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Fatal Attacks by American Black Bear on People: 1900-2009

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At least 63 people were killed in 59 incidents by non-captive black bear (Ursus americanus) during 1900–2009. Fatal black bear attacks occurred in Canada and Alaska (n = 49) and in the lower 48 states (n = 14). There were 3.5 times as many fatal attacks in Canada and Alaska but only 1.75 times as many black bears, and much less human contact for black bears in Canada and Alaska. There was a weak positive correlation (rs = 0.56, P ≤ 0.000) between the estimated size of a bear population within a given jurisdiction and the number of fatal black bear attacks. Some jurisdictions had no fatal black bear attacks but had large estimated black bear populations. Of fatal attacks, 86% (54 of 63, 1.08/yr) occurred between 1960 and 2009. There was positive linear relationship between the number of fatal black bear attacks per decade and human population size in the United States and Canada per decade (r2 = 0.92, β = 0.000, P ≤ 0.001). Of fatal attacks, 91% (49 of 54) occurred on parties of 1 or 2 persons. In 38% (15 of 40) of incidents, peoples' food or garbage probably influenced the bear being in the attack location. We judged that the bear involved acted as a predator in 88% (49 of 56) of fatal incidents. Adult (n = 23) or subadult (n = 10) male bears were involved in 92% (33 of 36) of fatal predatory incidents, reflecting biological and behavioral differences between male and female bears. That most fatal black bear attacks were predatory and were carried out by 1 bear shows that females with young are not the most dangerous black bears. As a result of our research agencies managing black bear can more accurately understand the risk of being killed by a black bear, and can communicate this to the public. With training, people can learn to recognize the behaviors of a bear considering them as prey and can act to deter predation. © 2011 The Wildlife Society.
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Research Article
Fatal Attacks by American Black Bear on People:
1900–2009
STEPHEN HERRERO,
1
Environmental Science Program, Faculty of Environmental, Design, University of Calgary, Calgary, AB, Canada
T2N 1N4
ANDREW HIGGINS, 2336 Chicoutimi Drive, N.W., Calgary, AB, Canada T2L OW3
JAMES E. CARDOZA, Division of Fisheries and Wildlife, Field Headquarters, 1 Rabbit Hill Road, Westborough, MA 01581, USA
LAURA I. HAJDUK, Division of Fisheries and Wildlife, Field Headquarters, 1 Rabbit Hill Road, Westborough, MA 01581, USA
TOM S. SMITH, Wildlife and Wildlands Conservation Program, Faculty of Plant and Wildlife Sciences, Brigham Young University, 451 WIDB,
Provo, UT 84602, USA
ABSTRACT At least 63 people were killed in 59 incidents by non-captive black bear (Ursus americanus)
during 1900–2009. Fatal black bear attacks occurred in Canada and Alaska (n¼49) and in the lower
48 states (n¼14). There were 3.5 times as many fatal attacks in Canada and Alaska but only 1.75 times as
many black bears, and much less human contact for black bears in Canada and Alaska. There was a weak
positive correlation (r
s
¼0.56, P0.000) between the estimated size of a bear population within a given
jurisdiction and the number of fatal black bear attacks. Some jurisdictions had no fatal black bear attacks but
had large estimated black bear populations. Of fatal attacks, 86% (54 of 63, 1.08/yr) occurred between 1960
and 2009. There was positive linear relationship between the number of fatal black bear attacks per decade
and human population size in the United States and Canada per decade (r
2
¼0.92, b¼0.000, P0.001).
Of fatal attacks, 91% (49 of 54) occurred on parties of 1 or 2 persons. In 38% (15 of 40) of incidents, peoples’
food or garbage probably influenced the bear being in the attack location. We judged that the bear involved
acted as a predator in 88% (49 of 56) of fatal incidents. Adult (n¼23) or subadult (n¼10) male bears were
involved in 92% (33 of 36) of fatal predatory incidents, reflecting biological and behavioral differences
between male and female bears. That most fatal black bear attacks were predatory and were carried out by
1 bear shows that females with young are not the most dangerous black bears. As a result of our research
agencies managing black bear can more accurately understand the risk of being killed by a black bear, and can
communicate this to the public. With training, people can learn to recognize the behaviors of a bear
considering them as prey and can act to deter predation. ß2011 The Wildlife Society.
KEY WORDS American black bear, fatal bear attacks, Ursus americanus, predation on humans, human–black bear
conflict.
Although American black bear (Ursus americanus) are mem-
bers of the order Carnivora, they are largely omnivorous
(Pelton 2003). Black bear have compact and strong muscles
and can run fast for short distances. Their jaws, teeth, fore-
arms, and claws can inflict serious injury to other bears and
animals, including people. Aggression and social interaction
are components of determining dominance related to occu-
pying space, feeding, and mating. Most individual black bear
have the strength to overcome an unarmed person. However,
observations of aggressive black bear-black bear and black
bear–human interactions have shown that physical contact is
a minor component of aggressive interactions (Jordan 1976,
Eager and Pelton 1979, Herrero 1985). Black bear are
opportunistic predators but in most populations diet is prim-
arily derived from plants and insects (Pelton 2003).
Black bear are a biologically successful, widely distributed
species, found from northern Mexico to, and occasionally
beyond, the northern limit of trees in Canada and Alaska. A
population estimate for the early 2000s, based on corre-
spondence with most jurisdictions where black bear are
found, estimated 750,235–917,650 black bears in North
America (Hristienko and McDonald 2007). During the
1980s and 1990s most black bear populations grew numeri-
cally and geographically (Williamson 2002). In the United
States and Canada, 60% of states and provinces reported
increasing populations, and all other populations appeared to
be either stable or fluctuating with no clear trend (Garshelis
and Hristienko 2006). Between 1988 and 2001 black bear
numbers in Canada and the United States were estimated
to have increased between 17.6% and 19.8% (Garshelis
and Hristienko 2006). Black bear numbers and their wide
distribution lead to extensive contact with another widely
distributed, numerically successful mammal, human beings.
Black bear are often drawn into conflict situations
with humans after being attracted by peoples’ food or edible
garbage (Eager and Pelton 1979, Herrero 1985). Defensive
threat behavior is common when a person or other bear
comes within the bear’s overt reaction distance (Herrero
et al. 2005:363). When this occurs black bear behave as
Received: 1 October 2009; Accepted: 8 July 2010
1
E-mail: herrero@ucalgary.ca
The Journal of Wildlife Management 75(3):596–603; 2011; DOI: 10.1002/jwmg.72
596 The Journal of Wildlife Management 75(3)
if they were stressed. If bears do not flee they usually direct
threats at the intruder. Black bear threats may include
physical behaviors such as swatting the ground with one
or both front paws, short charges (i.e., running toward)
but stopping short of contact, slow and deliberate
approaches, and clacking of the teeth by bringing the upper
and lower jaws together (Eager and Pelton 1979, Herrero
1983). These displays may be directed at other bears or
people. Sounds emitted by a black bear are also a component
of threat behavior. These have been described as huffing,
snorting, gurgling, and loud growling (Jordan 1976, Eager
and Pelton 1979, Herrero 1983). Threat behaviors seldom
lead to physical attack by a black bear provided the bear is
given the personal space it requires to feel secure. Most fatal
attacks by black bear on people have been judged as predatory
(Whitlock 1950; Herrero 1985; Herrero 2002; Herrero
and Higgins 1995). Bears did not typically display physical
or vocal defensive threat behaviors during predatory
attacks (Herrero 1985, 2002; Herrero and Higgins 1995).
Behavioral components such as stalking (i.e., searching);
full out attack typically using paws, claws, jaws, and teeth,
consuming a person’s flesh; and dragging, guarding, and
burying a body support the classification of predation
(Herrero and Higgins 2003).
In 1948 a young girl was killed in a predatory attack by a
black bear near Sault Saint Marie, Michigan. This became
the first fatal black bear attack to be assessed in the scientific
literature (Whitlock 1950). Since then serious and fatal
black bear-inflicted injuries have been studied as part of
analyzing bear attacks in several jurisdictions (Middaugh
1987; Gunther 1994; Gniadek and Kendall 1998; Herrero
and Higgins 1998, 1999, 2003; Miller and Tutterow 1998).
Each year in North America there are human injuries
inflicted by black bear. The worst of these, fatal attacks,
can be minimized by understanding the circumstances
associated with such attacks. Without this knowledge, fear
and supposition may play an undeserved role in assessing the
danger posed by black bear. Peoples’ acceptance of some
probability of black bear-inflicted injury, even fatal injury,
is essential for bear conservation. At the same time the public
must trust that bear managers have vigorously tried to reduce
chances of serious injury through studying and understand-
ing attacks and sharing this information with the public.
Accurate data regarding risk of fatal attacks by black bear
may influence risk perceptions and generate public support
for bear management and conservation (Knuth et al. 1992,
Gore et al. 2007).
Our objectives were to: 1) locate, categorize, and analyze
accurate records of all fatal attacks by American black bear in
the United States and Canada, 1900–2009, and 2) synthesize
implications for management, including how fatal attacks
may be avoided. We focused on fatal attacks because these
are the most extreme and undesirable encounter between a
human and a black bear and also because detailed investi-
gations are usually conducted for fatalities. We considered
bear and human-related variables associated with fatal
attacks, defined and described below, and trends in fatal
attacks over time.
STUDY AREA
Our study area was the United States, and Provinces and
Territories of Canada that had black bear populations any-
time between 1900 and 2009. Although black bear are found
in northern Mexico we did not search for records of fatal
black bear attacks there because discussion with persons
knowledgeable about black bears in Mexico did not identify
any fatal attacks (D. Doan-Crider, Comfort, Texas, personal
communication). For some analyses we grouped fatal attacks
into categories of those occurring in Canada and Alaska
versus the lower 48 States because there are more black bears
and fewer people in Canada and Alaska as compared to the
lower 48 States.
METHODS
The first author began a database with details regarding
injuries inflicted by American black bear or brown (grizzly)
bear (Ursus arctos) in 1967 (Herrero 1970, 1985, 2002). This
database is now in File Maker Pro
TM
(File Maker Pro, Santa
Clara, CA), Our current analysis focuses on fatal injuries
inflicted by black bear, 1900–2009. During the 1990s we
contacted all of the States (U. S.), provinces and territories
(Canada), and national parks that had populations of black
bear anytime during the study period. We requested records
of fatal bear attacks that had occurred since 1900 and sought
missing details by correspondence or phone. We also
searched published literature, both scientific and popular,
as well as newspapers that were electronically accessible.
When possible we used records provided by park, state,
province, or territorial wildlife management agencies.
Otherwise, we used what seemed to be the most reliable
sources of information available. Since 2000 we have used
various computer search engines to find basic information
regarding fatal attacks; since 2006 we have exclusively used
Google
TM
(Google Inc., Mountain View, CA) to assist our
searching. After a search engine identified a possible fatal
attack we then contacted relevant agencies for confirmation
and details.
Some fatal attacks that occurred during the early decades of
the 20th century may not have been reported and thus may
not be included in our study; however because of the nature
of information sources we used we think few such incidents
exist. Inaccuracies or assumptions may have been reported
regarding the details of some incidents, however we designed
our data collecting methods to minimize inaccuracies. For
our database, we used and tried to corroborate multiple
sources of information about fatal attacks. When in doubt
regarding some piece of information for a specific incident
we left the data field blank. Depending upon the variable
under study and the insights we wanted to develop, we
present our results either in terms of the number of
people killed or the number of incidents in which people
were killed.
Data details for some variables associated with fatal attacks
were not available. In such situations we report the number of
fatal attacks or incidents for which we do have data. For
Herrero et al. Fatal Attacks by Black Bear 597
example, regarding the attacking black bear’s apparent
health, we had data for 34 incidents. We represent the
numbers of times an apparent health problem was identified
as 32% (11 of 34). This means we only had data for this
variable for 34 incidents, and for 11 of these the bear had a
wildlife management agency described apparent health prob-
lem, such as very low body weight, or significant injury.
We may also have underestimated the number of predatory
attacks because data required to meet our definition of pre-
dation were not always available. We only included incidents
where the black bear fatally attacked a person. We did not
include an incident where a boy died of respiratory problems
after fleeing from a black bear (Antonio Hansell, New
Hampshire, 3 August 2004) because the boy did not die
as a result of physical attack by a bear. Nor did we include 2
other fatalities where a bear was involved but did not directly
cause the person’s death (F. Beals, Maine, 1910; and M.
Wiig, British Columbia, 1966). We did include an incident
where a black bear chased a boy up a tree, injured him, and
was responsible for the boy falling and dying (M. Patterson,
Porcupine Mountains State Park, Michigan, 19 June 1978).
Here physical injury by a bear led to death. Also, we did not
include incidents where a captive black bear killed a person.
To reduce subjective interpretation of incidents, we relied
on as rigorous definitions as possible of classification terms.
Some of these terms were defined in previous publications
(Herrero and Higgins 2003). Our classification terms and
definitions follow. 1) Predation: a series of behaviors, includ-
ing searching, following or testing, attacking (capturing),
killing, sometimes dragging a person, sometimes burying
them, and often feeding upon them (to be classified as
predation in our study, killing and some related behaviors
had to be reported); vocalizing and stress behaviors by the
bear were usually absent; 2) Attempted predation: behaviors
associated with predation occurred but killing did not; 3)
Predatory attacks: incidents that involved predation or
attempted predation; 4) Front-country: locations within
2 km of traveled roads (i.e., paved roads or a high-speed
gravel roads that had regular vehicle traffic), including auto
access campgrounds, landfills, picnic areas, and rural home
sites and also including the portion of hiking trails within
2 km of traveled roads; 5) Back-country: locations >2km
from traveled roads, including trails, backcountry lodges,
backcountry cabins, and backcountry campsites; and 6)
Peoples’ food or garbage: peoples’ unsecured food or edible
garbage. We considered peoples’ food or garbage to have
influenced an attack when the food or garbage was within
100 m of the attack site and if the black bear had some
behavior directed toward exploring or consuming people’s
food or edible garbage.
We used Spearman’s rank correlation to test for a corre-
lation between black bear estimated population size in each
jurisdiction during the early 2000s and the total number of
fatal attacks per jurisdiction (Hristienko and McDonald
2007). We used linear regression to quantify the relationship
between human population size in the United States and
Canada per decade and the number of fatal black bear
attacks per decade. We determined significance at the
a¼0.05 level for all statistical tests. We conducted all
statistical tests in SAS 9.1 (SAS Institute Inc., Cary,
NC). Decade data for the United States population 1900–
1999 came from Demographia and the Public Purpose
(2010). Data for the US population through 2009 came
from Information Please (2010). All data for Canada’s popu-
lation came from Wikimedia Foundation Inc. (2010).
RESULTS
We determined 63 people were killed in 59 incidents by a
non-captive black bear during 1900–2009 (Table S1, avail-
able online at www.onlinelibrary.wiley.com). Of the fatal
attacks 49 occurred in Canada and Alaska and 14 occurred
in the lower 48 states (Fig. 1). There were 3.5 times as many
fatal attacks in Canada and Alaska, but there were only 1.75
times as many black bears and much less human contact (due
to fewer people in black bear habitat) for black bears in
Canada and Alaska. There was a weak positive correlation
(r
s
¼0.56, P0.000 between the estimated size of a bear
population within a given jurisdiction and the number of
fatal black bear attacks. Some areas had no fatal black bear
attacks but in the early 2000s had numerically large estimated
black bear populations (i.e., CA: 31,000 black bears; ID:
22,500 black bears; ME: 23,000 black bears; MT 20,000
black bears; and OR: 27,500 black bears; Hristienko and
McDonald 2006).
Along with increases in black bear and human populations,
fatal attacks per decade increased over time (Fig. 2). Of the
fatal attacks, 86% (n¼54: 1.08/yr) occurred between 1960
and 2009. There was a positive linear relationship between
the number of fatal black bear attacks per decade and human
population size in the United States and Canada per decade
(r
2
¼0.92, b¼0.000, P0.001; Fig. 3). Fatal attacks
Figure 1. Locations and numbers of American black bear-inflicted human
fatalities, Canada and United States, 1900–2009.
598 The Journal of Wildlife Management 75(3)
occurred between April and November, with 85% (52 of 61)
occurring between May and September (Fig. 4). Most
fatal attacks (70%, 30 of 43) took place during daytime
(0600 hours through 1759 hours), whereas 19% (8 of 43)
occurred during evening (1800 hours through 2359 hours)
and 12% (5 of 43) occurred at night (2400 hours through
0559 hours). Fatal attacks occurred in both back-country
(61%, 30 of 49) and front-country locations (39%, 19 of
49). In 87% of incidents (7 of 8) the attack persisted for
between 10 min and several hours. There was only 1 incident
<2 min.
Of fatal attacks, 91% (49 of 54) were on parties of 1 or
2 persons (Fig. 5) and 69% (37 of 54) were on parties of
1 person. In most cases, only 1 person was killed during a
fatal attack, however, in 3 incidents 2 or 3 people were killed
by the same bear within several hours. In 1 incident a black
bear killed a person one day and then a few days later
attempted to kill another person. In 95% (19 of 20) of
incidents, surviving people in the party reported not sensing
the bear until it was <50 m distant. Humans of various ages
and sexes were killed (Fig. 6). People killed were participat-
ing in a variety of activities prior to being attacked (Table 1).
Our impression is that any activity that brings people and
black bear into possible close proximity may very rarely be
associated with fatal attack. Bear cayenne pepper spray was
not used for defence during any of the fatal attacks.
There were no incidents in which there was clear evidence
that >1 bear was known to have been involved in the fatal
attack. Based on strict criteria as described in our methods,
we judged that the bear involved acted as a predator in 88%
(49 of 56) of incidents. Adult (n¼23) or subadult (i.e.,
weaned from mother but not yet breeding; n¼10) male
bears were involved in 92% (33 of 36) of predatory fatal
incidents. In 8% (3 of 36) of fatal incidents an adult female
bear with young inflicted the fatality. No incidents were
attributed to a single adult female or subadult female bear.
In 68% (23 of 34) of incidents the bear was reported to have
been healthy. In 32% (11 of 34) an apparent health problem
(e.g., underweight, injured, poor condition) was identified
by agency personnel. Rabies was never identified in a bear
causing fatal injury.
In 38% (15 of 40) of incidents peoples’ food or edible
garbage probably influenced the bear being in the attack
location, as in these incidents the bear was known to have
either fed on food or garbage or showed exploratory behavior
directed toward food or garbage that was within 100 m of the
attack site. There were no incidents in which a black bear
attacked a person in apparent defence of an ungulate or other
carcass, nor were there any incidents in which a black bear
attacked and killed a person while trying to claim an ungulate
carcass. There was 1 fatality where a hunter wounded a bear,
which then attacked and killed the hunter. There were 2
separate incidents where a black bear was breaking into a
cabin and was shot and wounded by a person in the cabin. In
each case the bear attacked and killed the person.
DISCUSSION
Assessed Risk of Fatal Black Bear Attacks
Our research offers important and unique longitudinal
insight into fatal black bear attacks on people in Canada
and the United States. The risk of fatal black bear attacks
on people in our study area was extremely low. Each year,
millions of interactions between people and black bears occur
without any injury to a person, although by 2 years of age
most black bears have the physical capacity to kill a person
(Herrero 1985, 2002).
Although the risk of a black bear fatally attacking a person
is low, it does exist. The moderately positive correlation
between the estimated number of bears in a given jurisdiction
and the number of fatal attacks suggests that the number of
black bears in an area may be one factor contributing to
chances of fatal attack. However, 5 states had black bear
population estimates of 20,000, yet no fatal attacks. The
widespread geographic distribution of fatal attacks suggests
that they may occur in a variety of bear habitats and bear
population conditions. Fatal attacks do not appear to be
associated only with a specific black bear population, geo-
graphic area, or habitat. Fatal attacks were most numerous
during the month of August, when most black bears are
ingesting high-energy foods in preparation for denning.
Rarely, a person may be perceived as potential high-energy
prey. During August there are also many people pursuing
outdoor activities, thus increasing the chances of contact
with black bear.
0
2
4
6
8
10
12
14
16
18
No. of fatalities
Fatalities
Decade of fatality
Figure 2. Fatal American black bear attacks by decade, Canada and United
States, 1900–2009.
y = 6E-05x - 6.8306
R
2
= 0.9211, P≤
0.001
0
2
4
6
8
10
12
14
16
18
0
50,000
100,000
150,000
200,000
250,000
300,000
350,000
400,000
No. of fatal bear attacks by
decade
U.S. and Canada human
p
o
p
ulation
(
in thousands
)
Figure 3. Simple linear regression of the number of fatal black bear attacks
in the United States and Canada in each decade, 1900–2009, and the com-
bined United States and Canada human population in each decade. Each
data point represents a decade and human population increased with
each decade.
Herrero et al. Fatal Attacks by Black Bear 599
Understanding and Avoiding Fatal Black Bear Attacks
Our data suggest reasons but do not explain why a greater
proportion of fatal black bear attacks occurred in Canada and
Alaska versus in the lower 48 states; more empirical research
would benefit management. We speculate that many
black bears in Canada and Alaska had less contact with
people because the human population is about 10% of
the population in the lower 48 states. Most black bear
populations in Canada had far less hunting pressure
(Hristienko and McDonald 2007). Also many black bears
in Canada or Alaska existed in less productive and less diverse
habitat with periodic food stress, perhaps predisposing
some bears to consider people as prey. All, some, or none
of the foregoing factors may have contributed to the greater
proportion of fatal attacks in Canada and Alaska versus the
lower 48 States.
Why have the number of fatal attacks increased over time
and in most decades, and why have 86% of all known fatal
attacks occurred since 1960? Again, the data do not provide
an answer. We speculate that one contributing factor is
human population growth and increased recreational and
commercial activities of people in black bear habitat since
1960. The human population in Canada and the United
States increased by 10.6% from 1989 to 1999 (Demographia
and the Public Purpose 2010), whereas the black bear popu-
lation increased by an estimated 17.6–19.8% from 1988 to
2001 (Garshelis and Hristienko 2006). More people are
having more opportunities to interact with black bears,
which in itself increases the chances of human–black bear
interactions and thus the occasional fatal attack. The positive
linear relationship between the number of fatal black bear
attacks per decade and human population size per decade
also supports the supposition that fatal bear attacks over time
are related to the number of people potentially in bear
habitat.
Considering additional dimensions of fatal black bear
attacks on people over the past 110 years offers understand-
ing and insight for multiple avoidance strategies. First,
the number of people in parties where a person was fatally
attacked suggests that parties of 1 or 2 people are more likely
to be fatally attacked than are larger parties. Also contribu-
ting to the high representation of groups of 1 or 2 people
might be that larger groups are less frequent. We have no
data regarding the frequency of groups of different sizes in
different areas. Also numerically larger parties are probably
louder and more intimidating and better able to fight off a
black bear attack. Second, people of all ages and sexes were
victims of fatal attacks showing that fatal attacks do not favor
young, small, or older people. Because we do not know the
exposure rate to bears for different age cohorts of people we
cannot tell if bears are more likely to fatally attack a specific
age group. Our impression from our data is that young and
older people may be more vulnerable to fatal attack because
they may be perceived as less threatening and may be less able
to resist serious attack.
Third, no specific activity by a person, beyond being in bear
habitat and near the attacking bear, was associated with fatal
injuries. Most bears involved in fatal attacks were not known
to have had a history of association with people. Because fatal
attacks took place in both front- and back-country locations
2
4
6
8
10
12
14
16
18
o. of fatalities
Fatalities
0
No
Month of fatal attack
Figure 4. Month of occurrence of fatal American black bear attacks, Canada and United States, 1900–2009.
15
20
25
30
35
40
atal attacks
Incidents
0
5
10
15
1234Unknown
No. of fa
Party size attacked fatally
Figure 5. Party size and number of fatal American black bear attacks, Canada and United States, 1900–2009.
600 The Journal of Wildlife Management 75(3)
we believe that some attacking bears had prior experience
with humans and others did not.
Fourth, no one who was killed by a black bear had bear
spray. Nor was bear spray available for other party
members to deter the attacking bear. Two studies of the
effectiveness of bear spray that had capsaicin as its active
ingredient demonstrated its effectiveness but noted possible
interference with wind (Herrero and Higgins 1998, Smith
et al. 2008).
Fifth, in 38% of fatal black bear attacks, people’s food or
garbage was present and the bear either fed on it or oriented
toward it, suggesting that it may have attracted the bear and
contributed to the attack. Our experience with bear behavior
and attacks leads us to speculate that black bears that become
increasingly aggressive in going after peoples’ food or garbage
have an increased chance of initiating a serious or fatal attack.
People’s unsecured food or garbage is recognized as being
a root cause of human–bear conflict (Herrero 1985, 2002;
Beckmann et al. 2004). We are not suggesting that
poorly secured food or garbage usually contributes to fatal
attacks, however, on some occasions it has, which is another
reason for highly bear-resistant management of people’s
food and garbage. Fatal and other serious black bear
attacks that might have been predicted and avoided by
management actions have resulted in lawsuits that awarded
large settlements in compensation to the injured person It is
therefore important to recognize circumstances and black
bear behavior that might increase chances of serious or fatal
attack.
Sixth, most fatal black bear attacks were predatory and all
fatal attacks were carried out by 1 bear. With training, people
can learn to recognize the behavior of a bear that is consid-
ering them as prey. Potentially predatory approaches are
typically silent, and may include stalking or other following,
followed by a fast rush leading to contact. We know of
incidents where a black bear behaved as if it were considering
or carrying out a predatory attack and was deterred by
people’s aggressive actions such as shouting, or hitting with
rocks, fists, or sticks. Once predatory behavior is initiated it
may persist for hours unless it is deterred. After 1 person has
been killed by a black bear, the bear may attempt or succeed
in killing other nearby people, as demonstrated by the 3
incidents in which 2 or 3 people were killed. Such bears
appear to be strongly motivated, as if a switch had been
thrown. Once a black bear has killed a person there is an
increased chance that it will try to kill other people. Such
bears should be removed from the wild. Some of the attacks
that we did not classify as predatory may have in fact been
predatory, as our criteria for classifying incidents as predatory
were strict.
Seventh, male bear were responsible for most predatory
attacks, likely reflecting biological and behavioral differences
between male and female bears. Females select habitat
and behave to support security (Garneau et al. 2008). On
the other hand, male black bears typically have larger home
ranges, exposing these bears to more risks because of more
potential interactions with people, especially if the bear
population is hunted (Pelton 2003). Males represented
60% of the hunting harvest in the United States and 74%
in Canada from 1999 to 2001 (Hristienko and McDonald
2007). In Canada there was a similar total black bear harvest
(20,184 bears) as in the lower 48 states (21,080 bears), but
there was substantially less hunting pressure in Canada than
in the United States (i.e., 59,387 hunters vs. 313,727 hunters,
respectively) on a larger black bear population during 1999–
2001. With far less hunting pressure more bold males sur-
vive. Males take more risks to feed and fatten to be able to
compete with other males to breed (Noyce et al. 2001,
Garneau et al. 2008). We see predation on a person as being
a rare, high risk activity with a potentially high food reward,
in which a bear might ingest much quality food by feeding on
a person, but also will probably be killed by other humans.
Eighth, given the strength and opportunistic predation by
black bears one can ask why bears do not prey on people
more often. Part of the answer may be that bears that try to or
do prey on people are usually killed and removed from a
population’s gene pool, decreasing the frequency of any genes
the individual might have had that could contribute to
predatory attacks on people. It is well known among dog
breeders that it is possible to selectively breed for or against
aggression. It is highly likely that this selection would also be
possible for bears. It may also be true that individual bears
Table 1. Activity of victim prior to American black bear fatal attack, Canada and United States, 1900–2009.
Occupational Camping Homesite Hiking Other Unknown Total
8
a
10
b
8
c
8
d
20
e
963
a
Geological exploration ¼3; Forestry ¼2; Working on a drill rig ¼2; Trapping ¼1.
b
Back-country camping ¼6; Front-country camping ¼4.
c
Back-country homesites ¼5; Front-country homesites ¼3.
d
Hike quietly ¼3; Hike, unknown noise level ¼2; Walk ¼3.
e
Playing ¼4; Fishing ¼5; Sitting ¼3; Hunting ¼1; Filming ¼1; Jogging ¼1; Horse riding ¼1; Berry picking ¼1; Biking ¼1; Picking wild
plums ¼1; Feeding bear ¼1.
Figure 6. Age and sex of people killed by American black bear, Canada and
United States, 1900–2009.
Herrero et al. Fatal Attacks by Black Bear 601
that try to prey on people are normal bears responding to
opportunity or circumstance and that their genetic makeup is
typical of the population they are part of.
Ninth, in about 30% of fatal attacks bear health problems
were identified that may have contributed to predatory
behavior. A food-stressed bear may be more willing to take
risks such as those that occur during attempted predation.
Most bears involved in fatal attacks were thought to be
healthy.
Finally, we found no instances of a black bear attacking and
killing a person near an animal carcass. In this regard, black
bear behavior around ungulate carcasses was different than
that of brown bear (U. arctos). Brown bears occasionally
attack or even kill people in defence of an ungulate carcass
or to claim a carcass (Herrero and Higgins 1999, 2003),
thus supporting the view that black bears are generally less
aggressive than brown bears (Herrero 1985).
Reducing Risks From Black Bears
Coupled with human dimensions insight about perceptions
of risk associated with human–black bear interactions,
our results can contribute to reducing risks from black bear,
including fatal black bear attacks and circumstances associ-
ated with fatal and potentially fatal attacks. Knowledge of
fatal attacks may be used to manage assessed and perceived
risk (Knuth et al. 1992; Gore et al. 2005, 2007). Both
assessed and perceived risks from black bear are important
given the large black bear populations in Canada and the
United States. As conflicts between humans and black bear
continue to increase (Beckmann et al. 2004, Gore 2004,
Beckmann 2009) accurate information becomes funda-
mental to informed human–bear conflict management.
Communicating about black bear-inflicted human fatalities
in a statistical manner can contribute to better understanding
about black bear attacks, further reduce chances of serious
injury or death, and promote public appreciation about black
bear. However, we note that an analysis of fatal attacks that
occurred over a long time period (110 years) may make black
bear seem more dangerous than they are, because some
people may focus on the total number and ignore the long
time period during which the fatal attacks occurred.
Approaches such as intensive hunting (McDonald 2003,
Ternent 2008) or supplemental feeding (Ziegeltrum 2004)
have been suggested to reduce depredations and serious black
bear attacks. Although these approaches may be effective this
has not been scientifically demonstrated and they are con-
troversial (The Wildlife Society 2007).
MANAGEMENT IMPLICATIONS
An important management strategy to reduce potentially
fatal and other black bear attacks is to inform people how
to avoid and manage aggressive encounters with black and
other bear species. Strategies such as carrying deterrents like
bear spray, traveling in groups >2 people and being alert
for bears and bear sign are well known and are supported
by our results. It is also important to be able to recognize
bear behaviors preceding serious attacks, as we described,
and to know how to deter aggressive bears (Herrero, 1985,
Herrero, 2002, Safety in Bear Country Society 2009).
A person should try to aggressively deter or fight off a
potentially predatory bear using all possible deterrents such
as bear spray, loud noises, fists, firearms, rocks, knives, or
clubs. If a bear acts stressed and is showing defensive threat
behaviors, then a predatory attack is unlikely, which is
counterintuitive to many people because the bear is acting
aggressively. However, this aggression is defensive, and if
the bear is given space it will likely leave. Also, if an aggres-
sive female with young is encountered, a predatory attack is
extremely unlikely since most predatory attacks by black
bear were by single male bear. While female black bear, even
with cubs, seldom attack people they can be provoked into
attacking if harassed by people or dogs (Herrero 1985,
Herrero 2002; Herrero and Higgins 1999, 2003). The nature
of fatal attacks by black bear is somewhat different than
fatal attacks by brown bear. For brown bear a substantial
proportion of serious and fatal attacks are defensive and are
carried out by a female with young (Herrero 1970; Herrero
and Higgins 1999, 2003).
ACKNOWLEDGMENTS
We thank the many agencies and individuals who contrib-
uted data and insights. Our reviewers’ comments signifi-
cantly improved our paper. Particular thanks, for many
thoughtful suggestions, go to H. Hristienko, Wildlife and
Ecosystems Protection Branch of Manitoba Conservation,
Canada, and to M. Gore, Department of Fisheries and
Wildlife, Michigan State University, USA.
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Herrero et al. Fatal Attacks by Black Bear 603
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