Except where stated otherwise, all of these pictures of Kelp Gull Larus dominicus were taken by me in Chile.
The stated ageing is tentative - I would like to receive informed comment:-

: a juvenile (standing); from Antarctica in Jan.
: a juvenile (standing); from southern Chile in Feb.
: two fresh first-basics (flying) from Tierra del Fuego in Feb.
: a presumed first-basic (standing; flying) from the upper Texas coast - added 12/19/08 .
: three first-alternates (standing) from Tierra del Fuego in Nov.
: a presumed first-alternate (standing) from Tierra del Fuego in Feb.
: a presumed first-alternate/2nd basic (standing); from southern Chile in Feb.
: presumed first-basics and 2nd-basics (standing); from central Chile in Feb.
: a presumed 2nd-basic Kelp or Kelp hybrid ( standing, flying); from NE Mexico in Sep. - added 6/15/00
: a molting adult (flying); from southern Chile in Feb.
: a molting adult (standing); from southern Chile in Feb.
: a worn alternate adult (standing); from central Chile in Feb.
: a 4th-Basic? (standing); the bird at Galveston, Texas in March
: three adult-alternates (standing, flying); from Antarctica in Jan.
: a third-alternate (standing + open wing); from southern Chile in Nov.
: a third-alternate (standing); from central Chile in Feb.
: an apparent adult hybrid (standing); from Texas in March
: a molting adult (standing, flying) from N.E. Mexico in Sept.
: 3 possible imm. hybrids (standing, flying) from N.E. Mexico in Sept.