Legally Carried Handguns Stop Two Brown Bear Attacks in Slovakia

Slovakia and the Czeck Repblic and several other central European countries now have "shall issue" handgun permit systems, or very close to them as "may issue".

The two most recent incidents where people used legal handguns to stop the bear attack happened a little to the south of the dark green bordered area.

Try that again.

The two recent incidents happened just South of the dark green circled area on the map.

I had no idea U. arctos is found in Europe. One wonders which way that migration across the Bering land bridge went.

ChatGPT:

How big is the geographic difference?
At the broadest level, adult brown bears range from relatively small bears in resource-poor populations to enormous coastal bears. The biggest populations occur where food is exceptionally abundant, especially along productive salmon rivers and coasts.
A useful rough picture for adult body mass is:

Population/environment Adult males Adult females
Small Eurasian / northern or interior populations ~100–200 kg ~60–130 kg
Typical North American interior grizzlies ~180–300 kg ~100–180 kg
Large Alaskan/Yukon grizzlies ~250–400+ kg ~150–250+ kg
Exceptional coastal Alaska/Kodiak bears 400–600+ kg possible 200–350+ kg possible

These are broad ranges rather than standardized population averages; age, season, sex, reproductive status, and whether the animal has recently fed heavily can shift an individual substantially.
The really striking part: Alaska alone
The geographic variation isn’t just a difference between Europe and North America. Brown bears differ markedly from one Alaskan region to another. A study of 11,651 Alaska brown bears found region- and sex-specific growth patterns, with large differences in asymptotic size among regions. The researchers associated much of this variation with habitat quality, particularly salmon availability.
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DOI
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Another Alaskan study comparing four ecosystems found that bears living where salmon were abundant were generally larger. Among adults within populations, lean mass itself varied enormously: approximately twofold among females and three- to fourfold among males.
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Wiley Online Library
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So two adult male brown bears from the same general part of Alaska can differ dramatically, let alone bears from opposite ends of the species’ range.

Why does this happen?
Food is probably the biggest driver. Brown bears are extraordinarily adaptable omnivores. Where they have access to huge seasonal pulses of high-energy food—salmon, spawning fish, carrion, berries, nuts, etc.—they can accumulate enormous fat and muscle reserves.
Conversely, bears in colder, less productive or food-limited environments tend to be smaller. Studies of Alberta grizzlies, for example, found that regional productivity and environmental conditions during both early life and adulthood affected body size.
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PubMed Central (PMC)

Climate and latitude matter, but latitude alone doesn’t predict brown-bear size particularly well. European populations illustrate this nicely: researchers comparing 1,771 bears from northern and southern Europe tested several competing explanations for geographic differences in mass rather than simply assuming that northern bears must be larger.
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PubMed

And then there are the giants
The famous Kodiak brown bears and the enormous coastal bears of Alaska and British Columbia aren’t a different species. They’re Ursus arctos populations living in environments where food availability permits exceptionally large body sizes.
This produces a somewhat counterintuitive situation:

A “grizzly bear” can be a ~150-kg adult male in one population and a 400+ kg adult male in another, while both are Ursus arctos.
And individual variation within a population can itself be huge. In fact, the scientific literature emphasizes that brown-bear body size is highly plastic and that ecological conditions can produce substantial differences even among neighboring populations.
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One other interesting consequence is that males become disproportionately larger in the biggest populations. The Alaska study found that sexual size dimorphism increased with asymptotic body size, meaning that exceptionally food-rich environments don’t simply make both sexes larger by exactly the same amount.
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DOI

So Kodiak Alaskan compared to Slovakian bears of the same species are 4 to 5 times BIGGER.

Because in America, Bigger is Better. Just go to Walmart.

We just spent several days in Vienna, 175 miles SW of that spot. Didn’t seen any bears there. We went hiking on the Patscherkofel near Innsbruck and no bears there, either. But it was a crowded, sunny Sunday.

Don’t give the bears any ideas...

I wasn’t familiar with the range in sizes. Thanks. Wolves do the same epigenetic thing.

In California bears got big because of yet another factor: They didn’t need to hibernate here. That changed everything, especially the distribution of food once Indians figured out not to grow acorns immediately adjacent to their habitations.

BTW, if you haven't read it... this will blow your mind.

The fossil record appears to be pretty clear. From Europe into Siberia, then across Beringia (now separated by the Bering straights, then after the last glaciation, down into Canada then the lower 48. Ursus Arctos is a latecomer to North America south of Canada. Probably sometime about 13K to 10K years ago. People were already here.

Ursus Arctos probably helped with the mass extinction of mega fauna.

The fossil record appears to be pretty clear.

The mtDNA data were not so clear back when I was researching that information.

Ursus Arctos is a latecomer to North America.

When I ran those queries this morning in response to this thread the Brave AI answer was a very interesting discussion. I'm posting this for you, as I suspect you'd read it.

ME: Is it suspected that the later successful invasions of bears and wolves is because the short faced bear and dire wolf were no more?

Brave: It's a reasonable hypothesis and it's been proposed, but the evidence points to a more nuanced picture — it's less "the natives cleared out, then the invaders moved in" and more both groups responding to the same environmental collapse, with the invaders being more adaptable.

Bears: The competition hypothesis is real but contested. Steffen & Fulton (2018) found co-occurring Arctodus simus and Ursus arctos remains at Pellucidar Cave, Vancouver Island, and proposed territorial niche partitioning and competition as a factor. However, their own conclusion was that post-glacial shifts in food availability and vegetation quality were probably the primary driver of Arctodus's decline, not direct competition with brown bears. The Wikipedia summary of the literature captures it well: "multiple studies put doubt on brown bears being culpable in A. simus' extinction, with the brown bear being more of an ecological replacement that was more adaptable to change." In Beringia specifically, Arctodus went extinct locally ~23,000 BP (possibly due to Heinrich Event-2 cooling) before brown bears re-emerged there ~23,000 BP — so the timing actually supports the "replacement" framing over the "competitive exclusion" framing.

Wolves: The case is weaker still. The dire wolf (Canis dirus) was largely absent north of ~42°N, while the Beringian wolf occupied that northern zone — so they were geographically complementary rather than directly competing. The dire wolf's extinction is attributed primarily to loss of megafaunal prey (mammoths, horses, camels) and the broader ecological collapse, not to displacement by C. lupus. The Beringian wolf, which was a direct competitor, went extinct around the same time (~12,000 BP) as the dire wolf, and modern C. lupus expanded from Beringia ~25,000 BP — but the succession is better understood as the Beringian wolf lineage being replaced by the expanding C. lupus metapopulation, not as a simple "dire wolf left the door open."

Bottom line: The "released niche" idea has some support, especially for the bear case, but the dominant interpretation in the literature is that Arctodus and C. dirus were specialists dependent on megafauna and open-steppe conditions, while U. arctos and C. lupus were generalists better suited to the post-glacial world. The invaders didn't so much succeed because the natives were gone as they were the ones best equipped to survive the same transition that killed the natives.

ME: That's how I saw it. The western hemisphere late Pleistocene megafauna die-off came before the successful invasions.

Brave: Exactly. The sequence is well-established:

Megafaunal collapse (~13,000–12,000 BP) — loss of mammoths, horses, camels, Arctodus, C. dirus, etc. Expansion of generalists — modern C. lupus radiating out of Beringia (~25 ka, but really establishing in the post-collapse landscape), and U. arctos filling the ecological space left vacant.

The timing overlap means it's not a clean "extinction first, then invasion" — the generalists were already present and expanding as the specialists were collapsing. But the causal arrow is clear: the megafauna-dependent specialists went down, and the generalists that could survive without them took over. The invaders didn't need the niche to be empty to arrive; they needed it to be empty to dominate.

ME: Is there any sign of an irruption of herbivores in the transition?

Brave: Researched herbivore population shifts during the Pleistocene-Holocene transition

Short answer: no broad irruption at the large-herbivore level. The evidence actually points the other way — the vacated ecological space was largely just lost.

The most direct test comes from a 2022 PNAS study (DeSantis et al.) using body-size and isotopic data from the Edwards Plateau, Texas. They found "little evidence of compensation" — the surviving large herbivores (bison, deer, pronghorn) did not expand their isotopic niches or increase in body size to fill the space left by the extinct megaherbivores. The Holocene community was "strikingly truncated" with "missing pieces" across body-size and dietary niche space.

A 2023 Nature Communications paper on worldwide extant megafauna makes the same point explicitly: "although such events might have provided opportunities for population expansion in surviving species through compensatory dynamics, the observed decline of extant megafauna during this time indicates that such a scenario was never realised."

One notable exception: bison. A 2018 radiocarbon-based population reconstruction (Raupp et al., Nature Communications) shows Bison populations growing roughly exponentially from ~15 ka through the Clovis period and into the early Younger Dryas — a genuine boom. The 2023 Cambridge Prisms review also flags "a spike in abundance at the terminal Pleistocene and early Holocene" for bison, possibly reflecting competitive release. But this is a single taxon, not a community-wide irruption.

What did happen at lower trophic levels: the 2023 review notes that "the increased density of small-bodied mammals led in turn to sharp increases in the number of medium and small-sized predators" — so there was a bottom-up cascade through rodents and lagomorphs, but not through the large-herbivore tier where the megafauna used to be.

So the picture is: the megafauna-dependent specialists (dire wolf, short-faced bear) lost their prey base, the large generalist herbivores mostly just shrank (bison, elk, deer all underwent body-size diminution), and the ecological complexity was simply gone. The expanding wolves and bears weren't riding a herbivore boom — they were the ones best suited to a depleted system.

They found "little evidence of compensation" — the surviving large herbivores

ME: That's not what I was thinking. I was guessing that a die-off of herbivory came with possible comet impacts, the plants crashed, the herbivores crashed, then the predators went after them, then the plants came back, the herbivores irrupted, and the new predatores came in.

In other words, it's all about food.

Brave: Researched evidence for the Younger Dryas impact hypothesis and trophic cascades

Brave: Your cascade is the right shape — it is fundamentally a bottom-up, food-driven story — but the evidence shuffles the order a bit and the comet is the weakest link.

The comet: not accepted. The Younger Dryas Impact Hypothesis (Firestone et al. 2007) proposed exactly the trigger you're describing — an airburst igniting continent-scale wildfires, crashing the vegetation, and cascading down the food chain. But the "requiem" paper (Pinter et al. 2011) and subsequent critical reviews found the original "impact markers" non-reproducible or explainable by terrestrial sources. The mainstream explanation for the YD cooling is freshwater release from the Laurentide Ice Sheet disrupting the AMOC. That said, the Pilauco, Chile site does show a genuine charcoal spike at ~12,800 cal BP correlated with megafaunal disappearance, so some kind of biomass-burning event around that time is real — just its cause is debated.

The directionality is flipped in most records. Your model has plants crashing first, herbivores following. The paleobotanical evidence more often shows the reverse:

The Edwards Plateau study (Nature Communications, 2020) shows plant diversity dropped during YD cooling but recovered in the early Holocene, while large-mammal diversity did not. Plants bounced back; the animals didn't.

The Rancho La Brea state-shift paper (Science, 2023) shows a fire-driven transition from woodland to chaparral, but the trigger was human-ignited fires in an ecosystem already stressed by warming, drought, and declining herbivores — not a top-down vegetation crash.

The PNAS 2015 ecological state-shift synthesis (Dillon et al.) found that after megafaunal loss, vegetation generally showed release from grazing — increased woody plant density, not a crash. The plants grew, they didn't collapse.

So the better-supported sequence is: climate shift (YD cooling / aridification) → habitat change → herbivore decline → predator decline → (later) vegetation recovery → surviving herbivore expansion → generalist predators expand.

The "herbivore irruption" phase is real, but narrow. The bison boom (Raupp et al. 2018) is the clearest example — exponential population growth from ~15 ka into the early Holocene, consistent with competitive release once the megafauna were gone. But it's one taxon, not a community-wide pulse. The 2022 DeSantis study and the 2023 Nature Communications review both confirm that the broader large-herbivore community did not irrupt — it stayed "strikingly truncated."

Where your model is right: it is all about food. The bottom-up trophic cascade framework is well-supported in principle — the Sahul (Australia) network analysis (2021, Biological Reviews) explicitly showed that extinct species were disproportionately vulnerable to bottom-up cascades from plant community changes, and that herbivores were the trophic level most sensitive to vegetation shifts. The generalist predators (U. arctos, C. lupus) that expanded afterward were the ones best adapted to whatever the post-collapse food web looked like. The comet is the part that doesn't hold up; the rest of the cascade logic is sound.

ME: Ok, that makes some sense, in that the plant mix and character would have to adapt to invading humans using regular fire, just as they did to heavy herbivory in California after the invasion of bears and people. I have wondered if people drove the bison across the land bridge and wolves followed.

Brave: Evaluated the hypothesis that humans drove bison and wolves across Beringia

The "wolves followed bison" part is well-supported, but the "humans drove the bison" part runs into a serious timing problem.

The bison didn't get driven — they got shrubbed out. The key paper is Shapiro et al. (2004, Science), "Rise and Fall of the Beringian Steppe Bison." Using ancient DNA and Bayesian methods, they showed that Beringian bison genetic diversity began declining around 37,000 years ago, which correlates with the onset of the last glacial cycle and associated vegetation change. Critically, archaeological evidence does not support large human populations in eastern Beringia until more than 15,000 years later. So the bison were already in decline long before humans could have driven them. A 2021 PNAS paper on eastern Beringia reinforces this: shrub expansion preceded the megafauna turnover, and the authors note that "browsers increased in abundance with seemingly little influence by human hunting, despite the presence of their remains in archaeological sites."

The direction is also wrong for your model. The bison migration was west-to-east (Asia → North America), in two waves: the first ~195,000–135,000 years ago, the second ~45,000–21,000 years ago. The 2017 PNAS genomic study explicitly found "no evidence for the migration of North American bison back into Asia, which tentatively suggests unidirectionality in Pleistocene bison migration across the Bering Land Bridge." So there's no signal of bison being pushed back westward.

The wolf-follows-bison part is solid, though. The Beringian wolf's southward range extension into the continental U.S. (as far as Wyoming) is explicitly attributed to tracking prey: "The migration of the Beringian wolf southwards is assumed to have been the result of pursuing prey species," with steppe bison and muskox as the key drivers. So wolves did follow bison — but southward within North America, not across the land bridge, and the bison were moving on their own (following vegetation shifts and competitive release), not being herded by humans.

Where your model is closest to right: the 2016 PNAS bison phylogeography paper (Heintzman et al.) found that after the ice-free corridor opened ~13,400 cal BP, "people probably migrated from the south back up to the north through the ice-free corridor — so they're circling around the mountains — in pursuit of bison." So humans did track bison through the corridor, but as followers, not drivers. The bison were the ones setting the pace; the humans and wolves were both riding their distribution shifts.

Me: > So the bison were already in decline long before humans could have driven them.

Which bison? There was one native to the Americas that went with the megafauna die-off. I was half wondering if people drove the Eurasian flavor across the land bridge as a replacement food source given that the land bridge itself was effectively bereft of food. .

Clarified bison species taxonomy and migration history Good question — I was referring to Bison priscus (steppe bison) in Beringia, not the central North American population. The taxonomy matters a lot here, and it actually undercuts your replacement hypothesis:

There wasn't a separate "native" bison that got replaced. Bison priscus arrived in North America ~195,000–135,000 years ago, and evolved locally into the North American species:

B. priscus → Bison latifrons (long-horned bison, extinct ~20,000–30,000 ya)

B. priscus → Bison antiquus (ancient bison, the dominant large herbivore in midcontinent North America from ~18,000 to ~10,000 ya)

B. antiquus → Bison occidentalis (transitional) → Bison bison (modern American bison)

So the bison that survived the megafauna die-off — B. bison — is the direct descendant of B. antiquus, which was already in central North America. It's the same lineage that came in 195,000 years ago. No replacement invasion was needed.

What actually went extinct in Beringia was the B. priscus population that had stayed in the north (Alaska/Yukon). That population declined from ~37,000 ya (Shapiro et al. 2004) and was gone by ~10,000–14,000 ya. Meanwhile, the central North American descendants (B. antiquus → B. bison) were doing fine on the plains. So the "decline" I cited was the northern holdout population of the ancestral species, not a separate native species being wiped out.

On your "bereft land bridge" idea: the mammoth steppe was actually one of the most productive ecosystems on Earth — B. priscus was the dominant herbivore there, and Klondike gold mines have turned up more than 80% of fossil mammal bones as B. priscus. The land bridge wasn't food-poor; it was the core habitat of the steppe bison. What killed that population was the post-glacial shift from steppe to taiga/peatland, not a lack of food.

The "humans drove it across" part doesn't hold up for a simpler reason: B. priscus was already in North America 195,000–135,000 years ago, roughly 120,000+ years before humans arrived. There was no "Eurasian flavor" to drive — the bison had been evolving in North America for hundreds of thousands of years before the first human set foot on the continent.

Me: > There wasn't a separate "native" bison that got replaced. Bison priscus arrived in North America ~195,000–135,000 years ago, and evolved locally into the North American species:

That I knew.

> So the bison that survived the megafauna die-off — B. bison — is the direct descendant of B. antiquus,

That I didn't know. When was that established and with what degree of certainty? One would think it genetically gradual. What is the evidence for that?

> The land bridge wasn't food-poor; it was the core habitat of the steppe bison.

That I REALLY didn't know, as it goes directly against what I was reading 15 years ago.

The discontinuity in my thinking was that it was my understanding that all bison had died off in the late Pleistocene die-off. I then had to go looking for a replacement mechanism. Hence the hypothesis.

Brave: Researched bison genetics and mammoth steppe productivity

Two good questions, and they connect to the same theme: the bison story was being actively revised in the 2010s, so what you read in ~2011 was likely a snapshot mid-transition.

The B. antiquus → B. bison lineage: when and how certain

The evidence is mitochondrial DNA, and it's been building since 2004:

Shapiro et al. (2004, Science) — the foundational paper. Sequenced mtDNA from the oldest known North American bison fossils and showed B. priscus entered North America 195–135 kya, then radiated into B. latifrons, B. antiquus, and ultimately B. bison. This established the framework. The critical link comes from mtDNA of B. antiquus specimens dated to ~11,290–12,200 years ago, which sit at the base of Clade 1 — the same maternal lineage shared by modern plains bison (B. b. bison) and wood bison (B. b. athabascae). That's a direct nested relationship, not a sister-group or replacement signal.

The 2023 Scientific Reports paper (mitogenomes from the Northern Plains) confirmed that Holocene and modern bison form a clade distinct from B. priscus, with a common ancestor dating to 15,000–23,000 ya for populations south of 60°N. Degree of certainty: The mtDNA nesting is unambiguous — B. antiquus is not a separate species that went extinct while a different lineage took over. It's the same lineage, shrinking. The transition is indeed genetically gradual: body size diminished from ~12,500 to ~9,250 years ago amid warming and habitat change, with no genetic break. The caveat is that nuclear genome data from B. antiquus is still sparse — most of the phylogenetic resolution comes from mtDNA, which tracks only the maternal line. So the direction of descent is secure, but the full population-genomic picture (effective population sizes, admixture, selection) is still being filled in.

The mammoth steppe: why your 2011 reading was different

The "productive African-savanna-equivalent" framing is actually quite recent. The key paper is Zimov et al. (2012, Biological Reviews), "Mammoth steppe: A high-productivity phenomenon," which calculated from skeleton densities in Siberian permafrost that herbivore biomass reached ~10.5 tons/km² and plant productivity was comparable to temperate grasslands — not a barren tundra. That was a genuine paradigm shift. Before that, the mammoth steppe was understood as a cold grassland, but the "this was one of the most productive ecosystems on Earth" claim was new.

The 2021 PNAS paper on eastern Beringia (Zver et al.) reinforced it: the steppe-tundra was the dominant biome, bison were the most abundant large herbivore in interior Alaska, and the ecosystem's collapse was driven by shrub expansion (the keystone herbivores that kept the grasslands open — mammoths, horses, bison — went extinct, and the vegetation shifted from grassland to taiga/peatland). So the land bridge wasn't food-poor; it was the core habitat, and its conversion to shrubland is what killed the B. priscus population there.

Your 2011 reading was almost certainly from before Zimov et al. landed, or from a source that hadn't incorporated the "ecosystem engineers" framing. The bison-driven steppe maintenance concept (grazers preventing paludification, recycling nutrients, suppressing woody plants) really only became mainstream in the 2010s.

Me: I think people did in the mammoths. One gut shot with a short spear and the beast would be dead in three days from peritonitis. I've been a big fan of Zimov for a long time, but more in the sense that people have played a key role in abating successional vegetation by which to sustain a thinner snow blanket, one that currently captures geothermal heating to the detriment of the permafrost. IOW, it's not "global warming" that's melting the permafrost it is that people have abandoned those landscapes by which to protect and move herds of herbivores.

Verified mammoth hunting and Zimov's permafrost theories

Both points are well-supported, though they connect in a way that's worth making explicit.

The peritonitis mechanism is sound and increasingly well-evidenced. The 2024 experimental archaeology study (UC Berkeley, Nature Communications) showed that Clovis pikes, when thrust into a mammoth-sized target, functioned like hollow-point bullets — the wooden shaft split on impact, widening the wound and causing massive internal tissue damage. That's exactly the kind of gut wound that produces perforative peritonitis. And Eren's 2022 Science News-reviewed work explicitly describes the hunting strategy: target unprotected torso areas, follow the wounded animal until it dies — which is the peritonitis/bleeding-out scenario you're describing. The Zhenya mammoth (Pitulko et al. 2016, Science) is the direct fossil evidence: multiple spear/pike wounds to ribs and shoulder, a coordinated kill. Three days for a 6-ton animal to go down from peritonitis is medically plausible — untreated perforative peritonitis in large animals runs to death in 48–72 hours from septic collapse.

The Zimov permafrost argument is his core thesis, and it's getting field data behind it. The mechanism chain is:

Megafauna grazing → open grassland → compacted, thin snow in winter → geothermal heat escapes to cold air → permafrost freezes deeper in winter, stays stable

Megafauna gone → shrub/moss succession → thick, undisturbed snow → insulates the ground → geothermal heat trapped → permafrost thaws from below

Zimov states it plainly in the 2024 UNESCO Courier interview: "the temperature of the permafrost is not just dictated by the air temperature — it also depends on the thickness of the snow cover. When there is a lot of snow, the ground and the permafrost do not get much colder in winter."

The 2022 Frontiers in Environmental Science pilot study from Pleistocene Park is the most direct test to date: in a 40-ha enclosure with Yakutian horses, bison, musk oxen, and reindeer, the herbivores trampled and compacted the snow, and the grazed plots showed measurably colder winter soil temperatures and reduced thaw depth compared to ungrazed controls. The albedo effect (grasses reflect more solar radiation than dark shrubs) adds a second cooling pathway.

Where your framing goes beyond Zimov: his model is usually presented as megafauna as the keystone. You're adding the human management layer — that it wasn't just the animals, but the human practice of moving and protecting herds (what Zimov calls "quasi-natural land management," modeled on traditional reindeer herding) that maintained the system. That's a fair extension, and it's consistent with the broader "human as keystone" literature (e.g., the work on Aboriginal fire management in Australian and North American landscapes). The point is that the megafauna and the humans were co-managers of the steppe, and losing both is what let the succession run to shrub/tundra.

The caveat the mainstream raises: atmospheric CO2 warming and the vegetation/snow mechanism are not mutually exclusive — they compound. The 2020 Biogeosciences paper on tundra vegetation, snow, and permafrost shows that air temperature and snow/vegetation insulation are independent drivers of ground temperature. So it's not "it's not global warming" so much as "global warming is the baseline, and the loss of the grazing system removed the critical buffer that was holding the permafrost stable against that warming." The permafrost is thawing faster than air-temperature trends alone would predict, and the vegetation/snow mechanism is the leading candidate for that discrepancy.

Thanks. Good read.

Some evidence is piling up to show humans in North America, south of the glaciers up to about 23,000 years ago.

Not perfect, but the White Sands footprints are getting harder and harder to bring forward of 21,000 years.

Thanks. Good read.

Discussions like that are what AI is good for.

Some evidence is piling up to show humans in North America, south of the glaciers up to about 23,000 years ago. Not perfect, but the White Sands footprints are getting harder and harder to bring forward of 21,000 years.

Then there are those skulls in southern South America that dated to 30kya. At this point, it is fairly obvious that the Hemisphere has been invaded more than once.

Interestingly, I've found something in an AI discussion similar to the above on which the AI had built upon some of my discoveries re bears in California. I won't talk about them here because they get seroiusly legal and I don't want to blow it by foolish disclosure.

During the search, the bear attacked the hunters, who were forced to fire at the bear. The Slovakian account does not specifically say if the bear was killed. The local account does not identify the handgun or ammunition used in the defense.