Lowland Gorillas in Europe 2014

I have a -probably dumb?- question, prompted by the move of Kiki (ok, she is special, but the rest of the Antwerp gorillas are healthy) into a non-breeding group (and orang Barito, where his hybrid companion is on contraceptives). But I don't come from a zoological background, so please be clement.

Why are zoos so anxious to not interbreed?
As long as their homecountries are not safe, the apes cannot be moved regularly back into the wild, if this was the case I would understand.
I don't think a little hybrid gorilla would raise less awareness, or whatever the zoo is trying to accomplish, but it would make a nice "enrichment item" for the group. And when it's time for the offspring to leave and have their own family the hybrid part would be bred out after a few generations anyway.

 

Kumba (Western lowland silverback) at Antwerp is infertile anyway, and Victoria (Eastern lowland) is probably post-reproductive now as well, so currently they cannot breed even if they tried.

 

One of the reasons is the capacity of zoos. A hybrid ape born in a zoo tomorrow may live for 40 years or more. It would need housing and feeding for all this time, effectively preventing the zoo that keeps it from keeping a potential or actual breeding animal.
Hybrids should not be allowed to breed except in very special circumstances, such as the case of Przewalski horses where one of the founders was a hybrid, the influence of that founder has been reduced over the generations but it can never be eliminated now. But in general the genetic purity of the animals should be preserved, so that if their descendants are released into the wild, they will be as well equipped for survival as possible.

Alan

 

There are currently a number of difficulties for the EEP to deal with in managing the captive Gorilla population e.g. genetic management and inbreeding co-efficients, what to do with surplus males, the castration debate etc etc, so that the concept of 'hybrids' would just create yet another problem., As Jabiru states above, it isn't possible anyway, given there are only two(?) Eastern female Gorillas in Zoos - both at Antwerp, with an infertile Western male- this was a deliberate pairing organised to prevent any danger of breeding between the species/subspecies. It also means other females unsuitable for breeding can be added to this group without the need for contraception etc.

 

Thanks for your answers. So, as usual, it's more or less the lack of money and space.

Point taken.

Would a western-eastern hybrid be less fit for release?
I apologize, this is now rather theoretical, because imho no zoo-gorilla is only through breeding prepared for the wild (even though Aspinall certainly did his best). The way I see it, it's a matter of learning and habits, either from other gorillas or from humans?

The genetic purity thing with gorillas reminds me strongly of intermarrying nobility which in the end produces a bunch of sickly gaga-sovereigns

With (Przewalski)horses it's a different matter, they can -here and now- be shipped to Mongolia, and they have to be able to stand extreme temperature differences, be able to cope with less food for a longer time, etc. As we all know race horses are bred for stamina, jumping quality, or dressage elegance, but contrary to gorillas*, there is a wider genetic pool available. Maybe the organizations concerned could facilitate the exchange of gorillas between Europe and the States?

*before any clowns say something: no, gorillas don't need to jump or make elegant ballet moves, they just need to be healthy!

 

A hybrid gorilla would be probably be less fit than than the native subspecies if it were released in the wild - there is probably a reason why eastern lowland gorillas have longer coats and simpler nostrils than western ones, a hybrid with intermediate characteristics would be at a disadvantage in the east and the west.

Your comparison with the mating habits of European royalty is misplaced: the royals intermarried to restrict their bloodline, consequently a prolific pair could pass a faulty gene widely through the stock, as happened with the gene for haemophilia which Queen Victoria carried and was spread into other royal families by her children by Prince Albert.
On the other hand, the aim of studbook keepers for any species is to maintain genetic diversity by avoiding breeding related animals together and by restricting the breeding of animals from prolific breeding lines and encouraging the use of animals from uncommon bloodlines as breeders. To explain, using the example from a previous post, Gugas the male at Belfast is one of the last wild-caught gorillas to be imported, as far as we know he has no close relatives in captivity (in theory DNA testing could confirm this). He has fathered two infants in the past year or so, confirming his fertility, so to establish his unique genes in the captive population the young female Namoki is being sent from Bristol to Belfast where we all hope she will breed with him. Namoki is also genetically important as she is the only child of her mother Romina who is also the only child of a wild-caught pair (although Namoki's father Jock has two other offspring and may have more). Offspring of Gugas and Namoki would be unrelated to most of the other gorillas in Europe and could be sent to virtually any breeding group in the future.
There have been several gorillas sent around the world for breeding purposes, usually males. For example, the sons of Jersey zoo's male Jambo have become the breeding silverbacks at Twycross, Chessington, Zurich, Calgary, Colorado and Melbourne.

Incidentally, you're partly wrong about racehorses too: all thoroughbreds are largely descended from only three stallions imported into England about three hundred years ago, although a much larger number of mares was involved.

Alan

 

Maybe, yes, I have never really thought about that. I assumed it's like with people, some have pale skin, some dark, some are hairier than others. Also, I have no idea about the specific climates in Africa, I just thought everywhere where gorillas live it's hot and humid at day and cold(er) at night, plus two rain seasons.

Good! Hopefully little Namoki can live up to that!

The other way round too?
Anyway, thanx again for answering, I am here to learn, and until you explained that, I had the feeling all European gorillas can be traced back to about the same three or so (great)grandparents.

 

Initially breeding was confined in the 1950'-1960's, to just a very few European Zoos such as Basel and Frankfurt, so initially other groups tended to contain animals from these genetic lines too. But as time progressed more Zoos started breeding from other Gorillas not related to these, so that the gene pool became much wider as a result. But it still ranges from some very over-represented lines, particularly those of some males which bred with a number of females (e.g. Basel/Jersey (Jambo), Frankurt (Matz) and Apenheul(Bongo)) to other Gorillas that for whatever reason haven't managed to contribute anything genetically to the population.

A look at Willard's excellent Geneological charts on Flickr or Gorillasland sites will give you an idea of how complex the genetics are nowadays.

 

Add to the fact that Stefi (Jambo's father) and Millie Christine (Colo's mother) are believed to have been siblings (captured from the same troop), therefore making their widespread genetic lines related to each. Who knows how many individuals are related within Europe/America....

 

Almost certainly they were, though given their extreme closeness in age they were probably half-siblings- same father, different mothers, though in wild groups the degree of relatedness may be a lot higher than is allowed in captivity so genetically they were probably very close indeed, perhaps nearer to full siblings. Certainly 'Colo' and her presumed 'uncle' 'Stefi' resembled each other facially.

 

According to a recent publication in IZY:

"The genetic health of the EEP population is excellent. There are 98 founders, with a reasonably equal representation. Around 81% of the founders have a representation of less than 1,5%. The population has a gene diversity of 98,5% and, proper management provided, the targeted gene diversity of 90% can be maintained for at least 199 years. The mean kinship value is currently 0,0148 and inbreeding is virtually absent. Recent research on gorilla genetics shows that genetic variability in captivity might be higher than genetic variability found in wild gorilla populations".

 

I am sure that is true. In the wild I imagine there is at least a measure of in-breeding within groups on a regular basis. It is never deliberately allowed in captivity and there are only a few examples in the European population.

From the above it sounds like imports from the US would be regarded as unnecessary.

 

Female 'Namoki' (9 years old) has moved from Bristol to Belfast.

 

Namoki already introduced to group.

Interesting little video on both Belfast's facebook page and the Gorilla specialist sites, showing 'Namoki' already in with male 'Gugas' and at least one female. Its dated Wednesday 15th so these intros must have occured very shortly after her arrival. She seems quite relaxed, and for a new arrival, pretty confident too.

 

After a brief correspondance with an EEP official I can confirm this.

Moreover, the official argued an exchange between the EEP and SSP won't be wise.
Quote: "As both populations of the EAZA and SSP are genetically very healthy, it is better to keep for the moment the bloodlines as much separate as possible. Then it will be easier to make exchanges in the future."
I asked, why is that? And the reply was, "If you still have a genetically healthy population with enough animals to make the necessary exchanges, it is better not to mix them. It will decrease your possiblitilies to exchange in the future unrelated animals (as they will all be related). Furthermore, exchanges with the USA are very difficult, much paperwork, and some zoos will keep the new male for 6 months alone in a sterile cage (has happened with bonobos) which is something we in Europe do not like very much. It is also expensive, so better not to do it."
I cannot understand that argument / point of view, and maybe someone here is able to help me out. For one thing, both the EEP and SSP are heavily mixing the bloodlines within their area already, using the full potential of their respective gene pool to ensure genetic diversity; which makes sense. So why not extending the pool across the Atlantic, allowing to choose from more potential matches for reproduction?
It can't be the costs and bureaucracy alone I think, as - for another thing - the EEP does make exchanges with Australia, Africa and Asia. (Alleged reason, quote: "They don't have a sustainable population and the populations were already mixed. They need the EEP to exchange animals.")
To put it this way, what would be the criteria for a "good moment" to start a transatlantic exchange in the future? An (unlikely) breakdown of the sustainability of one of the populations? Why - maybe - later but not now? And are we about to breed two new sub-subspecies, Gorilla g. g. Europeus vs. Americanus?
As long as I don't hear better arguments I'll stick to the assumption that it's pure ignorance between the two organisations that prevents exchange.

 

Its worth remembering that a few Gorillas have gone from Europe to the USA and vice versa, but they were mainly in the 70-80's era, pre EEP organisation of the population, and were the result of individually organised exchanges/deals between Zoos.

From memory;

m. Kisoro. Lincoln Park to Howletts UK(and later returned to US)
m. Mumbah. Howletts UK. to Columbus US.
m. Tatu. Jersey to Oklahoma US. exchanged for;
f. G.Anne. Oklahoma to Jersey- and later to Melbourne. Aus.
f. Linda & m (her young son)VIP- Wassenaar to Milwaukee US.(after Wassenaar closed)
m. Kakinga. Jersey to Calgary(Canada).

Kisoro has many descendants in the Howletts groups. There may be one or two others but I can't remember any, except of course the much earlier transfer of m. Stephi from Columbus to Basel. Incidentally, the reasons/explanations for not exchanging US and European animals at this time would seem to make reasonable sense to me, but they may still need to overcome this apparent reluctance at some time in the future.

 

I do not know all the reasons, but if you once would have had to arrange the paperwork for the transfer of a primate from Europe to the US, you would understand why zoos are reluctant to do these exchanges, unless it is really necessary for the populations. Considering all that I have read, it seems to be a complete waste of money and time to do such an exchange. It is like living in Austria and going to the UK to buy your shoes. If both subpopulations are healthy, and exchanges are possible without high levels of inbreeding, why the fuss? There is no risk for breeding two "subspecies" are there is no active selection, and both subpopulations have a huge numer of founders.

 

Really, if animal exchange intercontinental is going to be a success quite a number of countries and regional zoo organizations need to seriously look at their import / export procedures. The reason imports / exports do not happen too much between North America and Europe is borne out it the huge paperwork involved over on the Atlantic ...

 

Please don't shoot me for this question but here it goes surely if Gorillas are breeding well in captivity and their is a surplus of males in particular and I imagine there will get to a point of genetically linked females then would it not be responsible of zoos instead of castration attempt to re introduce some of these animals back into the wild which would in the long term help the wild population and diversify that gene pool

 

Is there a reason that Shinda (Kibabu x Frala) at Prague does not breed even though I believe she is the dominant female? Contraceptives?