Gulls as a group can be difficult to correctly identify. Depending on the species, they can take two to four years to reach their adult plumage. To add to the challenge, they can molt several times a year giving them even more variety to their looks. There are 12 subject species in this group. Images include Bonaparte’s, California, Franklin’s, Glaucous-winged, Heerman’s, Herring, Laughing, Mew, Ring-billed, Western and Yellow-footed Gulls, and Long-tailed Jaeger (or Skua).