adolescent males to be split off given the introduction of Kanzi could cause conflict between Kibale and his sons.

From there, Otana could head up a new troop at Melbourne with Johari and Mbeli; again essentially forming a 1.1 breeding pair. New females could still be imported to supplement either troop.

Could taronga send their 3 young males in exchange for Kanzi? Give Taronga space for breeding and a new female?

Attempt to integrate them with Otana? If it doesn't work send Otana elsewhere? Orana?

The switching of Kanzi for Frala and Mbeli essentially gives both facilities a foundation of 1.2 individuals, a breeding pair and a post reproductive pair.

However if we are to assume Melbourne's been hesitant to acquire additional females due to the fears of Otana rejecting them (or worse), this may complicate things in this scenario. Unless management have a change of heart and believe a chance should be taken, this may be the best opportunity to begin to transition him out to a bachelor facility (such as Orana).

Melbourne could then take on Taronga's young males (perhaps temporarily) with the goal of acquiring additional females down the line to perhaps pair with one of those males.

All in all, it essentially depends on whether Melbourne is willing to retain Otana as a breeding silverback (and therefore acquire additional females). This will set the framework for any future decisions made ie. what will happen if they decide yes, or no.

 

[Jambo]

Hey I'll delete this message soon as to not take up space on thread, but with a family troop of WL gorillas, what is the absolute oldest a young male gorilla can remain in the group before the silverback male - vast majority of time (almost entirely these days) his sire - will not tolerate him any longer?

I've seen some very wide range estimates about, but am curious if you guys might share a more fixed sort of age in years or months that would be the limit of being able to remain in his natal group before having to be sent to live in either a bachelor troop or sent to be founder of own troop.

No need to delete the message Steve! Questions are perfectly fine, and welcomed.

In regards to your question, there isn't really a specific number. From what I've seen it can really depend on a variety of factors ie. the individuals personality, temperament of the silverback and others in the troop, the size of the troop, the size of the spaces they have access too, whether there's any infants ect. ect.

Usually it's usually once they hit double digits (ie. following the age of ten). If I was to place a rough range it would probably be between the ages of ten to twelve from what I've seen but it can really differ based on the factors I mentioned above.

Some males are ousted much younger and some males also last longer in their natal groups. However once they exceed the blackback period and become silverbacks (from the ages of ten to fifteen) they're guaranteed to be ousted by the silverback.

 

[Pertinax]

I


Darrill Clements book “Postcards from the Zoo” describe Buluman’s great patience with Betsy, who unfortunately had this habit of screaming hysterically for only minor reasons. This greatly declined upon her move to Melbourne, suggesting that being held with an albeit placid silverback in a 1.1 ratio within a small cage could have been the cause (as opposed to trauma from capture etc) which would present as a lifelong issue.

It’s testament to Motaba that he successfully mated with four socially deficient females, including two of which were previously rejected from Mzuri’s troop (and one of which was later fatally injured by Otana). Youth and inexperience of the silverback has been attributed to those incidents; but Motaba’s youth transcended any expectation we could have had of him.

I would think that was probably exactly the reason for Betsi's behaviour- even with a placid silverback a 1.1. situation is bad as the male can still push the female around if he wants to. This creates permanent tension for the female, hence in Betsi's case over-reaction and screaming. I know of females that have been kept in this 1.1 situation and even after improved housing, will not approach a male for mating throughout the rest of their lives, or stay high up 'out of reach' where the possibility arises.

Motaba was a very 'well-rounded' male having come from a group situation at Jersey (you can see him riding on his mother Nandi's back in the famous 'Jambo and the boy incident' videos). He was a fortunate choice for Melbourne, though Jersey weren't so successful with Mzuri/Ya Kwanza!

 

[Zoofan15]

Would Mjuuku be the best male to form a future Troop around too?

A bachelor troop with his brothers, certainly. He’s the largest of the three adolescents and a well socialised male with a good temperament.

Although Mjuuku would make an effective silverback in my opinion, his half brother Fabumi is more valuable genetically; and while not as confident as Mjuuku, there’s nothing to suggest he wouldn’t excel as a troop leader one day.

 

[Zoofan15]

Hey I'll delete this message soon as to not take up space on thread, but with a family troop of WL gorillas, what is the absolute oldest a young male 'blackback' gorilla can remain in the group before the 'silverback' male - vast majority of time (almost entirely these days) his sire - will not tolerate him any longer?

I've seen some very wide range estimates about, but am curious if you guys might share a more fixed sort of age in years or months that would be the limit of being able to remain in ones natal group as a 'blackback' before having to be sent to live in either a bachelor troop, or sent to be found ones own troop. Also in the lower timeframe range of things, do you guys know some examples of male gorillas being sent away from their natal troops fairly early for an array of seasons - could be wrong but believe Mzuri was an example of this but in his case believe (pretty certain Zoofan15 told me) he was in exchange with JZ for Motaba for Melbourne's troop to have a blackback and eventual silverback (who could sire, but in the interim too as a 'blackback': which he did of course, and thanfully Buluman was a cool chilled 'silverback').

Great question @steveroberts!

Within the region, conflict has begun as early as the adolescent years (Kibabu and Fataki were a particularly fiery duo, which wasn’t helped by Frala’s support of him). Conversely, Mouila’s son remained in his natal troop until much older without issue. He was close to 12 years when he transitioned out.

Mjuuku, Fabumi and Mwamba are all doing well in their father’s troop (with the oldest male turning 11 this year). On our visit, they seemed to be spending the majority of their time together and were keeping out the way of their father, but without the impression of conflict. I’m therefore of the opinion that whole 10-12 years is the typical age (by then, they’re well and truly capable of impregnating females); if the females remain on contraception, then the upper limit (12 years) is usually achievable (personality dependent).

 

[Pertinax]

Great question @steveroberts!

Within the region, conflict has begun as early as the adolescent years (Kibabu and Fataki were a particularly fiery duo, which wasn’t helped by Frala’s support of him). Conversely, Mouila’s son remained in his natal troop until much older without issue. He was close to 12 years when he transitioned out.

Mjuuku, Fabumi and Mwamba are all doing well in their father’s troop (with the oldest male turning 11 this year). On our visit, they seemed to be spending the majority of their time together and were keeping out the way of their father, but without the impression of conflict. I’m therefore of the opinion that whole 10-12 years is the typical age (by then, they’re well and truly capable of impregnating females); if the females remain on contraception, then the upper limit (12 years) is usually achievable (personality dependent).

I see that Kimya has now died at Melbourne...this leaves them just father and daughter. Action needed.

 

[Zoofan15]

I see that Kimya has now died at Melbourne...this leaves them just father and daughter. Action needed.

Yes, from a welfare perspective it’s not acceptable to leave Kimya on her own in this 1.1 pair.

Numerous options have been floated in this thread, including whether Otana could form a bachelor troop with Taronga’s adolescents (with Kanzi sent to Taronga); or whether Taronga’s socially normal, prime aged female (Mbeli) could join Otana and Kanzi.

 

[Pertinax]

How strange this has happened while you have been discussing the future of the Melbourne group. Very bad loss for everybody of course, both the group(now only two animals) also keepers and the zoo as a whole.

I don't know how the zoo would feel about it but the obvious might be as you said for Kwanzi to go to Sydney and Melbourne to form a bachelor group...but maybe they want to continue with a male/female group.

 

[Zoofan15]

How strange this has happened while you have been discussing the future of the Melbourne group. Very bad loss for everybody of course, both the group(now only two animals) also keepers and the zoo as a whole.

I don't know how the zoo would feel about it but the obvious might be as you said for Kwanzi to go to Sydney and Melbourne to form a bachelor group...but maybe they want to continue with a male/female group.

The announcement of the birth of Kipenzi’s second infant at Mogo Wildlife Park sparked a discussion, which continued today with the sad news of Kimya’s passing. It’s a tragic twist of fate; and echoes the passing of Kimya’s elder sister Safiri (1996-2020), who also died in her prime, albeit after producing five infants (three surviving) compared to Kimya’s one.

Unless either zoo is willing to import, that would appear the best option and as has been said, would also resolve the issue of Otana, who isn’t an ideal troop leader.

 

[Zoofan15]

We are seeing cases of females in groups taking over the complete responsibility of babies that have lost their own mothers too. In Europe two zoos, Apenheul and Gaia Park currently have babies that were adopted or taken over by another female (without removal from the group) after their own mother died. Possibly it happens in wild groups as well.

Alloparenting has also been observed multiple times in the Prague troop (Richard era) and more recently at London Zoo.

It’s interesting as after Frala gave birth to Fabumi in 2015; Mbeli, who had given birth herself the year before, made repeated attempts to try and hold Fabumi, but was blocked by Frala at every point and turn. At the time, I had reservations on her intent (thinking of chimpanzees and infanticide); but based on what I’ve since learnt of alloparenting in gorillas and how higher ranking females often try and commandeer the offspring of lower ranking females, I’m of the opinion that Mbeli would have likely raised Fabumi had she been allowed the chance!

 

[Jambo]

It’s interesting as after Frala gave birth to Fabumi in 2015; Mbeli, who had given birth herself the year before, made repeated attempts to try and hold Fabumi, but was blocked by Frala at every point and turn. At the time, I had reservations on her intent (thinking of chimpanzees and infanticide); but based on what I’ve since learnt of alloparenting in gorillas and how higher ranking females especially try and commandeer the offspring of lower ranking females, I’m of the opinion that Mbeli would have likely raised Fabumi had she been allowed the chance!

More specifically an example I remember details Melbourne's trio of gorillas that were born together in 1999/2000.

Yakini, Ganyeka and Johari were all effectively hand raised/peer raised. However when in with the group, it was Betsy (then in her early 40's) who looked after all of the offspring. None of the infants mothers actually really showed in significant interest and Betsy seemed more than happy to raise all three offspring obviously with the help of keeper. There's a great photo online of Betsy piggy backing one of the offspring.

From all accounts the mothers seemed content with this baby sitting and it's really noticeable how much Betsy succeeded in raising the trio. Johari's now in a breeding group at Taronga (albeit an outsider) and the other boys are displaying normal social behaviors in their bachelor group at Werribee.

 

[Tiger91]

Could taronga send their 3 young males in exchange for Kanzi? Give Taronga space for breeding and a new female?

Attempt to integrate them with Otana? If it doesn't work send Otana elsewhere? Orana?

This would be probably the best stop gap, especially since Melbourne seem to have shown no interest with breeding. Making them a bachelor facility until they can work out what comes next would be the best way forward for them. It would also give Taronga a second breeding female, that is a facility that is interested in breeding. Hopefully if they move the males on they can restart breeding and have a few females born.