By Kim Smiley

On December 25, 2007, a tiger escaped her enclosure at the San Francisco Zoo and attacked three people.  One 17 year old boy was killed and the other two were injured. The enclosure was built in the 1940s and had safely contained tigers for more than 60 years without incident.

So how did this happen?  How did the tiger escape?

A Cause Map can be built using this example to help determine how this incident was able to occur. To begin a Cause Map, the impacts to the organizational goals are first determined and then “why” questions are asked to add causes to the map.  In this case, there was obviously an impact to the safety goal because one zoo patron was killed and two were injured.  The customer service goal was also impacted because the zoo was closed until January 3, 2008 following the incident.  Why was a zoo patron killed?  He was killed because he was mauled by a tiger.  Why was he mauled?  Because the tiger escaped her enclosure and she went after the victims.

Let’s focus on the question of how the tiger escaped her enclosure first.  An investigation was conducted by the United States Department of Agriculture’s Animal and Plant Health Inspection Service, the government body who is charged with overseeing the nation’s zoos.  Based on claw marks and other evidence at the scene, they determined that the tiger jumped from the bottom of a dry moat and was able to pull herself over the fence surrounding her enclosure.  The investigation also determined the fence was lower than typically used around tiger enclosures.  The Association of Zoos & Aquariums recommends that walls around a tiger exhibit be at least 16.4 feet and the fence around the San Francisco Zoo was only 12.5 feet at the time.

The second question of why the tiger went after the boys is not as easy to answer.  A few experts have stated that the tiger didn’t behave in a typical way.  There has been significant speculation in the media that the victims taunted the tiger or provoked her in some way, but nothing has ever officially been determined.

This focus on the behavior of the victims is a good example of some of the issues that can come up during an investigation.  It can be tempting to focus on assigning blame when investigating an incident.  But the real question is “What should we do to prevent this from happening again?”.  Whether or not the boys provoked the tiger, she should never have been able to escape her enclosure.

After the incident, the zoo extensively remodeled the tiger enclosure, adding a much higher fence and with hotwire at the top to prevent any similar incidents from occurring.