It appears that Metro's Oregon Zoo has embarked upon a strategy to drive all experienced staff out of the organization: anybody older than around 45 is apparently considered a liability. The most recent victim is an older individual widely regarded as the most experienced caretaker of primates in North America.
Specializing in chimpanzee management, the keeper has been held in high regard by people like Jane Goodall, yet the Metro Oregon Zoo has dismissed him, due to an apparent accident. Information available indicates that someone left a door unsecured, and when the keeper let the animals into the area, they were able to enter a secure hallway. Although no animals or people suffered injury, Metro Oregon Zoo has determined that the incident is grounds for dismissal.
By contrast, a much younger keeper reportedly comitted an error that resulted in the death of a number of birds; she recieved no disciplinary action.
Metro Oregon Zoo continues to build a case for a class-action lawsuit on the basis of age discrimination.