Common Tern

White ring with a black three alpha-numeric code, starting letter 'S' followed by two numbers (on right tarsus) and metal ring (on left tarsus).  

note 1 : note 1 : this project starts running in Sečovlje Salina Nature Park & Škocjanski zatok Nature Reserve (Slovenia) from april 2014.

Orange ring with a black three alpha-numeric code (on right leg) and metal ring (on left leg).

note 1 : used codes : letter-number-number since 2013 (A, F, G, H, J, K, L, M, N, P, T, U, V, W, Y.

note 2 : used codes : letter-letter-number since 2018.

note 3 : used codes : letter "A"-letter-number ; letter-number-number ; letter "C"-letter-number.

note 4 : used codes are : Ann ; Cnn ; Fnn ; Gnn ; Hnn ; Jnn ; Knn ; Lnn ; Mnn ; Nnn ; Pnn ; Tnn ; Unn ; Vnn ; Wnn ; Y01-Y80.

note 5 :

Yellow ring with a three alpha code, starting letter "T".

note 1 : used codes are TAA-TZZ.

note 2 : 

Yellow ring with a black three alpha code.

note 1 : used codes are FAA-FZZ.

note 2 : this project had run on two places in Northeast Germany from 2012 to 2016.

note 3 :

Black ring with a white 3 alpha-numeric code (starting letter 'I') (on left tibia).

note 1 :

Combination of :
* dark-green ring with a white 2 numeric code (on left leg).
* red ring above metal ring (on right leg).

note 1 : used codes are 00 till 99, excluding doubles e.g. 69 & 96, 86 & 98.

note 2 : from 2015 onwards a red ring above the metal ring (on right leg) will be added.

note 3 : this is used in order to distinguish from an illegal Spanish project.

note 4 : birds ringed in Warwickshire, UK.

note 5 : 

Yellow ring with a black three alpha-numeric code, starting letter 'F' followed by two numbers (on one leg) and metal ring (on the other leg).   

note 1 : Common Terns are ringed as nestlings on a large breeding platform at Lake Starnberg, Bavaria, Germany.

note 2 : 

2 rings (without code) on right tarsus (usually on right, occasionally on left) and aluminium ring on left tarsus (usually on left, occasionally on right) (adults/juveniles).

note 1: before 1995 : only aluminum rings with code on left tarsus.

note 2: 1995 : light-green and white (both at the top as well as at the bottom) and green-yellow.

note 3: 1996 : no colourrings, only aluminium rings with code on left tarsus.

note 4 : 1997 : green at the top and yellow at the bottom (exceptional opposite).

note 5 : 1999 : some 600 juv. birds have been marked with a ring (green at the top and yellow at the bottom).

note 6: in 2000 only ad. birds have been marked with colourrings.

c-ring (without code) on one leg.

note 1 :

Combin ation of c-rings : 1 c-ring (on right tarsus) and 2 c-rings (on left tarsus).