Flowcharts for Identifying Gulls (black and white might be better on your monitor)
 
 
 
Part 1. Adult Gulls (black and white)
Part 2. All Brown or Mottled Brown Gulls (black and white)
Part 3. Gulls with Gray Backs and Brown Wings (black and white)
Part 4. Like an Adult Gull but ... (black and white)

Flowcharts copyright 1980 by Joseph Morlan. Reprinted by permission. Developed for birding classes at San Francisco City College. See http://fog.ccsf.cc.ca.us/~jmorlan/ for course schedules and further information.

General Notes on the Occurrence of Gulls in the Monterey Bay Region by David Suddjian