Typical tail pattern
Example of an unusually dark tail
Example of an unusually dark tail (same bird as n° 21)
colour-ringed blue CY*AZ -- 1st-cycle Herring Gull, ringed at Zeebrugge, Belgium
colour-ringed blue CU.AK -- 1st-cycle Herring Gull, ringed at Zeebrugge, Belgium
colour-ringed blue M.CAP --
