Iceland Gull in third basic (winter) plumage at Ashbridges Bay on 23
February 2008.Kumlien's Iceland Gull in third (winter) basic
plumage. Third year birds are the rarest age class in the
population. Later this year in the fall this individual will become
an adult. Adults and first year birds are the two commonest age
class in the population, followed by second year birds, and finally
third year birds such as this individual, which are the least common
age class as mortality accumulates before adult plumage is reached.