"Pepperberg. Sadly, Alex passed away on September 6, 2007 at the age of 31 of a sudden, unexpected catastrophic event associated with arteriosclerosis (hardening of the arteries). It was either a fatal arrhythmia, heart attack, or stroke, which caused him to die suddenly with no suffering. "
Unfortunately, Alex was given many treats - peanuts, walnuts and various other fatty/sugary things to facilitate his training and to assuage his overpowering personality consistently over a period of 30 years. Alex had also had a severe case of aspergillosis which damaged his breathing.