Set in a fictional Texas wildlife Refuge along the Rio Grande, birdwatchers from across the country converge to look for birds to add to their life lists. A graduate student from Boston, a physician, and a detective who hates birds, come together to investigate the murder of a bird watcher who was a friend of the doctor, and boyfriend of the young grad student. Interesting, multiple plots lines, plenty of red herrings. Published in 1982 it has a bit of a retro feel from the days before cell phones.