More than 200 Documented Defensive Killing of Grizzly Bears in Contiguous 48, 2002-2023

Image of grizzly bear  by Troy Nemitz, used with permission. 

About five to ten times as many grizzly bears are killed in defense of self and others as have been readily known to the public.

On January 15, 2025, the Department of the Interior, Fish and Wildlife service, published a proposal to revise the listing of the grizzly bear in the contiguous 48 states. The proposal includes the most complete information on grizzly bear mortality to date.

Studies to determine how effective various tools are in defending against attacks by grizzly bears suffer from serious selection bias. If the defense is successful, and no humans are harmed, the chance of the attack being published is greatly reduced. When humans are mauled or killed by a grizzly bear, the event is newsworthy. When no human is harmed, the event is far less likely to be recorded in a way available to the researcher.

In the contiguous 48 states of the United States, the Ursus arctos horribilis (grizzly bear) population has been under intense study for several decades. The 2025 proposal by the Fish and Wildlife service includes detailed statistics about grizzly bear mortality in the contiguous 48 states. There are severe criminal penalties for not reporting the killing of grizzly bears. This is the best data set available to determine the extent of defensive incidents where humans defended themselves against grizzly bears, and the bears were killed.

The data in the table covers the period from 2002 through 2023. The data is divided between independent bears (bears which live by themselves) and dependent bears (bears which depend on the mother for survival).

During the 22 years, 1,213 deaths of independent bears were recorded. Of those, 211 were investigated and recorded as killed in defense of human life.  Only 70 of the 1,213 deaths were listed as natural mortalities.    479 independent grizzly bears  were deliberately killed by federal government officials as part of the management process, mostly dangerous bears and bears predating on livestock. Human related accidents, mostly motor vehicle and trains, accounted for the deaths of 152 independent bears. 119 independent bears were illegally killed. There were 93 mortalities  of independent bears under investigation, presumed to be illegal killing by humans. There were 59 cases of mistaken identity killing of bears.

Total mortality of dependent bears was 478. 90 dependent bears were listed as dying because of self defense incidents. Orphaned bears were included in this number. 115 dependent bears were killed in the management program. 122 dependent bears were listed as dying of natural causes.   Accidents accounted for 96 dependent bears. 27 were illegally killed. 19 mortalities of dependent bears are under investigation. There were 2 mistaken identity killing of dependent bears.

There were 24 bear mortalities where the cause was unknown.

Human caused mortality is listed as the major cause of grizzly bears deaths in the contiguous 48 states. The numbers show an average of only 77 deaths of grizzly bears per year, for a population of at least 2000. This is about 3.9% per year. Grizzly bear populations can easily increase by 7% per year.  Alaska harvests about 6% of Ursus Arctos  per year. A harvest of up to 15% may be sustainable. The theoretical limit is listed as slightly over 18%.  It is not surprising the grizzly bear population in the contiguous 48 states has been steadily increasing, in spite of human related mortality. Mortalities caused by humans defending human life are about 13 per year, or about .64% of the grizzly bear population per year.

The chart of bear population in the Greater Yellowstone Ecosystem covers less than half of the grizzly bear population in the contiguous 48 states.

Once bear populations reach higher densities, killing of cubs, mostly by adult male bears, slows the rate of population growth.

The numbers show the use of firearms is extremely effective to defend against grizzly bear attacks. Not a single person, armed with a firearm, was killed by a grizzly bear in the 211 cases where a bear was killed.

From 2002 to 2023, inclusive, the database maintained by this correspondent and colleagues only shows 36 grizzly bears killed from 2002 to 2023 in the lower 48 in defense of self and others. There were another 18 incidents where investigators did not find a dead bear.

The numbers supplied by the Fish and Wildlife service only count incidents where a dead bear was found. That happens in about 2/3 of the defensive incidents found by this correspondent and others. It is reasonable to believe the actual numbers of defensive incidents is at least 50% greater than the number of dead bears. It may be much higher, because of built in selection bias. If the bear/bears run off because of shots fired, and there is no blood or evidence of harm, the incidents are much less likely to be recorded. Warning shots appear to be effective about 72% of the time, when they are attempted. This means there could be a large number of incidents where bears were driven off without being killed or wounded, where the incentive to report the incident would be small.

Extrapolating the numbers from the defensive incidents where grizzly bears were killed indicates the total number of defensive incidents during the 22 years is over 300 in the contiguous 48 states, and may be much higher.  An average of 13 adult grizzly bears were killed in defense of self and others in the contiguous 48 states per year, or about .64% of the population.  Management killings are about twice that amount  at 1.3% (580).

12 people were killed by grizzly bears in the contiguous 48 states from 2002 to 2023. None of those people were armed with a firearm or firearms.  In three of the 12 cases, bear spray was used before the person was killed by the bear.

©2025 by Dean Weingarten: Permission to share is granted when this notice and link are included.

Gun Watch  

Source: http://gunwatch.blogspot.com/2025/08/more-than-200-documented-defensive.html