Sunday, November 14, 2010

Bears and minivans: a love story

Bears love minivans. I stumbled across a recent (2009) paper in the Journal of Mammalogy which demonstrates this scientific fact:
ABSTRACT: Black bears (Ursus americanus) forage selectively in natural environments. To determine if bears also forage selectively for anthropogenic resources we analyzed data on vehicles broken into by bears from Yosemite National Park, California. We classified vehicles into 9 categories based on their make and model and collected data on use (2001–2007) and availability (2004–2005). From 2001 to 2007 bears broke into 908 vehicles at the following rates: minivan (26.0%), sport–utility vehicle (22.5%), small car (17.1%), sedan (13.7%), truck (11.9%), van (4.2%), sports car (1.7%), coupe (1.7%), and station wagon (1.4%). Only use of minivans (29%) during 2004–2005 was significantly higher than expected (7%). We discuss several competing hypotheses about why bears selected minivans.
Basically, the authors looked at the National Park Service database of bear vehicle break-ins in Yosemite Valley from 2001 to 2007 and broke down the data by the bruins' choice of vehicle type for each nocturnal breaking-and-entering session. Even though minivans represented only 7% of the vehicles parked overnight in Yosemite Valley, an astounding 28% of all ursine vehicular incursions were directed against minivans.

Read the article for yourself (not sure how long this link will persist.)

Why do bears love minivans so much? Is it the comfortable bucket seats, the generous cargo area, the convenient sliding doors, the "not great but really pretty ok for a big car" gas mileage? It is well known that bears enjoy all things automotive: outside Denver, a bear broke into a car, put it in gear, and crashed it into a tree. The car was a total loss. Back to minivans, though, it turns out that the convenient sliding doors and adjustable seats are part of the allure. One of the authors was quoted in a San Francisco Chronicle article on the study as saying that bears pry open the doors, tear out back seats, and pop open windows (rear side windows are apparently their favorite entry route) in their quest for people food stashed in minivans. Do the bruins favor vehicles with Stow-N-Go seating for easy removal of back seats? The results are unclear, but my thought experiments strongly indicates the answer may be yes.

In the end, the answer comes down to children. Not that the children are themselves food for the bears (really, only witches regularly consume children, though the occasional ghoul will take a child in opportunistic feeding situations), but insofar as minivans are likely to be used to transport children, who grind Goldfish dust soaked with Capri Sun into the upholstery. No matter how fastidious the grown-ups are about not leaving food in the van, the atomized food particles in the seats are sufficiently odorous to compel a passing bear to break and enter in hopes of scoring a pawful of Cheerios and a Sunny D chaser.

Sounds like folks across the Pacific are no better off. According to several reports, bear attacks are on the rise in Japan. Are Japanese bears smaller and more efficient maulers? That's unclear, but the Land of the Rising Sun has a storied history of bear attacks. The man-eater was probably just frustrated because minivans wouldn't be invented for another 70 years or so.


Stewart W. Breck, Nathan Lance, and Victoria Seher. (2009). "Selective foraging for anthropogenic resources by black bears: Minivans in Yosemite National Park". Journal of Mammalogy 90(5):1041–1044.

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