I am surprised that castration of great apes is allowed or even promoted. A form of physical mutilation which creates life-long and irreversible behavioral changes. Gorilla is mentally much above an average working ox.
The fact you think a male having 'half cousins' that are well represented is of little consequence in and of itself is a ridiculous statement. All founders need equal representation is a correct statement, but if you allow the breeding of an animal that comes from not one but two overrepresented bloodlines then you are going to, if anything, reduce the 'equal representation' you point out the gene pool needs. The fact you choose to point out the only one of Ajabu's six great-grandparents that isn't well represented says enough. Mintha may not be very well represented in the gene pool, but Bongo, Baby Doll, Kisoro, Boma and Massa all very much are, as is Ajabu's grandfather Matze. Males have remained intact until the age of 12 at Taronga...that's great! But that's only one example. There are quite literally dozens of examples where it hasn't worked, especially in instances of multiple male offspring which is so common in captive gorilla groups. Artis, Beauval, Prague, GaiaZOO...these are all examples of zoos in which castration of younger males has allowed them to remain in the group for far longer than would normally be allowed, and thus reduces the need to export surplus animals further and further afield (look at the gorillas that moved from Apenheul to Al Ain, the gorillas that are intended to move to Orana from various zoos in Europe, the ones that have been sent to Ragunan, to Belo Horizonte...the list goes on!) Let's maybe leave the studbook's choices to, well, the studbook....
It's a system that works...granted vasectomising the males would be an option in multi-male/multi-female species such as chimpanzees and bonobos, but given the physical change that a male gorilla goes through and the tendency to only have one sexually mature male to multiple females means, with the combination of a lack of interested new holders who are ok with having an all male group and the overwhelming majority of males compared to females, that they had to get a little more creative. It would be that or euthanasia, and I know which of the two options I would go for personally...
Sorry, but 'this is practical' is usually the opposite of 'this is ethical'. I don't want to go off-topic into gorilla management, but among options are: redesigning exhibits with visual barriers, to reduce fricton between adolescent and adult males, and forcing some breeding zoos to switch to non-breeding groups, especially some city centre zoos with old, substandard to barely adequate ape exhibits. Bachelor groups are not even a natural social unit of gorillas. Adolescent males stay in a group long after sexual maturity, or live alone for years waiting for an open territory. Just as keeping a bird flightless is not acceptable for a species which flies permanently, like a swallow or a falcon, the same way castration would not be acceptable for species with highest developed mental life.
No they aren't, only Ajabu. I think its still not mass castration though- they have done about a dozen so far over a period of about a decade, and none that I know of since Ajabu, who is now 5 years old (today). It is still in the experimental phase. I do not like it but it does provide an option for easier management. I would prefer to see a curb on so much breeding.
I only have a surface level understanding of gorilla behaviour, but wouldn't some of the ideas you bring up cause more harm than castration does? Forcing zoos to go into bachelor groups will in practice require spitting up functional family groups. Furthermore, while it may be true that gorilla males live solitary in the wild, that doesn't mean it is good for their welfare to do so. Castrated gorillas do have functional social lives and are more cohesive in their family groups then intact males (sources below). Castration, therefore, might be the lesser evil here. I do think the comparison with a flightless swallow is exaggerated. A swallow cannot engage in almost all normal behaviour when flightless, while a castrated gorilla can still live a functional social life. Spoiler: References Letang, B., Rietkerk, F., Szánthó, J., Mulot, B., Britton, L., ter Meulen, T., & Sueur, C. (2017). How does castration change integration of immature males in their familial group network in captive western lowland gorillas. Folia Primatologica. Létang, B., Mulot, B., Alerte, V., Bionda, T., Britton, L., ter Meulen, T., ... & Sueur, C. (2021). Social proximities of developing gorilla males (Gorilla gorilla gorilla) in European zoos: The consequences of castration and social composition. Applied Animal Behaviour Science, 234, 105175.
It's preferable to euthanasia of surplus males, which is the alternative option being actively avoided given the increasing problem of a male-heavy population - and one which is no less permanent and irreversible. Unless your stance is that it is better to be dead than castrated.... in which case there's probably not much point debating the matter
Zoos are being 'forced' into keeping bachelor groups to provide homes for all those surplus males that will not be/are not tolerated in their natal groups, that is, nearly all of them by the time they are twelve years old, most long before that. Male gorillas that live solitary in the wild are following a natural behaviour pattern- living in male groups for gorillas in zoos is less than natural- they tolerate it in the main, but with elements of stress and frequent 'fallouts'- often from which there is no return. We don't yet know the longterm effects of castration on male gorillas socially- but they are effectively 'neutered'- so they will presumably play neither a male or female role in the groups they live in. Zoos and the EEP are bound to put a positive spin on what is still a controversial subject.
@Zoofan15: I‘d really like to know how you know that the bachelor groups in Australia are coming along fine. Do you habe any inside knowledge or is that based on the fact that they are housed together? From what I know about bachelor groups in Europe, adult males rarely (maybe never) ‚get along fine‘. They may tolerate each other, but not more, and it happens frequently that tensions escalates and individuals need to be housed alone permanently. I have never seen positive social behavoir between adult males, nor between adult males and young males in a bachelor setting. Only the young ones are playing with each other, but as soon as they mature into silverbacks there is tension everywhere. Id really like to know if there is a bachelor groupof gorillas anywhere in the world that works better. Elephant bulls are much easier in bachelor groups!
In Australia the only bachelor group currently is male Motaba and his two sons Yakini and Ganyeki at Werribee. There also a younger group of 3 males, from Taronga Park/Sydney living in Orana Park in New Zealand- its planned they will move back to Australia, to the other 'new' zoo in Sydney. I don't know if there are any problems with them over there but in Europe males have certainly had to be segregated from the others at both the oldest established Loro Parc and Port Lympne bachelor groups.Once fighting starts, as you said, it escalates and segregation is necessary. In Port Lympne two males(Timbou & Mataki) have to live solitary, segregated permanently both from each other and the other three they formerly lived with. After years alone they are never likely to rejoin the others now. And at Paira Daiza, silverbacks Lomako & Sango started fighting, resulting in Sango being moved to Berlin. Pertinax in Paignton was isolated a few years ago from the other three younger silverbacks and has since lived seperately on a permanent basis. I am waiting for trouble to start among the younger three...
Within Australasia, we also have the bachelor troop at Orana Wildlife Park. Their troop consists of two brothers and their half brother and having spoken to staff who’ve worked with them, they’re getting along well. They have a reasonable sized exhibit and are enriched and stimulated. I’ve heard similar things regarding Werribee’s troop. Recently, Motoba has stepped down as the alpha; to allow his son, Yakini, to lead the troop. The transition was by all accounts, peaceful and mutual on both sides - Motoba was content to step down from the responsibility. It’s interest to hear things have gone sh-its up over in Europe with their bachelor of troops. Whether a bachelor troop works or not would be dependent on many factors: personalities, ages, social backgrounds, quality of enrichment and exhibit space; as well as the presence of external stressors (high volume of visitors). I’m willing to accept the two bachelor troops in Australasia have just been lucky, but either way they’ve worked (without castration).
Yes,it seems so far neither of the Australasian bachelor groups have experienced problems. But there is only a total of six animals. In Europe there are a lot more males housed in groups like this, so more likelehood of examples where they fail, at least partially. Its also possible where there are familial links, as in both Australasian groups, tolerance of each other may last better.
Agreed. I can see Australasia forming a third bachelor troop in the near future from the three young males at Taronga - brothers Mjukuu (2014) and Mwamba (2017); and their half brother Fabumi (2015). If the males within in them aren’t castrated, bachelor troops are a valuable reserve to call up males as and when needed. God knows ZSL have got through them.
Motoba was always going to step down and allow Yakini to take over. Motoba, being a very laidback male, meant that the transition was smooth and there were no problems to worry about. Since then, Motoba has fallen to become the lowest ranking male in the troop. When I visited Werribee last year, the keeper highlighted there were some issues being dealt with at the time between Yakini and Ganyeka. Ganyeka, who in the past hadn't shown any interest in social status, was now beginning to do so. Of course, no bachelor group is going to go without any issues. Being social animals, squabbles and disagreements are inevitable. So far, Australian bachelor groups haven't experienced issues to the extent of those in Europe, but the more bachelor groups formed, the more likely these issues will occur over here.
Recently (at least) two red-crowned cranes (Grus japonensis) hatched at the zoo. Source: Instagram of Prague Zoo (26/04/2021) https://www.instagram.com/p/COIaHpaB-1b/
The parent of these 2 two-weeks old chicks is an old reliable breeding pair. Female Amálka was imported 1998 from zoo Beijing/China, male Albert came from Saitama Zoo/Japan. Albert is pretty dangerous during time when his chicks are young, he can attack you though the netting if you stop at the railing and don´t back off 2 steps when he comes near you. In other news, a lowland tapir calf was born last week. Today he has his premiere for visitors. Lowland tapir EEP population (+300 animals) is currently at its maximum capacity and most collections have breeding stop. Prague was allowed to breed by coordinator only due to rare genetial backround of the parents. Male Tex was imported from San Antonio/USA in 2006 and with exception of his offspring with female Ivana (born at Jihlava zoo), he is unrelated to European tapirs. Female Taluen was imported from Zoo de Guyane/French Guyana in 2019 and her mother is new founder for EEP because her parents were wild born (father was imported from well represented European line). Edit: Unfortunately, giraffe female Eliška died. She was 25 years and 7 months old and second oldest giraffe in Europe. She was leader of Prague herd and very nice to humans and good mother to her 9 calves. Being a face of some past ad campaigns of the zoo, she will be missed by locals.
Prague will soon start the first phase of the reconstruction of hoofstock enclosures in the upper part of the zoo (Przewalski horses, etc...). In future the area will be completely Asia-oriented, Indian rhinos will arrive there, also some smaller Mongolian fauna will be present.
Well if they want to make it "Asia-only" I assume it's the end for Scimitar-horned oryx and Bison, possibly Wisent and Chaco peccary, unless those will be moved elsewhere but space where can they go is very limited and it would require other species to go...but we'll see, there aren't any plans public yet so everything is pure speculation now.
