UNITED STATES AND CANADA
Copied with the permission of Wildlife Ecology Professor, Paul Beier
from it's Northern Arizona University Site (in pdf format)
|Wildlife Society Bulletin 19:403-412. 1991||Find Table 1. by clicking HERE (updated through 1990)|
PAUL BEIER, Department of Forestry and Resource Management, University of California, Berkeley, C4 94720
Recent incidents involving cougars (Felis
and humans in southern California,
western Texas, and eastern Colorado have
prompted authorities in these states to warn
the public about the dangers of attacks and to
offer advice that might reduce such dangers.
However, only incomplete historical records
of cougar attacks are presently available to
help guide these efforts. I list all such attacks
in the United States and Canada during the
last 100 years for which I could find reports.
I examined these reports for trends in the history
and circumstances of cougar attacks, and
for traits that typify the human victims and
I attempted to document all attacks from 1 January 1890 through 31 December 1990. I searched in both scientific and popular literature, including hunter's magazines and newspapers, for reports of unprovoked attacks by wild cougars on humans. During 1897-1925, the magazine Outdoor Life encouraged letters on this topic from readers and followed most such letters with the results of the editor's inquiries to local authorities. C. Hart Merriam of the U.S. Biological Survey prepared a file (now in Dep. For. Resour. Manage., Univ. Calif., Berkeley) of newspaper and magazine clippings on attacks during 1909-1932. I found additional leads in monographs written by Young (1946), Barnes (1960), and Anderson (1983). I also obtained information from wildlife agencies in each of 12 western states (those at least partly west of 105° west longitude) and 2 provinces (British Columbia and Alberta). In each of these states and provinces, I also contacted 1 or more biologists studying cougars.
I define an attack as an incident in which the cougar bit, clawed, or knocked down a human; only attacks were tabulated. I excluded maulings by captive cougars and cases in which a person (e.g., a cougar hunter) deliberately approached or harassed a wild cougar. I define a near-attack as a cougar advancing toward a person at close range without making contact, or crouching beside a trail as if to pounce. Reports of near-attacks were relatively common, but usually impossible to verify. It was also difficult to determine if the cougar would have attacked if the person had not taken action. Therefore they were not tabulated. However, I qualitatively evaluated credible near-attacks for human behaviors that prevented physical contact.
I include a report only if it was verified by a newspaper or other published account that included statements from medical personnel or law enforcement officers, or if it was a report of the state or provincial wildlife management agency or the National Park in which the incident occurred.
Adult cougars ( 2.0 years old) were classified as underweight if they were more than 2 standard deviations below the mean body mass for their sex and subspecies (or the nearest subspecies with data) using body masses summarized by Anderson (1983:21). In general, adults were judged underweight if males and females weighed <45 and <30 kg, respectively. Males and females recorded as 12-17 months old or simply as "yearlings" were judged underweight if they weighed <30 and <20 kg, respectively (Robinette et al. 1961). When age was estimated to be 18-23 months, cutoffs of 37 and 25 kg were used. Thus only markedly underweight animals were so classified. Percentages (e.g., the proportion of victims that were children) were computed as the proportion of individuals for which the appropriate attribute (e.g., age) was recorded.
Temporal and Geographic Trends
I believe that I discovered all fatal attacks reported since 1890 and all nonfatal attacks since 1970. During 1970-1990, there were 31 nonfatal and 5 fatal attacks (6.2:l). A lower ratio of nonfatal to fatal attacks in the period from 1890 through 1969 (3.25:l) suggests that some nonfatal attacks before 1970 escaped my attention. If the ratio of nonfatal : fatal attacks during 1890-1969 was comparable to that for 1970-1990, then I did not document about 12 nonfatal attacks during the earlier period.
Cougar attacks have clearly increased during the last 2 decades, despite some possibly undocumented nonfatal attacks during the early years. There were more fatal attacks during the last 20 years (5) than during the previous 80 years (4). Also, C. Hart Merriam documented only 3 attacks (1 nonfatal, 2 fatal) in the 23 years from 1909 to 1932 versus 36 attacks (31 nonfatal, 5 fatal) reported during the last 21 years.
There were 8 attacks during December-February, 15 attacks during March-May, 21 attacks during June-August, 6 attacks during September-November, and 3 with no month recorded. This seasonal pattern of attacks may reflect increased human activity in wildlands in warmer months. The diel pattern of attacks also resembles the diurnal activity pattern of humans rather than the nocturnal activity pattern of cougars (Beier, unpubl. data). For the 32 cases in which hour of day could be determined, there were 6 attacks during 0630-1130, 15 attacks during 1130-1630, 11 attacks during 1630-2130, and no attacks during the remaining 9 hours. Of the other 21 attacks, 2 occurred at night, 6 occurred during daylight, and in 13 cases the records do not indicate time.
Twenty of the 53 attacks (38%) occurred on Vancouver Island (British Columbia), a 30,000-km2 island with 300,000 human residents. There were 10 attacks in mainland British Columbia, 5 in Texas, 4 in California, 3 each in Alberta and Colorado, 2 each in Arizona, Montana, and Washington, and 1 each in New Mexico and Nevada.
Fifteen of 54 victims (28%) were attacked close to a house or cabin, or just outside a motor home within a developed recreational area. These attacks would have been visible if someone had been watching from the home or vehicle. In several cases the house was occupied but the occupants were unaware of the attack occurring outside. The 3 most intrusive cases involved a cougar crashing through the window of an isolated cabin to attack a telephone lineman (Table 1: Kelsey Bay, B.C., 1951), a cougar who attacked a 2-year-old boy in the garage of his home in a village of 250 persons (Table 1: Lewis, Colo., 1970), and a cougar attack on a 6-year-old boy in a residential area (Table 1: , Alta., 1962). Not included in these 15 cases were 2 attacks on persons in tents or sleeping bags (Table 1: Big Bend, Tex., 1978; Strathcona Park, B.C., 1972: Hurford case); the records do not indicate whether the campsites were within developed campgrounds. In yet another case a boy was attacked while riding a bicycle (Table 1: Holberg, B.C., 1983).
Behaviors That Might Prevent an Imminent Attack
Behaviors That Did Not Avert Attacks
Human Behavior After Attacks Began
I documented only 3 cases in which alternate responses were tried. Two cases involved "playing dead." A 9-year-old boy said that he had been advised to play dead if he ever encountered a wild animal. When a cougar pounced on him as he was walking out of a lake, he followed this advice. However, the cougar continued to bite him and drag him away until his father kicked gravel at the cougar. The cougar then rushed at his 7-year-old sister; she did not play dead but screamed, causing the cougar to turn and run (Table 1: Glacier Park, Mont., 1990). In the second case (Table 1: Campbell Lake, B.C., 1972), the older brother of the 8-year-old being attacked by a cougar "shouted for him to be quiet--to play 7 dead--but the cougar started carrying him off into the bush. Then the mother came up screaming at the cougar. It dropped the boy and made off" (Vancouver Sun: 27 Jul l972).
In the third case (Table 1: Kootenay Park, B.C., 1970) a cougar attacked a 50-year-old solo hiker, clawing her arm and knocking her down. As she fell she set up her backpack as a shield, faced the cougar and (in her words) "began talking to her the way you would if you were trying to soothe a dog or cat." She continued soothing talk for 30 minutes until she heard other hikers nearby. Then she yelled for help, an approaching hiker blew a whistle, and the cougar retreated. This strategy apparently did prevent the cougar from continuing its attack. However, it was a loud shout and a loud whistle that eventually caused the cougar to retreat.
Many age estimates were made prior to the
first published criteria for age estimation
(Ashman et al. 1983) and may be imprecise. Two
offending cougars of normal body mass (when
weighed on a scale) were initially reported as
"starved" or "emaciated" by newspapers quoting
conservation officers. If the initial estimates
were wrong due to bias rather than to imprecision,
the 8 animals reported as underweight
but never weighed may have been misclassified.
If all estimated body masses are excluded,
6 of 8 attacking yearlings and 3 of 10 attacking
adults were underweight.
Only 2 offending cougars were documented to have had a disease or physical disability. One was probably rabid and caused the single double fatality (Table 1: Morgan Hill, Calif., 1909). This is the only documentation of apparent transmission of rabies from a cougar to humans; both victims died of the disease, not from the physical injuries (Storer 1923). The other diseased cougar (Table 1: Cowichan Lake, B.C., 1916) had cataracts.
One yearling cougar attacked and bit a person in Big Bend National Park 4 months after being chased, treed, drugged, and radio-collared (Table 1: Big Bend, 1987). Aversive conditioning was tried deliberately on another cougar; that animal, shot with rock salt at close range after a near-attack, returned to aggressive behavior (without physical attack) only 2 weeks later and had to be removed (C. M. Fleming and R. Skiles, Big Bend National Park, unpubl. data).
Temporal and Geographic Trends
Each year in the U.S. there are about 12 human deaths resulting from over 5,000 bites by rattlesnakes (Crotalus spp.), 40 deaths due to bee (Hymenoptera) stings, and 3 deaths due to bites of black widow spiders (Latrodectus spp.) (Weiss 1990). Dogs annually kill 18-20 people and inflict suture-requiring injuries on 200,000 US. residents (Sacks et al. 1989). In a single recent year (1979) there were 86 U.S. deaths due to lightning strikes (Natl. Center Health Stat. 1984:33-35). Thus cougar attacks are much rarer than other hazards from animals or nature. Nonetheless, these attacks have increased in the last 2 decades, probably because of increased numbers of cougars and humans during that time. Cougar populations have increased markedly in recent years in British Columbia (Hebert 1989), California (Mansfield 1986), Colorado (Anderson and Tully 1989), Nevada (Stiver 1989), Texas (Russ 1989), and Wyoming (Shorma 1989). Although other states have not estimated population trend (Smith 1989), cougar populations throughout the West probably increased during 1965-1980 as each state and province changed the legal status of the cougar from bountied predator to game species subject to controlled hunting or (in California) full protection. Simultaneously, human use of wildlands has grown, increasing the potential for encounters.
It is also possible that the decreased persecution of cougars, along with the establishment of large wilderness areas free of hunting, may allow cougars to habituate to humans as a non-threatening part of their environment. However, there is no evidence that cougars are more likely to attack humans in unhunted areas. Indeed, 57% of the attacks occurred in British Columbia, where about 200 cougars are killed annually by hunters and predator control agents (Hebert 1989).
There is no compelling explanation for the striking concentration of attacks on Vancouver Island. One speculative line of reasoning (which I raise but do not advocate) stems from the observation that several prey species taken by cougars in other parts of North America are absent from Vancouver Island. The absent species include porcupine (Erethizon dorsatum), Virginia opossum (Didelphis virginiana), cottontail rabbits (Sylvilagus spp.), coyote (Canis latrans), bobcat (Lynx rufus), badger (Taxidea taxus), and spotted and striped skunks (Spilogale putorius, Mephitis mephitis) (Burt and Grossenheider 1976). Although large ungulates are the cougar's main prey throughout its range, porcupine are important in many areas (Russell 1978). In the Santa Ana Mountains of California, porcupine are absent but opossum, cottontail, and coyotes make up over 30% of prey items and about 8% of prey biomass (Beier, unpubl. data). Because a cougar typically hunts for several days after consuming 1 deer until killing the next deer (Beier, unpubl. data), small prey may be important in sustaining a cougar between deer kills. A lack of small prey may be especially critical for a yearling animal less proficient at taking deer, and may contribute to the increased attacks on humans on Vancouver Island.
Appropriate Human Behaviors
An aggressive response may also be effective in causing a cougar to retreat after it initiates physical contact. There is no empirical support for the efficacy of "playing dead" or curling up in a fetal position once a cougar attack has begun.
In 6 of the cases tabulated here, the offending cougars were promptly killed by wildlife conservation officers but no data were recorded; in other cases data were estimated instead of measured, or necropsy records could not be located. In the future, all cougars shot after attacking humans should receive a careful postmortem examination, and the results should be filed so as to make them accessible.
I examined historical records of unprovoked attacks by cougars on humans in the U.S. and Canada during the last century (1890-1990) to determine historical trends and characteristics of victims and offending cougars. There were 9 attacks resulting in 10 human deaths and at least 44 nonfatal attacks. Attacks on humans increased markedly during the last 2 decades, during which cougar numbers and human use of cougar habitats also increased. Most victims (64%) were children; the modal age class was 5-9 years. Of 37 child victims, 35% were alone, 43% in groups of children, and 22% were accompanied by adults; 11 of 17 adult victims were alone at the time of attack. The data suggest that yearlings and under-weight cougars were most likely to attack humans. Aggressive responses on the part of intended victims may avert an impending attack and repel an attack in progress.
Acknowledgments.--I am most indebted to J. Bone, who provided leads to most of the Vancouver Island cases. The Orange County Chapter of Safari Club International generously defrayed the publication costs. This research was funded by the County of Orange, California, the California Department of Fish and Game, and California Agricultural Experiment Station Project 4326-MS. I thank all those persons who provided me with information I may not otherwise have gained; these include L. Fitzhugh, C. Fleming, J. Gonzales, H. Hash, D. Janz, M. Jalkotzy, P. Koepp, T. Malmsbury, D. R. McCullough, D. Pemble, J. Rieck, D. J. Spalding, M. Sanders, R. Skiles, S. J. Stiver, and D. Turner. F. Lindzey, R. C. Belden, N. Holler, and an anonymous reviewer made constructive comments on the manuscript.