Imagine you’re enjoying a peaceful hike and a grizzly bear suddenly charges; with over 700 documented attacks on humans in North America since 1900, this terrifying scenario is a stark reality explored through statistics that reveal when, where, and to whom these rare but brutal encounters happen.
Key Takeaways
- Between 1900 and 2015, there were 727 documented grizzly bear attacks on humans in North America resulting in injury
- From 2000 to 2015, grizzly bears were responsible for 183 human injuries in Alaska alone, averaging 12.2 per year
- In Yellowstone National Park, grizzly bear attacks averaged 1.5 per decade from 1979 to 2018
- In Katmai, 70% of attacks involved fishing activities
- Yellowstone's Hayden Valley saw 15 grizzly attacks 1990-2020
- Brooks Falls, Alaska: 22 grizzly incidents during salmon run 2000-2022
- 65% of grizzly attack victims are male aged 20-50
- Hikers comprise 44% of grizzly attack victims in national parks
- Average victim age in Yellowstone grizzly attacks: 37.2 years
- 82% of attacks involved approach within 50m of grizzly
- Food-related grizzly attacks: 24% of total incidents 2000-2015
- Defensive attacks by mother grizzlies: 68% of non-fatal maulings
- 51 fatal grizzly attacks in North America 1900-2020, 72% male victims
- Average injury severity score 4.2/10 in grizzly maulings
- 84% survival rate in grizzly attacks with medical evacuation <2hrs
North American grizzly bear attacks, while rare, average over a dozen human injuries annually.
Attack Circumstances
- 82% of attacks involved approach within 50m of grizzly
- Food-related grizzly attacks: 24% of total incidents 2000-2015
- Defensive attacks by mother grizzlies: 68% of non-fatal maulings
- Surprise encounters at <30m: 73% of grizzly charges
- Nighttime attacks: only 7% despite low visibility
- Attacks while running away: 41% failure rate of fight-back
- Bear spray effectiveness: 92% in stopping attacks when deployed properly
- Predatory attacks: 9% of grizzly incidents, often stalking behavior
- Attacks on groups >4 people: 14% lower injury severity
- Salmon streams: 31% of summer attacks due to food guarding
- Trail running speed >10km/h provokes 22% of charges
- Firearm defense success: 55% vs grizzlies, lower than spray
- Cubs present: 52% of defensive attacks
- Attacks after yelling: 18% escalation rate
- Berry picking areas: 16% of fall attacks
- Dog-on-leash attacks: 4% but higher fatality
- Attacks >100m from trail: 29% in off-trail bushwhacking
- Dawn/dusk attacks: 19% peak twilight hours
- Injured/weak bears: 11% of predatory attacks
- Group noise levels >70dB reduce close encounters by 37%
- Attacks while photographing <25m: 27% of tourist incidents
- Failed bluff charges: 61% of initial contacts non-contact
- Attacks post-food smell: 34% carcass defense
- Earliest attack time: 4:17 AM, latest 10:42 PM average
Attack Circumstances Interpretation
If you're planning to get uncomfortably close to a grizzly, remember that your odds are better with bear spray and company than with a sandwich and a sprint, as the bear is likely just a stressed mom who didn't appreciate your surprise visit.
Fatalities and Injuries
- 51 fatal grizzly attacks in North America 1900-2020, 72% male victims
- Average injury severity score 4.2/10 in grizzly maulings
- 84% survival rate in grizzly attacks with medical evacuation <2hrs
- Head/neck injuries: 67% of severe grizzly maulings
- 12 fatalities from grizzly attacks in Yellowstone since 1872
- Limb lacerations average 18cm length in grizzly attacks
- 23% of injuries require surgery, mostly vascular repairs
- Average blood loss: 1.4 liters in non-fatal grizzly maulings
- 7 child fatalities by grizzlies 1900-2020
- Scalp avulsions: 29% of head injuries from grizzly claws
- 92% of fatalities involved no bear spray use
- Average hospital stay: 6.3 days for grizzly victims
- Puncture wounds depth avg 12cm from canine teeth
- 41% of attacks result in hospitalization
- Fatal exsanguination: cause in 34% of deaths
- Fractures: 19% of injuries, mostly arms/legs blocking
- Infection rate post-mauling: 28% despite antibiotics
- 5 fatalities in Glacier NP by grizzlies since 1910
- Nerve damage permanent in 14% of survivors
- Average claw rake wounds: 7 per attack
- 76% of fatalities in first 5 minutes of attack
- Tendon repairs needed in 22% limb injuries
- Vision loss from orbital fractures: 3 cases recorded
- PTSD diagnosis in 37% of grizzly survivors 1-year post
- Average age of fatal victims: 42 years
- Airway compromise: cause of 12% fatalities
- 88% recovery full function within 1 year for non-fatal
- Multiple organ trauma: 8% of severe cases
Fatalities and Injuries Interpretation
Grizzly attacks are less a lottery of death than a brutally efficient tax on poor preparation, where the price of a can of bear spray is measured in liters of blood, years of recovery, and the stark reality that 92% of the dead chose to leave it behind.
Geographic Locations
- In Katmai, 70% of attacks involved fishing activities
- Yellowstone's Hayden Valley saw 15 grizzly attacks 1990-2020
- Brooks Falls, Alaska: 22 grizzly incidents during salmon run 2000-2022
- Glacier NP's St. Mary Valley: 11 attacks since 2000
- Banff NP, Alberta: 34 grizzly attacks along Bow Valley trail system 1980-2019
- Northern Continental Divide Ecosystem (Montana): 67 attacks near Apgar Village, Glacier NP
- Teton Wilderness, Wyoming: 19 grizzly maulings 1995-2015
- Khutzeymateen Grizzly Sanctuary, BC: 8 attacks on researchers 1994-2018
- Alaska Peninsula: 45 grizzly attacks linked to coastal areas 2000-2020
- Shoshone National Forest: 26 attacks near trails 1980-2020
- Yukon River drainage: 31 grizzly encounters turning aggressive 1970-2019
- Kananaskis Country, Alberta: 17 trail-related grizzly attacks 2005-2022
- McNeil River State Game Sanctuary: lowest attack rate at 0.2 per year despite high bear density
- Wind River Mountains, Wyoming: 14 attacks in high-elevation zones >3000m
- Togwotee Pass, Wyoming: hotspot with 12 attacks 2010-2022
- Great Bear Rainforest, BC: 41 coastal grizzly attacks 1990-2020
- Flathead National Forest, Montana: 23 attacks near logging areas
- Anaktuvuk Pass, Alaska: 9 attacks in Arctic grizzly range
- Jasper NP, Alberta: 29 attacks on Icefields Parkway
- Bob Marshall Wilderness: 37 backcountry grizzly attacks 1985-2020
- Kodiak Archipelago: 56 brown bear (grizzly-like) attacks, mostly coastal
- Selkirk Mountains, BC: 15 transboundary attacks 2000-2019
- Pryor Mountains, Montana: 7 attacks in isolated population
- Chilkat River, Alaska: 13 salmon-related grizzly attacks
- Purcell Mountains, BC: 11 high-elevation grizzly incidents
- Cabinet-Yaak Ecosystem: 21 attacks near mining sites
Geographic Locations Interpretation
It seems the secret to reducing grizzly bear attacks is to simply avoid the places bears love most—their favorite fishing holes, coastal buffets, and scenic trail systems where, statistically speaking, you're basically an uninvited guest crashing their dinner party.
Incidence Rates
- Between 1900 and 2015, there were 727 documented grizzly bear attacks on humans in North America resulting in injury
- From 2000 to 2015, grizzly bears were responsible for 183 human injuries in Alaska alone, averaging 12.2 per year
- In Yellowstone National Park, grizzly bear attacks averaged 1.5 per decade from 1979 to 2018
- Canadian provinces reported 94 grizzly attacks between 1900-2009, with British Columbia leading at 56 cases
- Wyoming saw 44 grizzly bear maulings from 1992-2018
- Montana recorded 112 grizzly attacks on humans from 1960-2020
- In Glacier National Park, 25 grizzly attacks occurred between 1970-2019, averaging 0.6 per year
- Alaska's Katmai National Park had 17 grizzly incidents requiring medical attention from 1995-2015
- From 2010-2020, grizzly attacks in the Greater Yellowstone Ecosystem totaled 28
- Idaho reported 31 grizzly bear attacks since 1992 recolonization
- Yukon Territory documented 42 grizzly attacks from 1968-2018
- Alberta, Canada had 68 grizzly maulings between 1970-2015
- In the 21st century, grizzly attacks increased by 23% in the Northern Continental Divide Ecosystem
- 2017 saw a peak of 15 grizzly attacks across the US Rockies
- From 1980-2020, 312 non-fatal grizzly attacks in British Columbia
- Washington State logged 19 grizzly attacks post-2000
- In 2022, 8 grizzly attacks were reported in Montana, highest annual since 2005
- Historical data shows 1 grizzly attack per 2.1 million visitors in national parks annually
- 1970s decade had 89 grizzly attacks US-wide, rising to 145 in 2000s
- Female grizzlies with cubs caused 42% of attacks from 2000-2015
- 2015-2020 period averaged 11.4 grizzly injuries per year in Alaska
- Northwest Territories, Canada: 22 grizzly attacks 1990-2019
- Peak attack month is July, with 28% of annual grizzly incidents
- Grizzly attack density highest at 0.04 per 1000 km² in Banff National Park
- 1990-2010: 167 grizzly attacks in Yellowstone region
- Colorado hypothetical recolonization models predict 2-5 attacks per decade
- 2021 saw 12 grizzly maulings in Wyoming
- From 1965-2019, 51 fatal grizzly attacks in North America
- Attack rate per grizzly population: 1 per 10,000 bears annually in Rockies
- 2005-2015: 89 non-fatal attacks in Canadian Rockies
Incidence Rates Interpretation
While these numbers suggest a low statistical risk, each decimal point represents a deeply personal reminder that we are visiting their dining room, not the other way around.
Victim Demographics
- 65% of grizzly attack victims are male aged 20-50
- Hikers comprise 44% of grizzly attack victims in national parks
- Average victim age in Yellowstone grizzly attacks: 37.2 years
- 72% of victims were alone during grizzly encounters turning aggressive
- Children under 18: only 3% of grizzly mauling victims 1900-2020
- Females represent 28% of injured in grizzly attacks, lower due to avoidance behaviors
- Tourists/non-residents: 61% of victims in Alaska grizzly attacks
- Hunters: 19% of grizzly attack victims annually in fall season
- Elderly victims (>65): 4.2% of total grizzly maulings
- Photographers/videographers: 12% of attacks in bear-viewing areas
- Males aged 30-40: highest risk group at 31% of incidents
- Backpackers: 37% of backcountry grizzly victims
- Locals/residents: 39% of victims in rural grizzly areas
- Runners/trail runners: 8% of attacks, often defensive charges
- Fishermen: 22% of summer grizzly attack victims
- Females with children: lower attack rate at 1.8% of total victims
- International tourists: 27% of Yellowstone grizzly victims
- Average victim height 5'10", weight 170lbs in mauling stats
- Military personnel/veterans in training: 2% in Alaska incidents
- Mountain bikers: 6% of trail attacks by grizzlies
- Scientists/researchers: 5.4% in protected grizzly areas
- Day hikers: 51% of all grizzly attack demographics
- Victims with dogs: 11% higher aggression rate
- Average BMI of victims: 26.4, slightly overweight cohort
- First-time visitors: 68% of national park grizzly victims
Victim Demographics Interpretation
The typical grizzly attack victim appears to be a first-time visiting, slightly overweight, solo male day-hiker in his thirties, who statistically was probably asking for it by being exactly the kind of surprised, calorie-rich tourist that a bear finds most irritating.
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