The source of mysteries is not limited to the likes of Tony Hillerman or P.D. James. Nature also serves up some perplexing whodunits from time to time. On the evening of January 25th, 1983 several people called the Lacassine National Wildlife Refuge in southwest Louisiana where I worked to report unusual snow goose mortality near Jennings. As the regional wildlife disease biologist, I was responsible for looking into the matter.