I haven't read the ones Ian was mentioning, but I have read all four of Christine Goff's bird watcher's murder mysteries. They all take place in the Estes Park and surrounding areas. There is an environmental or conservation theme and involve a body being discovered by birders. The author is a knowledgeable birder and attended the ABA Conference in Fort Collins a few years ago. She went on some of the field trips and one of her books covers some of the field trips, altho they areas are disguised by other names, e.g., Estes Park is Elk Park in the books and the big white mansion and hotel to the north of town is the meeting place for a lot of activities. It is the hotel that was featured in the Jack Nicholson's movie "The Shining".

Google "Christine Goff" to get comments on her books.

Hugh Jennings
Bellevue, WA
hughbirder at earthlink.net