This is a press release from the USGS Alaska Science Center
Red pepper spray, commonly used by people in bear country to ward
off aggressive bear attacks, may actually attract brown bears if used
improperly, according to preliminary research by a wildlife ecologist at
the USGS Alaska Science Center in Anchorage.
In research recently submitted for publication in the Wildlife
Society Bulletin, USGS researcher Tom Smith emphasized that although the
spray is a proven deterrent in some encounters with aggressive bears, red
pepper spray is not a bear repellent when applied to objects such as tents,
food containers, clothing or other personal belongings, "nor is it claimed
to be by most manufacturers." In fact, noted Smith, no pepper spray
manufacturers normally suggest that the spray should be used preventively.
Although it is not presently known exactly what the attracting agent in the
red pepper spray is, the irritant oleoresin capsicum is the only ingredient
common to all the sprays tested.
Smith said that although research has shown that red pepper spray
is highly effective as a deterrent in aggressive grizzly and brown bear
encounters when sprayed directly in a bear's eyes or nose, his pilot study
shows that spray residues did attract brown bears when used in
nonaggressive situations. Brown bear responses to red pepper spray-treated
sites in his study ranged from mere sniffing to
whole body rolling in the
residues, an uncommon bear behavior.
The spray is often carried as a bear protection method by hikers,
campers, biologists, rangers, hunters, and other outdoor enthusiasts. The
carrying of red pepper spray has been encouraged in some national parks
where bears are common and firearms are prohibited. Some state wildlife
and game agencies have also been encouraging the carrying of the spray in
Smith's investigations have found that "instances of people
inappropriately applying red pepper spray to objects in order to repel
bears are not uncommon." His research suggests that red pepper spray used
in this manner may actually "promote" attraction to spray-treated sites or
objects by brown bears.
"If my study observations hold true elsewhere, then red pepper
spray residues on the spray canisters, field gear, or on foliage near camps
or other human high-use areas may provide sites of interest to brown bears
and consequently risk human safety," Smith warned. In back country areas
where hikers and researchers may use the same location for extended times,
continuing indiscriminate use of the spray could cumulatively create a
potentially harmful situation for the next person who uses the campsite,
Smith said. "We are concerned that if red pepper spray is used in this
inappropriate manner, it may attract bears, result in property damage, or a
The impetus for Smith's study came after he observed a
rolling vigorously in beach gravel that had been inadvertently sprayed with
red pepper spray five days previously. A surprised Smith watched
their backs, paws skyward, vigorously rubbing their heads and back in the
red pepper-sprayed gravel. Before this observation, Smith had never seen
brown bears behave in such an unusual manner.
Smith noted that red pepper spray is a stable, weather-resistant
compound that apparently does not lose its attractant, or irritant,
properties quickly. This suggests "that even a single discharge has the
potential to attract brown bears for a significant amount of time," he
Smith's preliminary study involved spraying red pepper on gravels
along the Kulik River in Katmai National Park and then observing brown bear
responses to red pepper residues from a blind. He recorded both normal and
abnormal bear behavior at or near these study sites. In his pilot study,
Smith said that brown bears approached the treated sites 40 times, with the
spray eliciting interest more than 50 percent of the time and no response
40 percent of the time. However, Smith noted that in all instances where
bears showed no response to the treated soils, strong winds were observed
that may have "whisked the scent directly away from the bears, calling into
question whether they could have scented the spray at all."
Other unusual brown bear behavior Smith recorded on the sprayed
sites included numerous instances of sniffing, pawing, licking, rubbing
their heads in the soil, and rolling on the sites in a manner similar to
cats rolling in catnip. Before this study, Smith had spent more than 750
hours observing brown bears at Kulik River. "During that time," he said,
"I had never seen bears rubbing their heads on the ground, pawing and
licking soils, or rolling on their backs."
These novel behaviors, said Smith, arise directly from exposure to
red pepper spray-treated soils, and "hence my concern about indiscriminate
or improper use of these sprays in bear country."
"In no cases," said Smith, "were bears seen to be deterred from, or
actively avoiding, red pepper spray-treated sites. These observations," he
added, "raise serious concerns regarding the appropriate use of red pepper
spray and identify a need to educate users as to potentially harmful side
effects of their indiscriminate use as a repellent agent."
Scent, of course, is what bears rely on most to locate food in
their environment, which is why campers and other backwoods users are
encouraged to carefully rid their tents and sleeping areas of articles that
might smell, including toothpaste, food and soap. Unfortunately, said
Smith, red pepper spray, besides being an effective deterrent when sprayed
in a bear's face, is also essentially "scent in a can" that bears may be
Smith urged that until further research is conducted, people who
carry red pepper spray in bear country should not test-fire newly purchased
red pepper spray near camps or other human high-use areas. As an additional
precaution, Smith advises that once fired, the canisters should not be kept
in or near the tents of sleeping persons because of the possibility that
red pepper spray residues on canister nozzles may attract bears.
Smith's work has been reviewed by other bear biologists in the U.S.
Department of the Interior and submitted for publication in the Wildlife
Society Bulletin. In addition, his observations have been anecdotally
supported by other researchers in bear habitat. Smith said USGS will
conduct more research on red pepper spray and bears this year. Smith's
future research will focus on discovering just how attractive red pepper
spray is to bears, the distance at which a bear can scent the red pepper
spray, and if a bear might be attracted to a canister that has been fired
and which has some spray residue on its exterior. Smith's preliminary work
showed that bears were picking the scent up from more than 75 meters away.
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