Chester Zoo Bornean Orangutans

Pertinax said:
Taun. To be a real 'Ape Freak' you've just gotta keep up...;)

Let me guess, I think your principal favourite species are Gorilla, Orangutan, also okapi & maybe Indian & Black rhino?- how close am I? (same as me....;);))
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I know, I get lost in this world sometimes :p To much going on in life that I sometimes miss things!

I would say you where very close, but add Gibbons to that list (only real reason I visit Twycross & the Gorilla's offcourse! ;))
 
I visited Chester on Friday , no Bornean orangs in sight . The young Sumatran Padang is now obviously a male , facially , with a ginger beard developing . One of the Sumatran females was moving actively high up in in the back enclosure with her baby hanging on tight , good to see such natural behaviour . The adult male Sumatran was also sat high up in the side enclosure , surveying the world .
 
Bele said:
The young Sumatran Padang is now obviously a male , facially , with a ginger beard developing
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Padang is quite likely to stay at that stage for a long while to come, especially if he continues living with his father. Some people think a younger male's development can be supressed while he is kept with an adult male- it seems at least partially so.
 
Indeed, if 2 sexually mature males are maintained in one social group, the male lesser in age will not exhibit the full markings of a sexually mature and dominant adult. In this setting the lesser aged adult is being suppressed by the dominant adult.

This biologically induced phenomenon is - perhaps - designed not to challenge the position of the dominant adult in the breeding stakes with available and receptive females and reducing the potential for conflict and fighting between 2 fully dominant adult males.
 
Kifaru Bwana said:
Indeed, if 2 sexually mature males are maintained in one social group, the male lesser in age will not exhibit the full markings of a sexually mature and dominant adult. In this setting the lesser aged adult is being suppressed by the dominant adult.

This biologically induced phenomenon is - perhaps - designed not to challenge the position of the dominant adult in the breeding stakes with available and receptive females and reducing the potential for conflict and fighting between 2 fully dominant adult males.
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This is interesting. Can you direct me to the scientific evidence of this phenomenon? Does it occur in the wild? I would have thought not as orangs are largely solitary. Is it mediated by pheromones? *edit

It isn't design. My hypothesis would be that young males who respond in this way have an evolutionary advantage in that they do not put themselves at risk from older males when they are unlikely to have significant reproductive success, whilst simultaneously perhaps benefitting from association with the older males. The advantage to the old male is obvious.

Edit:
http://pin.primate.wisc.edu/factsheets/entry/orangutan/behav
 
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The chat about Puluh and his son Padang is very interesting, and I think Pyhathrix's hypothesis makes good sense.

Puluh (born 23 Sept 1988) was actually the same age Padang is now (10) when his son was born on 22 Nov 1988. Given that orang's gestation period is 8.5 months, that'd mean Emma conceived Padang around about March 1998 time ....... when Puluh was still only 9 !

I wonder if such a young male would be breeding so quickly in the wild (obviously it's rather different in captivity where they're thrown together) ? ...... potentially one who'd only left his mother a year or so previously ? Somehow, I think not ...... would such a juvenile male appear attractive to females ? ........ would he have even established a secure territory of his own by then ? ....... would he be mature enough to scare off rival males so soon ?
 
GillP said:
I wonder if such a young male would be breeding so quickly in the wild (obviously it's rather different in captivity where they're thrown together) ?
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I believe there are three main 'phases' in the life of a male Orangutan(either species)

1. Infant/juvenile growing phase. Up to about 9.

2. Subadult phase, smaller size & unpadded (as Padang currently is.)

3. Fully adult mature male with long hairy coat & pads. German word for this(we have no english equivalent) is 'Backenwulster' Starts anywhere between 12-18 years but varies a lot.

The subadult phase can last a very long time circa 9 years in some Sumatrans.(Borneans seem to mature rather earlier) Even Puloh at Chester without an older male present (at least latterly) did not develop his pads till about 18, though he was full sized several years beforehand.

I also think in the wild many 'consortships' (temporary male/female association) occur between adult females and males in the subadult phase(I've seen photos of this) and these males may even father a higher percentage of the young than the much older males (in McKinnon, 'the Red Ape'). The really big adult males roam long distances around the forest and their territorial 'longcalling' means any younger male 'in a relationship' can quickly make himself scarce if he wants to avoid conflict.

However the inhibition of full development actually works, I think its only a product of captivity, possibly caused by the(invisible) psychological stress of living with an older male which wouldn't happen in the wild.
 
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Not too long ago, I have read an article about orang utan research in the wild which confirmed that the delayed developments of young males happens in the wild too - there seem to be 2 strategies followed by males: either maturing as fast as possible with the goal of being able to compete with the large males, or second staying the second phase menthioned by Pertinax for a long time with the goal of being seen as no competetion by the big males, therefore being accepted by them in the presence of the females and getting mating opportunities through that.

The social system of orang utans is a lot more complex then just describing them as "solitary" - females in one area seem to be mostly related and spending time with each other when food sources allow this, young males in phase 2 stay close to the female/infant-pairs or groups, and the big males travel alone, searching for food and females in heat. The social groups of related females in Chester aren`t that unnatural, just in contrary.
 
Hi Fellas/Lasses,

Whereas, I hold Pertinax in high esteem on the subject of great apes, I will refrain to comment further on the subject untill I manage to get to read up on the ecological field data for both Sumatran and Bornean orangs.

My hypothesis was somewhat based on field data, however I cannot - at this moment - recall my reading it where ... I will get back to you guys and girls when I do so. It seems that Yassa has seen similar evidence as I, and so the issue is still in contention.

Regards,

K.B.
 
Yassa said:
The social system of orang utans is a lot more complex then just describing them as "solitary" - young males in phase 2 stay close to the female/infant-pairs or groups, and the big males travel alone, searching for food and females in heat. The social groups of related females in Chester aren`t that unnatural, just in contrary.
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yes, they are quite complex socially in the wild and seem to have various strategies as far as mating and partnerships is concerned. In the captive situation, the Studbook describes them as 'best treated as a solitary species capable of adaptatation to sociable group living' (or similar)

I think the current Sumatran group at Chester(and probably in some other zoos too) perhaps fairly closely mirrors the set-up in the wild except they are living in an enclosure rather than several square kilometres of forest.

Some males in captivity do finally attain the 'backenwulster' stage of full development even if there is another older male living nearby and its difficult to prove in those cases if their development was really supressed, or just late anyway. the advanced age of 18 years seems the typical age for a Sumatran male to develop his pads while in Borneans it normally seems earlier, from 12-14 years of age.
 
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What about the the situation at Blackpool where there is a reasonably natural grouping of females - hand-reared mother in her 20's with 12 and 6 year old daughters , both mother-reared . The young male Ramon who should be physically capable of breeding , is dominated and bullied by the adult female . I was told that staff hope he will mature and then be dominant over the females , or is the female's dominance more likely to supress his maturing ? I wonder if future beeding would be more likely with the introduction of a new older male .
 
Bele said:
I was told that staff hope he will mature and then be dominant over the females , or is the female's dominance more likely to supress his maturing ? I wonder if future beeding would be more likely with the introduction of a new older male .
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I believe Ramon was small & a bit sickly when he was imported from (I think) St Petersburg in Russia- so its not surprising if he is growing rather slowly and having a few problems.

Also Victoria- the old female- has been there a lot longer than any of the others so she is undoubtedly boss. Even if she dominates Ramon until he's bigger and stronger, maybe they will still mate? I doubt that she will supress his maturing as a male might do. But an older, stronger adult male would certainly promote quicker breeding I'm sure.
 
There is nothing on the website, which surprises me. I could understand if the baby was ill or even being hand-reared, but he/she looks fine and Leia seems to be doing a good job. Is it possible that Martha is really going to have another infant too, and they want to announce both births together? That would be a winner in the media, particularly as their silly season approaches - of course the zoo thinks of it as peak visiting time.
I think it is a real criticism of the zoo management and their design philosophy that they haven't even put up a notice by the viewing windows for the Bornean orangs - of course if they did, it would slow the flow of visitors through RotRA even more than the design of the building does now. But the opportunity to do so some real public education is being wasted.
I did see a keeper leaving just after I entered RotRA on Saturday morning, but I was peering through the windows which were badly steamed up, and it was only after she had disappeared that I realised that I should have asked her about Leia's baby :o

Alan

PS Just had an idea! We could give the baby a name - purely unofficially and temporarily of course - how about 'Izit'?
You know "Izit named yet?", "Izit a boy or a girl?" etc Get it? :D
 
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gentle lemur said:
PS Just had an idea! We could give the baby a name - purely unofficially and temporarily of course - how about 'Izit'?
You know "Izit named yet?", "Izit a boy or a girl?" etc Get it? :D
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I like the name Izit as i don`t think it would matter if its a girl or boy with that name.
 
beckiscott said:
Haha great name, love it!

It's a shame the news (both good and bad) doesn't get posted sooner on the zoo website and enclosures; hopefully it's something they're aware of and working on?! (fingers crossed)
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Well seeing as all the senior management of the zoo read this forum i think they have an idea as to whats been said about the zoo.
 
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