Thursday, October 02, 2014

WY:Bear Spray v. Bullets: Flaws in the Studies

Three recent cases of bear attack in Wyoming illustrate the flaws in studies purporting to show that bear spray is superior to firearms as a defense against bears.    On September 20th, 2014 the following incident occurred.  From

(Dubois, Wyo.) – The Wyoming Game and Fish Department and the U. S. Fish and Wildlife Service both confirmed today that a third bear incident occurred this past weekend, on Saturday in northwestern Fremont County. In this incident, Lander Large Carnivore Specialist Brian DeBolt said a Grizzly bear was shot and killed “in an act of self defense” in the East Fork drainage east of Dubois. He said the bear was an adult male. He said there were no reported injuries in the incident.
It appears that in the above incident, a defense with a gun worked without any injuries to the defending humans.

There was another attack a day later, this time from a sow with cubs.  It occurred on September 21, 2014.   From
DeBolt said the man suffered only minor injuries from a bite to his side. The man's partner sprayed the bear with bear spray, causing it to stop its attack and retreat. The pair was then able to pack out and get to help.
This one is a lot harder to classify.  Do you say that the pepper spray failed, as the man was injured, or that it worked, because the bear left the scene?   Do you count it as a failure of gun defense, because, as a hunter, he probably had a gun?  Could it be a failure of a hunter to use a gun, because "bear spray studies" had convinced him to use bear spray instead?

The third attack was fatal, and occurred sometime before September 12th, probably at least five days earlier.  From
Searchers found Stewart’s body Sept. 12, on the fifth day of searching in Cub Creek, just north of Togwotee Pass in the Bridger-Teton National Forest. Preliminary investigations reveal he died of blunt force trauma, likely a bear bite.
None of the responders has reported that either pepper spray or a firearm were found at the scene.  It is not certain what species of bear killed Stewart.
Investigators found both black and grizzly hairs on Stewart’s remains. They haven’t said what species killed the researcher, but McAuslan told the Associated Press he suspects a grizzly bear.
If you are in bear country, having either a gun or pepper spray, or both, could be a good idea. In an excellent article by the Bear Attack Examiner, Dave Smith, he tears apart the idea that studies have shown bear spray to be more effective than firearms.   
 A thorough review the research on firearms and bear spray reveals that it's not possible to make a legitimate comparison of bear spray to firearms, and that Smith's research on bear spray and firearms is flawed and biased.

The Bear Attack Examiner goes on to show selection bias in the study by Tom Smith.     All 269 incidents used to classify gun defenses were incidents involving aggressive bears, while less than a third of the bear spray incidents involve aggressive bears.   Dave Smith goes on to write:

A far more significant problem is that the results of Tom Smith's study on firearms are inconsistent with the results of a 1999 study by Miller and Tutterrow on Characteristics of Nonsport Mortalities to Brown and Black Bears and Human Injuries from Bears in Alaska. Miller & Tutterrow examined more than 2,000 incidents from 1970 to 1996 when people killed bears in defense of life of property, and less than 2% of the people involved reported injuries. Instead of offering a meaningful explanation for major differences between the two studies on firearms vs bears, Smith and Herrero claimed there were no previous studies on firearms vs. bears.
I found an interesting quote from one of the authors of the bear spray studies.  From

In the Sept/Oct 2012 issue of Sports Afield, BYU professor Tom Smith, the author of Efficacy of Bear Deterrent Spray in Alaska and Efficacy of Firearms for Bear Deterrence in Alaska--says, "If I'm actually out hunting and I have a gun in my hands a suddenly a bear comes at me--do you think I'm going to lay the gun down and pick up bear spray? Are you out of your mind?" Smith also asks, "Does it really have to be a spray versus gun argument? That's ridiculous." Smith says "both guns and spray have their place... because there are times when one is the better, or the only option."
Another indicator of selection bias in the two bear spray vs. gun studies is that numerous incidents were included where people did not have time to use their gun, but no incidents were included where people did not have time to use bear spray.

I highly recommend the Bear Attack Examiner series of articles on this issue.   Dave Smith's attention to detail, citations, and reporting make it easy to know the players involved, who did the actual research, and who hyped the research to reach conclusions that simply are not supported.

©2014 by Dean Weingarten: Permission to share is granted when this notice is included.
Link to Gun Watch

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