Kevin Karlson has recently posted the following on ID Frontiers:
Pete Dunne and I are just wrapping up a new book for Princeton Univ Press called Gulls Simplified, where we hope to share a vast visual collection of gull photos that are presented in order of age, with many digital collages of six views for a species in a singular calendar year so that birders who never try to identify gulls might have a chance with a book that shows most of the possibilities of each species as juvenile/immatures, sub-adults and adults at various times of the year.