Monday 3 February 2014

Donate for the Wisents in the Caucasus!

In this post I suggested that the over-purity of the Wisent and its two bloodlines might be a serious threat for the survival of the global population. The wisents in the Caucasus mountains are condemned by many people in conservation because they have introgression from the American bison, what also shows in their phenotype to a certain extent. The action plan of the Mammal research institute at the Polish academy of sciences [1] even proposes the culling of all the Wisents in the Caucasus. I think this would be a terrible loss. One of the reasons why this herd is rejected by so many conservationists is, except that they are not "pure", that they influence the vegetation of their environment by grazing and damaging trees. So what is regarded as desired in pure Wisents in grazing projects is used as an argument to kill off the Caucasus population. The behaviour of destroying trees by peeling off bark is not a legacy of their few American ancestors, but displayed by Wisents as well [2,3]. Even free-ranging cattle occasionally push down young trees [3]. 




The Caucasus population is very likely the genetically most diverse population worldwide thanks to the intermixture with A. bison followed by absorptive breeding; as outlined in the post above, the high inbreeding of the two "pure" bloodlines has severe effects on some populations, including drastically lowered resistance against certain diseases [1]. It is likely that these problems are less severe in the Caucasus population, maybe even to a considerable extent. Unfortunately no study on that has been carried out yet, probably because of the a priori lack of interest for this herd. Furthermore, the Caucasus population is the only Wisent herd today that has been living in the wild for the last 70 years, so it probably were always the healthier and hardier animals that survived and reproduced, and if there were disadvantageous features inherited from the American bison they probably disappeared. So to me, the Caucasus population is worth to be preserved, protected and also expanded - but this expansion should happen by further mixture with "pure" wisents, or, if their number increased sufficiently, selective culling of those wisents with optical features of their american relatives. There is a neighboring herd of LC-wisents and I think both populations should be merged together. 

In the 1980s, the Caucasus herd was the only large and vital population of the wisent since the 19th century counting incredible 2.300 animals [1]. Poaching dramatically reduced them down to about 200 animals. Not only this itself is a shame, but also that the disinterest of conservation on this population might have been one of the reasons why poaching had such a severe effect. Thankfully, the Naturschutzbund Deutschland (NABU) in cooperation with Russian conservation groups now protects this herd by supplementary feeding and rangers. If you want to support their efforts to conserve the most genetically diverse and vital and sadly most underrated wisent population in the world, go to this website and scroll down where you can donate for this project

This plea is not only for the Caucasus herd. There are about 700 Wisents which are excluded of the breeding book and therefore "not existing" just because they have no documented genealogy - this does not necessarily mean they have hybrid ancestors, it is also possible that some of them are "pure" wisents that even represent bloodlines of the 12 ancestral animals that are now lost in the gene pool formed by the animals of the breeding book. And even if those animals have bison or cattle hybrids in their ancestry, I do not see that as a reason to exclude them from conservation completely. As you might know, a large number of American bison are genetically influenced by domestic cattle. Although the American bison has a large, genetically diverse global population, seemingly nobody had the idea to start a similar pedigree cult in this species, although it probably would not cause severe inbreeding problems, contrary to the case of the Wisent. And as a side note, there is almost no optical indication of a hybrid ancestry in many of those bisons, so why should that be the case in the wisent if the breeding with such animals is carried out carefully? 

So my proposal for reducing the threat of the Wisent failing repopulating the wild because of a lack of genetic diversity is: 

  • Opening the lowland line for introgression of the lowland-caucasian line and closing the latter from introgression, until the inbreeding coefficient is equal in both; after that, both lines should be merged together
  • creating another blood line group that consists of the wisents without proven "pedigree", also intermixed with animals from the "pure" bloodlines

Of course "pure" Wisents should be preserved and at least one closed gene pool should consist of these animals exclusively (I see no point in separating the LC and L line because of the little differences between the former two subspecies). But what if many of them are deformed, infertile or prone to diseases and parasites so that no viable population below 100 individuals can be set up? I think that genetically diverse populations consisting of the blood group I propose above are necessary for creating more vital wild wisent populations. 

Literature 


[1] Mammal Research Institute, Polish Academy of Science: European Bison Bison bonasus: Current state of the species and an action plan for its conservation. 2002
[2] http://www.derwesten.de/staedte/nachrichten-aus-meschede-eslohe-bestwig-und-schmallenberg/waldbesitzer-aergern-sich-ueber-wisent-schaeden-id8568518.html [German]
[3] Bunzel-Drüke, Finck, Kämmer, Luick, Reisinger, Riecken, Riedl, Scharf & Zimball: Wilde Weiden: Praxisleitfaden für Ganzjahresbeweidung in Naturschutz und Landschaftsentwicklung. Arbeitsgemeinschaft Biologischer Umweltschutz

16 comments:

  1. http://whiteelkranch.com/live_sales.htm
    http://www.bisoncentral.com/bison-trading-board/european-bison-wisent-sale
    The American population of European Bison are for sale incidentally. I bet they aren't in the herd book.

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  2. I just found an online article, that there is s new project to breed back aurochsen. The project is called "Uruz Project" on "True Nature Foundation". Have you heard of it?

    Here is the link to the article: http://www.echo-online.de/region/bergstrasse/lorsch/Vereinsziel-Die-Rueckkehr-des-Auerochsen;art1247,4555575

    Could you say something about this project?

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    1. Yes, I knew the project already before it was officially released because it was initiated by Henri Kerkdijk-Otten - the name even was my idea, lol. I decided not to write much on that project until they really have something to grasp on, since it is a kind of "Tauros 2.0". If something interesting starts to build up, I'll keep you on track for sure.

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  3. Hello all,
    Nice article once again, thanks.
    This subject is matter for quite some emotional issues and the scientific community is not immune to it nor to dogmatic ideas. But the truth is that in some species or subspecies recovery, some times scientists have no other option than add genetic influx from close related breeds, this has been proposed to the Florida panther that is one very good example of it.
    Cheers!

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    1. Absolutely, and the use of introgression of related species becomes even more justified when considering that a number of mammal species actually already have experienced documented genetic influx from other species; not only the bison, but also the Milu from Red deer, wolves and coyotes from domestic dogs, wild boars from domestic pigs, plus a few others. Hybridization is a part of evolution, especially in the case of the Wisent which actually may be a hybrid species, I actually wanted to mention that in that post, but I didn't have the time to pick all the references together.

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  4. For the first time I strongly disagree with you. I consider your proposal of A. Bison introgression in Wisents stocks not a good idea. You want to artificially hybridize two different species that lives in two different continents with a different "recent phylogentic history". Probably the most wise thing to do is to merge the two wisent lines after a clear genetic study mixing the animals that show the higher genetic differences. Please, do not consider me a "hyper-conservative ecologist", one of those people that consider any single isolated population or subspecies, also those fragmented because of man, as a separate and unique entity.F.e. in Italy the conservationist do not want to create new populations of the Mesola deer, the last completely autochtonous Italian deer that live actually all in a small forest in Romagna and suffer from inbreeding depression, near other red deer populations because they fear they could naturally crossbreed with other deers that derive from reintroductions or from animals that cross the state boundaries from France, Switzerland Austria or Slovenia! By the way the same people are happy that the Apenninic wolves are meeting Balkan and Carpathian wolves in Alpine lands!!!!!! Hybridization is one of the evolutionary forces (especially in plants) but it have to occur naturally or it should be the extrema-ratio in conservation. Yes, this suject has a lot of aspects, also controversial: f.e. is it right to kill Oxyura jamicensis that live and nest in Central Europe and UK because it hybridize with the autochtonous endangered Oxyura leucocephala that is endangered , critically endangered in Europe, and nest in Europe in few locations in Iberia??? I think in that case no..because ok it was stupid to free Jamaican Ruddy Ducks in Europe...but now is the same stupid to eradicate thousands animals (and I think it's not feasible completely) that are deeply naturalized and that hybridize occasionally with White headed ruddy duck, with fertile offsprings naturally!!! It's an expensive, probably not concludent, unethical project...but I'm driving completely off topic as usual!! Sorry I'm one of those people that can't reason without examples!!

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  5. Sorry probably it was not so clear in my comment, I obviously disagree with "Hyper-conservative ecologist" and their approach as in Mesola deer case!!!! Populations of animals, but also of plants, are something highly dynamic :some ecologists sometimes forget it!!

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    1. I have nothing to say against that, because I think this is a matter of opinion. But if it is kept attention that only male bison contribute to the wisent, their "cattle mitochondria" won't get reduced and the low Y diversity is supplemented as well. I think this article on the mortalities/diseases in the herd that was released in Bulgaria supports my view that "pure" wisents will have quite some problems in reconquering the wild because of their inbreeding depression:
      http://www.rewildingeurope.com/blog/bison-in-the-bulgarian-rhodope-mountains-ups-and-downs/

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    2. Hello

      The mix of the 2 lines (lowland (LB) and lowland-caucasian(LC) line) already exists in the LC line itself ! In several breeding centers the two lines have been mixed. (Look at the European Bison Pedigree Book over the last decades...

      One of the reason why Polish scientists want to keep the lowland line separatly is because there is less side effects of inbreeding in this line.
      (the only caucasian male and maybe females of the LC lines had probably recessive genes...)
      The other problem is the over contribution of two founders in the lowland line and now in the LC line after mixing both lines ..
      So the solution is to lower the contribution of these 2 individuals.(Male n°45 and Female N°42)

      There are 3 Males Y chromosomes left today in the LC line and 1 in the LB line.
      The N°45 is the most common in both lines.
      Breeding centers in germany (Hardehausen, Springe, Hanau... have done a really good job in the last years to breed very rare males with N°100 et N°15 Y chromosomes and spread them in lots of places.
      So there is a good opportunity to improve genetic diversity in the LC line that includes all the genetic material of pure wisent living in the World today.

      So why not keep the two lines separate and see the evolution of the LB line in the future.

      Concerning the montanus hybrids, theses animals have been well adapted to their habitat with very good reproduction rate before poaching dramaticaly reduce this population.
      For sure they could be a good way to get some genetic diversity for wisents..if serious inbreeding issues continue.
      And if this population stay in the caucasus there is no threat for the other wild herds in europe !!

      Regards

      (Thank you for the really good work done on this blog)



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    3. Hello all.
      Filippo I do understand your concerns regarding mixing different gene pools with no care and no rigorous work and study regarding the pro's and con's of such an action. However I don't believe our fellow Blog host it's advocating such an action without the proper care (actually none of us I believe), the issue is that the macro species Bison in all regional variations was so depleted by Human action that one must consider such type of action in order to benefit and save the whole species as best as possible with what is available.
      In my humble opinion the Caucasus population is interesting at least to compare to the other populations and observe it's own evolution.

      The concept of what is a species from the scientifically point of view is in most cases strongly artificial to say the least if not unnatural. From the practical point of view no type of Bison discriminates others and they're different aspects only represent the plasticity of an organism to different demands and to the recent evolutionary history.

      Regarding what you mentioned about the 2 separate continents, that is also in my view a very artificial concept and that division is extremely recent so recent that many species of land animals and plant species exist in both sides in a continuum.
      Wasn't the Bison group also a continuous population until quite recently from Iberia to Atlantic America? like the Elk/Moose? the Wolf? the red Fox? the Wapiti deer/Elk? and many others?

      Best regards to all.

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    4. Hi Vince B,
      of course I am aware of the influx from the L line to the LC line, and I think this makes the problem even worse because it reduces the diversity even further because it diminishes the caucasian influence. That's why I suggested that the situation should be turned, and the LC line should get "closed" and the L line "opened" for getting introgression from the other line. Or at least merging both together. I know that breeders now breed under consideration of which founder individuals are underrepresented and which are overrepresented, but I am sure that the Caucasian bull is the most underrepresented of all, although it would be the most desired one because of the diversity it adds.

      I think the evolution of "pure" L line representatives might be that they die out or are virtually incapable of building up wild populations - the article on Rewilding Europe I recently found and posted above, which sadly confirms this concern.

      I really hope that finally the majority of the conservationists recognize the value of the caucasus population, so that they get protected and spread, and not killed off as those *excuse me* mad pedigree fanatics proposed.

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    5. Oh, sorry Vince B, I got you wrong regarding the influx from L to LC, I now understand what you meant, so I agree with you. Increasing the quantity by adding L animals and breeding in a way that underrepresented animals are better represented in the population is another good way to reduce the diversity problem.

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  6. http://www1.umn.edu/news/news-releases/2013/UR_CONTENT_456441.html

    To add more to the topic created by Tobi. The Uruz project seems to mainly differ from the TaurOs Programme by using fewer breeds of cattle close to Auroch in the hopes of producing a quicker Auroch like animal. Then use genome editing to get even closer to Auroch as researchers at the University of Minnesota have recently used to edit Holstein cattle with the polled trait from Angus. Though the first move from the Uruz project posted on the True Nature Foundation's Facebook feed seems to have been to buy some primitive Chianina cattle which sounds like a breed that would slow things down to me. Supposedly they have a strategy though to get an acceptable visual result in only 2 generations of breeding. Then I guess presumably they might start the genome editing once they have a visually good bred back population. I wonder why they don’t just pick one primitive breed that is already fairly close and then start the genome editing immediately. Do they hope to cut down on the amount of genome editing needed or do they hope that by waiting, the technology will improve and allow for faster results?

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    1. We should wait what they really are going to do. Advertisement texts are one thing, what is really done is another aspect. Picking the most primitive breed (like Lidia, for example) and editing this one indeed might be the most effective strategy, but the I know that at least the initiator of the project is biased against the fighting bull (not wise IMO) and who knows if it is really feasible in the way they imagine it. We'll have to wait.
      Chianina actually does not slow things down as far as I see that, they just have two undesirable dilution genes and short horns (which sometimes have a very good curvature), but their tight-muscled, long-legged and large body is in fact very useful, and there are only very few breeds that contribute this all at once. It was actually me who convinced Henri Kerkdijk-Otten of using Chianina, before that he was averse to Chianina as well.

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  7. https://www.facebook.com/truenaturefoundation/posts/1472482199631137

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  8. Regarding the two seperate lines. I think that both lines should be closed at this point and rebalanced in breeding centres for founder representation. There are only three female and one male lines still active in the Lowland line and so the female lines need to be urgently rebalanced to the point of using sex selection AI on the rarer mitochondrial lines and even selecting breeding bulls descended from one of the lesser represented lines to overhaul the balance.

    In the Caucasian Lowland hybrid line there are more known lineages and rebalancing should begin if possible. The ideal would be to get half the males descended from the Caucasian line and the other two extant y-dna lineages averaging around 25%. Then trying to balance out the female lines would be important again.

    Regarding the Highland Wisent. If that line is isolated and the population does not breed into the Lowland or Caucasian Lowland lines then leave them alone as they have adapted to their region and serve a purpose. If the hybridised American bison has infiltrated the full Caucasian Lowland population then merging of the Lowland and Caucasian Lowland becomes impossible due to dragging all populations towards the American Bison and Cattle populations.

    The difference between the Lowland Wisent and the Caucasian Wisent were smaller than either to the American Bison due to proximity of breeding regions and closer generational seperation. With only one Caucasian Wisent left there was no choice to breed to a Lowline Wisent. The American Bison is a different species not a different subspecies. The Lowland, Carpathian and Caucasian Wisents were different subspecies.

    As a point if there is no influence of the American Bison in the Caucasian Lowland line then the lineages extant that are not found in the Lowland Population and not descended from a direct Caucasian bull lineage for a long time, or with low genetic showing of the Caucasian line, should be considered, if healthy for reintroduction to the Lowland line. Allowing this small cross over without over saturating the Caucasian Lowland line any more and actively selecting for the Caucasian Lowland line to have a dominant number of bulls descended from the Caucasian Bull would help rebalance both populations. Once the selected individuals have been swapped both lines can be closed for rebalancing and genetic drift should take both populations away from each other again.

    It does concern me that there is no overall plan now that DNA can be tested. I did see an article which stated that the plan was more habitat, let the full bloods get on with breeding.

    Oh an regarding the studbook, the Nebraskan ranch selling Wisent is not mentioned in the herd book. The herd books are all available up to 2013 for digital download. In the most recent forward they state that any Wisent sent out to breeding centres will be considered lost if the breeders stop responding and the breeder stricken from the book. This is what happened to a French based breeder in the last book. Apparently after receiving the Wisent the owner ceased correspondence regarding necessary information regarding survival and breeding of the animals. Perhaps earlier publications may mention the ranch or perhaps they simply purchased unregistered animals.

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