[HN Gopher] After 120 years, Yellowstone bison are a single bree...
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After 120 years, Yellowstone bison are a single breeding population
Author : bikenaga
Score : 86 points
Date : 2025-03-05 16:04 UTC (6 hours ago)
(HTM) web link (phys.org)
(TXT) w3m dump (phys.org)
| y33t wrote:
| I saw a documentary (PBS? Ken Burns? Something like that) about
| bison and I'm astonished we have any left today. They had a
| couple of private herds and a handful of individuals in zoos, and
| that was just about it. That's after having a population, less
| than a century previous, that produced regular accounts of
| covering the land for as far as the eye could see. The only
| reason we didn't wipe them out completely was because of just a
| few people working independently of one another who thought it
| would be a shame to see them disappear.
| gooseus wrote:
| https://www.pbs.org/kenburns/the-american-buffalo
|
| Wonderful documentary.
| TomBombadildoze wrote:
| Buffalo also feature prominently in The West, another
| fantastic Ken Burns documentary.
|
| https://www.pbs.org/kenburns/the-west/
| karmakurtisaani wrote:
| Something similar also happened in Europe. They were eradicated
| everywhere but a small natural park in Poland. Now they are
| being reintroduced, although I don't know where they will find
| the space.
| linkregister wrote:
| European Bison?
| pjmlp wrote:
| Yep, https://en.m.wikipedia.org/wiki/European_bison
| sidewndr46 wrote:
| Somewhat curiously, there is another recently extinct animal
| the "Auroch" which was hunted to extinction as well. As
| recently as 1000 years ago they were quite plentiful, but
| completely extinct by the time Europeans started moving to
| the Americas
| WorkerBee28474 wrote:
| There have been some, let's say, 'interesting' attempts to
| recreate the species via back-breeding [0]. They seem to be
| having some success.
|
| [0] https://www.independent.co.uk/news/science/nazi-super-
| cows-e...
| dendrite9 wrote:
| Lions were also roaming Europe relatively recently, likely
| into the middle ages.
| bkovacev wrote:
| Fruska gora, a mountain region in Serbia, has acquired or
| were gifted 5 European bisons from Poland[0]. It's always
| heartwarming to see a country working extremely hard to
| preserve any species. It was devastating news for a lot of
| people that one of the bisons, Djuka, passed away recently
| (not to be confused with a Serbian politician Vladimir
| Djukanovic also known as bison Djuka[1]).
|
| [0] https://www.gov.pl/web/srbija/poljski-bizoni-u-
| nacionalnom-p...
|
| [1] https://en.wikipedia.org/wiki/Vladimir_Dukanovic
| writtenAnswer wrote:
| Makes sense. In Zoo tycoon, these fuckers kept breeding like no
| one's business.
| sidewndr46 wrote:
| It was a deliberate attempt to deprive Native Americans of
| their historical means of support. You can't besiege a Native
| American city because they had already been pushed off their
| historical lands. But if you can eliminate a major source of
| food for them, it's possibly even more effective.
|
| In general people under-estimate the capability of humanity to
| eradicate other forms of life. We've managed to eliminates
| organisms as plentiful as things like rinderpest for example.
| Large animals are actually easier. Were it not for a last
| minute change, almost all forms of whales would have been
| extinct in the 20th century. We've been the most advanced life
| form on Earth for a long time, possibly even before modern
| humans arrived. But in the past 1000 years or so we really
| became the most dominant life form. Our population has exploded
| and we can pretty much push out any other form of life we
| choose.
| snowwrestler wrote:
| Latest estimates I recall are that humans and our livestock
| together comprise over 90% of the total mass of land animals
| globally. All wild animals together are less than 10%.
|
| The mental picture of a wild Earth on which humans live is
| now outdated. The Earth has become a human place, with
| essentially some open-air zoos containing the few wild
| animals we have chosen to not kill.
| gus_massa wrote:
| xkcd 1338: Land Mammals
|
| https://xkcd.com/1338/
|
| https://explainxkcd.com/1338/
| 0xcafecafe wrote:
| Bacteria still outweigh us a thousand to one and that's
| not counting those already in our bodies is a great alt-
| text as well.
| mitthrowaway2 wrote:
| Bacteria aren't really animals though.
| Brybry wrote:
| Land insects/terrestrial arthropods might match that
|
| https://phys.org/news/2023-02-global-combined-weight-
| insects...
|
| https://pmc.ncbi.nlm.nih.gov/articles/PMC9897674/
| lalalandland wrote:
| Insects comprise a total weight to about 1 billion tons.(1)
| Which is roughly the same as the weight of all people and
| farm animals on Earth combined. (1)
| https://www.jpost.com/environment-and-climate-
| change/article...
| buerkle wrote:
| https://en.wikipedia.org/wiki/Rocky_Mountain_locust is an
| interesting example of eradicating an organism. From massive
| swarms of locusts to none in under 30 years.
| fanatic2pope wrote:
| Along the same lines is the passenger pigeon.
|
| https://en.wikipedia.org/wiki/Passenger_pigeon
| cyberax wrote:
| > It was a deliberate attempt to deprive Native Americans of
| their historical means of support.
|
| No, it was not. The bison population collapse was not
| something expected or planned. One year the bison simply
| disappeared (1882).
|
| The bison ecosystem in North America was deeply unnatural.
| Bison are fast-replicating herbivores that don't have any
| natural predators! This only happened because Natives
| exterminated almost all the large predators.
|
| Such systems almost always go through boom-bust cycles, and
| that's exactly what happened. The migration patterns were
| disturbed by railroads, and that likely led to the spread of
| the Texas tick fever and anthrax among the bison population.
| They have around 90% death rate, and that's what caused the
| population collapse.
|
| However, this time the population did not recover by itself.
|
| > But if you can eliminate a major source of food for them,
| it's possibly even more effective.
|
| It's the same nonsense as giving smallpox-impregnated
| blankets used to exterminate populations.
| onychomys wrote:
| Do you have any evidence for the claim that it was disease
| rather than the immense slaughter?
| cyberax wrote:
| Yes. There are multiple papers written about this, here's
| a nice overview article: https://www.nacdnet.org/wp-
| content/uploads/2019/04/bisoncoll...
|
| There was overhunting of bison, but normally overhunting
| leads to a gradual decline of the population (and we've
| seen that with overfishing). The bison near-extinction
| happened within _one_ year. The hunters in 1883 were
| waiting in vain for the bison to come.
| sidewndr46 wrote:
| from page 108:
|
| Removing 840,000 animals from 4.5 million leaves them a
| good 3 million short of extinct. But Texas tick fever has
| an 81% death rate.11 Removing 81% from 4.5 million leaves
| just 855,000. Shooting b 840,000 of them leaves N 15,000,
| which is a lot like b 25,177 (Fig. 1)
|
| Their own conclusions was that absent hunting, there
| would have been around 855,000 bison that year. Hunting
| reduced the remaining population after tick fever by
| 99.2%! Ignoring this is the equivalent of suggesting it
| was not an iceberg that sunk the titanic, but a lack of
| buoyancy.
| SpicyUme wrote:
| Grizzly bears hunted bison and were present in the plains
| states down through Texas and into Mexico. The last Grizzly
| in Arizona was killed later than the last one in
| California.
| cyberax wrote:
| Grizzly bears do not normally hunt healthy adult bison.
| They will normally hunt weakened or injured individuals,
| or bison calves.
|
| In general, predators need to be overwhelmingly more
| powerful than their prey (or use pack tactics, like
| lions).
| Miraste wrote:
| This is true of macro life forms, but rinderpest is a bad
| example. It's one of only two diseases we have ever been able
| to eliminate. Both of them were viruses-we've never stopped a
| bacterial disease, and with the increasing failure of
| antibiotics, that's only going to get worse.
| openasocket wrote:
| There are several examples of this in other species. The
| Przewalski horse is probably one of the most dramatic examples.
| The population was reduced to around a dozen individuals, all
| in captivity. After an intensive breeding and reintroduction
| program, the population is now around 2,000, with several
| hundred of those in the wild. There's also the Pere David's
| deer. It's an interesting species: the only semi-aquatic deer
| species. It has webbing between its hooves and eats aquativ
| plants (along with grass). They were hunted essentially to
| extinction in their native territory in China, the only
| remaining individuals were a handful taken by missionaries
| (including Pere David, their namesake). Today their population
| is over 8,000, with hundreds reintroduced to the wild.
|
| It's sad to think about, but it's also hopeful in a way.
| Humanity as a whole nearly killed these species, but a few
| dedicated individuals were able to save them.
| david38 wrote:
| This is not true. An officer from the US was sent to protect
| the Yellowstone herd at some point. IIRC he had previously been
| assigned to fight Indians and had a track record for
| "effectiveness" aka modern day war crimes. Apparently this was
| more a personality trait than particular hatred of the tribes
| of the plains because when he was ordered to protect the bison,
| he did it with the same energy and "effectiveness".
|
| Not claiming he was the only one, but possibly the only one
| with enough guns, soldiers T his command, the backing of an
| executive order, and a dim enough view of human life to move
| the needle as much as he did.
|
| I need to go research this again and erase this comment if I'm
| talking trash or update it if I'm not.
| kapitanjakc wrote:
| Isn't interbreeding bad for their health?
|
| Genuine question.
|
| Is it interbreeding in a way like all bisons present now are
| sharing the ancestors or is it like it's all a single family of
| 6k bisons now ?
| ch4s3 wrote:
| Having a single breeding population across the park creates
| more genetic diversity than would be present in isolated herds.
| thrance wrote:
| > Bison like those in Yellowstone once suffered a population
| crisis that conservationists call the "population bottleneck"
| of the 19th century. By the early 1900s, American bison numbers
| had been reduced by 99.9% across North America and only 23 wild
| bison were known to have survived poaching in Yellowstone.
|
| So at their worst this particular population only had 23
| individuals left. Interbreeding is bad insofar as it increases
| the chances of passing harmful recessive genes to younger
| generations.
| diggan wrote:
| Compared to the alternative of the species not surviving at
| all, it seems like the better option :)
|
| Besides, it seems like they think it's genetically healthy, so
| doesn't seem like a problem. I'm assuming they've verified this
| somehow.
|
| > Today, the Texas A&M researchers report that the Yellowstone
| bison population appears to be functioning as a single and
| genetically healthy population that fluctuates between 4,000
| and 6,000 individuals.
| casenmgreen wrote:
| Getting that "living on top of a volcano" risk feeling :-)
| nonethewiser wrote:
| > Compared to the alternative of the species not surviving at
| all
|
| How about compared to two distinct herds?
| pinkmuffinere wrote:
| Biology is not my area of expertise, but: Interbreeding is bad
| when it's a small population interbreeding for a long long
| time. From the article it sounds like they aren't worried about
| the genetic diversity of this 6k bison herd. I'm sure it would
| be better to have more diversity, but that's hard to achieve
| with animals brought back from near-extinction.
| darth_avocado wrote:
| There are a lot of private herds. But a lot of them have been
| bred with domesticated cattle and do not have the pure bison
| DNA in them. They can be used as a last resort. The solution
| here would be to slowly start separating herds to more
| locations away from Yellowstone. Over generations, the
| genetic makeup will separate enough to be considered separate
| populations.
| InitialLastName wrote:
| The notable discovery is that, where the evidence a few decades
| ago was that the bison were breeding in their historical herds
| (so multiple, smaller genetic pools), they now appear to be
| breeding between herds (so a single larger, more diverse
| genetic pool).
|
| AIUI with small populations, more variation in breeding between
| groups is a good thing, because it spreads genetic diversity
| across the whole population.
| Sharlin wrote:
| You probably mean _in_ breeding. _Inter_ breeding is good. It
| is _good_ that the bison herds mingle and interbreed.
|
| Anyway, for mammals an initial population of a couple dozen
| individuals (assuming they're reasonably genetically diverse in
| the first place) is plenty enough to produce a population of
| any size without problems.
| onychomys wrote:
| There's a general guideline called the 50-500 rule. You need
| at least 50 animals to avoid immediate inbreeding (and also
| stochastic extinction from a fire or flood or disease etc),
| and about 500 to have a genetically healthy population. That
| varies some after a bottleneck event since your genetic
| population will be functionally less than your actual
| physical one, but it's a decent way to approach the problem.
| gavindean90 wrote:
| At least two groups are now breeding as a single population.
| The genetic diversity might be more spread out over the
| population. As I understand the article there were two
| functionally separate groups as late as 20 years ago (already
| 100 years after the introduction of the Texas bison to the
| original Montana heard) and now they are recorded as being a
| single population.
| kaikai wrote:
| I have mixed feelings about this news, because while it's good to
| have more genetic diversity, it makes it easier to justify
| culling animals. Having multiple herds with distinct breeding
| populations means each herd is more likely to get protected.
|
| The us government culls bison from the Yellowstone herd every
| year, to discourage them from leaving them park and competing
| with cattle grazing on public lands.
|
| Bison are managed completely differently than other wildlife in
| the area like moose and elk, because they compete with cattle.
| They're forced to stay inside the higher elevation park
| boundaries, even when the snow is too high for them to forage
| effectively. They get hazed by helicopters, chased by DOL agents
| and rangers on horseback, and forced to run miles through snow to
| cross that invisible line back in Yellowstone. I've seen newborn
| bison calves with broken legs from getting hazed back into the
| park.
|
| If they were allowed to migrate seasonally and breed normally,
| they would have a much larger range and population.
|
| Source: I used to live on the park boundary and was part of a
| group documenting bison management.
| _DeadFred_ wrote:
| Does the land they keep the bison from going to happen to be
| federal land the cattle farmers lease? Since you say DOL agents
| it sounds like. So lame. Prioritizing private ranchers on the
| peoples' land.
| kaikai wrote:
| It's a mix of federal, state, and private land. There was a
| group of private landowners that fought for years to keep the
| DOL from hazing bison off of their PRIVATELY owned land on
| Horsehead Butte.
|
| And yes, that's the Department of Livestock. There's an
| interagency management group that handles bison in the area,
| including the Department of Livestock and at times Homeland
| Security. They also run catch pens near Gardiner, where they
| round up wild bison and send them to slaughter houses.
| onychomys wrote:
| There's actually LESS genetic diversity in a single breeding
| population than in two separate ones. When you have two, they
| can drift in different directions or be subject to different
| selection pressures. With just one, all of that stuff is
| swamped out.
| FuriouslyAdrift wrote:
| There's also a herd at Custer National Park comprised of 2
| breeds ("Minneconjou" and "Humbolt")
| pmdulaney wrote:
| There are some bison on Catalina Island. Maybe they should swap
| some animals.
| kaikai wrote:
| The Catalina bison (like many bison in other places) have
| interbred with cattle. They're not purely bison anymore.
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